WO1999028755A2 - Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users - Google Patents

Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users Download PDF

Info

Publication number
WO1999028755A2
WO1999028755A2 PCT/IT1998/000330 IT9800330W WO9928755A2 WO 1999028755 A2 WO1999028755 A2 WO 1999028755A2 IT 9800330 W IT9800330 W IT 9800330W WO 9928755 A2 WO9928755 A2 WO 9928755A2
Authority
WO
WIPO (PCT)
Prior art keywords
earthing
circuit
electrical
electronic circuits
test
Prior art date
Application number
PCT/IT1998/000330
Other languages
French (fr)
Italian (it)
Other versions
WO1999028755A9 (en
WO1999028755A3 (en
Inventor
Michela Cali'
Serafino Schillaci
Original Assignee
Cali Michela
Serafino Schillaci
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from ITPA970023 external-priority patent/IT1297454B1/en
Priority claimed from ITPA980002 external-priority patent/IT1306323B1/en
Application filed by Cali Michela, Serafino Schillaci filed Critical Cali Michela
Priority to AU22467/99A priority Critical patent/AU2246799A/en
Publication of WO1999028755A2 publication Critical patent/WO1999028755A2/en
Publication of WO1999028755A3 publication Critical patent/WO1999028755A3/en
Publication of WO1999028755A9 publication Critical patent/WO1999028755A9/en

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
    • G01R19/145—Indicating the presence of current or voltage
    • G01R19/155—Indicating the presence of voltage
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/66—Testing of connections, e.g. of plugs or non-disconnectable joints
    • G01R31/68—Testing of releasable connections, e.g. of terminals mounted on a printed circuit board
    • G01R31/69—Testing of releasable connections, e.g. of terminals mounted on a printed circuit board of terminals at the end of a cable or a wire harness; of plugs; of sockets, e.g. wall sockets or power sockets in appliances
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/52—Testing for short-circuits, leakage current or ground faults
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/54—Testing for continuity

Definitions

  • Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users.
  • the invention consists of some electronic circuits connected to phase, neutral and earth of the electrical users assembled on tools, plugs or accessories, allowing to detect the earthing of the electrical installations and the test of the residual current circuit-breakers efficiency, and regards the technical field of the electrical safety in household and industrial environment, and the test of the earthing in the electrical systems type EE (Earth-Earth) and EN (Earth-Neutral).
  • EE Earth-Earth
  • EN Earth-Neutral
  • the industrial invention consists of some electronic circuits of a very low cost; each circuit can be connected to phase, neutral and earthing of an electrical user, or assembled on a tool, plug, socket, or on an accessory installed in a household appliance.
  • the electronic circuits reveal the earthing connection for example of an electrical socket in an electrical installation or of the metallic carcass in a household appliance, by turning on light signals.
  • Some tools have the features of a plug and work by being inserted into a socket of the electrical installation in systems EE and EN with a network tension of 230V between phase and neutral, in ac 50/60 Hz and do not cause the activation of protection residual current circuit-breakers .
  • Other tools serve for testing the efficiency of residual current circuit-breakers, with fixed test residual current and break time.
  • the electronic circuits can also be inserted in parallel into a household appliance, or electrical user, etc., by being connected to the phase, the neutral and the metallic carcass of the electrical user (as described below), in this way it is obtained an electrical safety accessory of the user, the earthing/test accessory, which detects the connection of the same user metallic carcass to the earthing of the electrical installation, to which the accessory is connected through its own socket with cable and plug of type 2P+E (2P+Earth).
  • the electronic circuits can also be installed in a domestic or industrial electrical panel-box, or they can replace a switch or a socket; in each case they will be able to signal the presence or the absence of the domestic or industrial electrical installation earthing connection, therefore they will signal an eventual local or general breakdown occurred to the earthing system in a house, industry or office.
  • the electronic circuits of this invention can be employed in many electrical installation in different countries, by varying properly some electrical components of the circuits, such as the resistance values, the features of the signallers or the commercial leds. Brief description of the drawings
  • FIG. 1 shows the electronic circuits proposed by this invention, and in particular those relative to the electrical schemes 101, 102, 103, 104, 105, 106, 107, 108 and 109, represented respectively by figures 1, 2, 3, 4 and 5, 11, 14, 16 and 17 and in the specific tecniques by figures 6, 7, 8, 9, 10, 12, 13, 15, and 18.
  • All the schemes showing the electronic circuits 101-109 are represented inside a dotted line poligon; the features of the electrical components, the resistance and capacity values, the kind of diods, leds and transistors are into the poligon as well; external to the poligon there are some numbers indicating the reference to explain the content of the invention.
  • the dotted line poligons can be compared to some glass plates containing the components of the circuits.
  • the electronic circuits work by shutting (or not) the breakdown ring between the consumer's earthing and the earthing of the electrical transformer cabin (as shown in figure 39, electronic circuit of scheme 102, connected to phase (L3) in terminal point 12, to neutral (N) in terminal point 13 and to earthing (PE) in terminal point 14).
  • the electronic circuits and their connection to the electrical users like a socket, through phase, neutral and earth, allow the circulation of the current into a branch of the circuit that activates the green led. This happens by shutting the breakdown ring, through the consumer's and the cabin earthing.
  • Figures 1 and 6 show the electronic circuit, electrical scheme 101, composed of resistances 1 and 2 of variable values, for instance between 330 and 68 K ⁇ , and of light signal or led 3; the terminal points 4, 5 and 6 of the electronic circuit must be connected to the phase, neutral and earth respectively in order to work.
  • the light signaller 3 has the following features, indicative but not absolute: conical signaller or neon hollow with an incorporated or not resistance, supplying of 230 V, triggering tension 50 V, coulored light, or alternatively the features of a common commercial led diode.
  • the light signaller or green led diode 3 will be activated when it finds the presence of a network tension with another means, if the monophase electrical installation 230V between phase and neutral, provided with protection conductor connected to the circuit of scheme 101, is also connected to an earthing.
  • Figures 2 and 7 shown the components of the electronic circuit, scheme 102, which are attributed indicative, but not absolute, values mentioned below: - a 68 K ⁇ resistance 7, a 68 K ⁇ resistance 8, a 68 K ⁇ resistance 9, a green led diode signaller 10, a yellow led diode signaller 11.
  • the terminal points 12, 13 and 14 of the electronic circuit, (scheme 102), must be connected to the phase, neutral (of electrical supply) and earth respectively, in order to work.
  • the light signaller or green led 10 will be activated when it finds the presence of a network tension by the yellow led 11 activation, if the electrical installation 230V between phase and neutral (provided with protection conductor) connected to the circuit of scheme 102, is also connected to an earthing.
  • FIGS. 3 and 8 show the components of the electronic circuit, scheme 103, which are attributed indicative, but not absolute, values mentioned below:
  • FIGS. 4 and 9 show the components of the electronic circuit, scheme 104, which are attributed indicative, but not absolute, values mentioned below:
  • the terminal points 41, 42 and 43 of the electronic circuit must be connected to the phase, neutral and earth respectively, in order to work.
  • the light signaller or green led 34 will be activated when it f ⁇ ds the network tension, by the yellow led 33 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor, connected to the circuit of scheme
  • FIG. 5 and 10 show the components of the electronic circuit, scheme 105, which are attributed indicative, but not absolute, values mentioned below: a 56 K ⁇ resistance 47, a bridge of diodes 48 type 1N4148 X 4, a 4.7 K ⁇ resistance 55, a 68 K ⁇ resistance 50, a green led diode 51, a 1 K ⁇ resistance 52, an optoinsolator 53 of type SFH-611-3, a transistor 54 type BC237, a 4.7 K ⁇ resistance 55, a 12 K ⁇ resistance 56, a 47 KpF capacitor 57, a 47 KpF capacitor 58, a 12 K ⁇ resistance 59, a 4.7 K ⁇ resistance 60, a transistor 61 type BC237, an alarm piezoelectric buzzer 62, a 47 microfarad -50V capacitor 63, a yellow led diode 64, a 1 K ⁇ resistance 65, a
  • the terminal points 44, 45 and 46 of the electronic circuit must be connected to the phase, the neutral and the earth respectively, in order to work.
  • the light signaller or green led 51 will be activated when it finds the presence of a network tension by the yellow led 64 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor, connected to the circuit of scheme 105, is also connected to an earthing; in case of no connection to the earthing the alarm piezoelectric buzzer 62 will turn on.
  • Figures 11 and 12 show the components of the electronic circuit, scheme 106, which are attributed indicative, but not absolute, values mentioned below: a 56 K ⁇ resistance 69, a 56 K ⁇ resistance 73, a bridge of diodes 74 type 1N4148 x 4, a 68 K ⁇ resistance 75, a 68 K ⁇ resistance 76, a green led 77, a 1 K ⁇ resistance 78, an optoinsolator 79 of type SFH-611-3, a transistor 80 type BC237, a 4.7 K ⁇ resistance 81, a 12 K ⁇ resistance 82, a 47 KpF capacitor 83, a 47 KpF capacitor 84, a 12 k ⁇ resistance 85, a 4.7 K ⁇ resistance 86, a transistor 87 type BC237, a buzzer 88, a 1 K ⁇ resistance 89, a red led diode 90, a 47 microfarad -50V capacitor 91, a yellow led diode 92, a 1 K ⁇ resistance 93,
  • the green led 77 will be activated when it finds the power tension by the yellow led 92 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor connected to the circuit of scheme 106, is also connected to an earthing; in case of no connection to the earthing the sonoric alarm 88 and the red led 90 will turn on.
  • Figures 13 and 14 show the components of the electronic circuit, scheme 107, which are attributed indicative values mentioned below: a 68 K ⁇ resistance 99, a 1 K ⁇ resistance 100, a photoinsulator 110 of type SFH 611-33, a red led diode
  • the light signaller or green led 115 will be activated when it finds the presence of the network tension by the yellow led 112 activation, if the electrical installation 230 V between phase and neutral, provided with protection conductor, connected to the circuit of scheme 107, is also connected to an earthing; in case of no connection to the earthing the common commercial red led 111 will turn on.
  • Figures 15 and 16 show the components of the electronic circuit, scheme 108, which are attributed indicative values mentioned below: a switch composed by a shunter 121, a 6.8 K ⁇ resistance 122, a 68 K ⁇ resistance 123, a 1 K ⁇ resistance 124, a green led commercial diode 125, a photoinsulator 126 type SFH-611-3, a red led diode 127, a yellow led commercial diode 128, a diode 129 type 1N4148, a 68 K ⁇ resistance 130, a 68 K ⁇ resistance 131, a bridge of diodes 132 type 1N4148 x 4, a 6.8 K ⁇ resistance 133, a 4.7 K ⁇ resistance 160.
  • a switch composed by a shunter 121, a 6.8 K ⁇ resistance 122, a 68 K ⁇ resistance 123, a 1 K ⁇ resistance 124, a green led commercial diode 125, a photoinsulator 126 type SFH-611-3, a red led
  • the terminal points 118, 119 and 120 of the electronic circuit must be connected to the phase, neutral and earth respectively, in order to work.
  • the light signaller or green diode led 125 will be activated when it finds the network tension by the yellow led 128 activation, if the electrical installation 230 V between phase and neutral, provided with protection conductor, connected to the circuit of scheme 108, is also connected to an earthing. In case of no connection to the earthing the the red led 127 will turn on.
  • a 6.8 K ⁇ resistance 137 a phototriac 138 type MOC 3020, a phototriac 139 type MOC 3020, a 6.8 K ⁇ resistance 140, a 2.2 K ⁇ resistance 141, a transistor 142 type BC558, a 2.2 K ⁇ resistance 143, a 47 K ⁇ resistance 144, a 100 K ⁇ resistance 145, a 100 K ⁇ resistance 146, a 68 K ⁇ resistance 147, a green led commercial diode 148, a 68 K ⁇ resistance 149, a 4.7 microfarads capacitor 150, a bridge of diodes 151 type 1N4148 X 4, a 1.5 K ⁇ resistance 152, a yellow led commercial diode 153, a test push button 154, a 0.2 microfarad capacitor 155, a transistor 156 type BC238, a transistor 157 type BC238, a 56 K ⁇ resistance 158, a 1 K ⁇ resistance 159.
  • 104 and 105 can be installed or assembed on a tool that has the feature of a plug without a cable, type
  • Figures 19 and 20 show the find/earth tool 167 and the relative electronic circuit (figures 1 and 6 - scheme 101), composed of resistances of variable value 1 and 2 i for example between 330 and 68 K ⁇ , connected to the pins of phase 164 in terminal point 4 through conductor 161, and of neutral 165 in terminal point 5 through conductor 163, and of the light signaller or green led diode 3 connected to the pin of earthing 166 in terminal point 6 through conductor 162.
  • the green led diode 3 (figure 20) will turn on if the socket connected to the find/earth revealer tool 167 is also connected to an earthing; if there is no connection to the earthing the green led 3 will not be activated.
  • the electronic circuit described is simmetrical and so the phase and the neutral can be inverted, this allows the insertion of tool 167 (that has the features of a plug without a cable as shown in figures 19 and 20) into the socket in question in any way.
  • the find/earth tool 167 of figure 19 and 20 will be activated when it finds the presence of a network tension on the socket in question with another means (tool or indicating instrument).
  • the find/earth tool 167 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a current higher than 10 mA, as the resistances 2 and 1 have values between 330 and 68 K ⁇ , for instance .
  • FIGS 21 and 22 are shown the find/earth tool 171 and the relative electronic circuit (figures 2 and 7 - scheme 102), connected to the pins of the phase in terminal point 12 through conductor 168, of the neutral in terminal point 13 through conductor 169, and of the earth in terminal point 14 through conductor 170.
  • the green led diode 10 (figure 22) will turn on if the socket connected to the find/earth revealer tool 171 is also connected to an earthing; if there is no connection to the earthing the green led 10 will not be activated.
  • the electronic circuit of scheme 102 is electro-simmetrical and so the phase and the neutral can be inverted, this allows the insertion of the tool into the socket in question in any way.
  • the tool 171 reveals the power tension of a socket through the yellow led diode 11, and it is made in a way that does not involve the residual current circuit breakers installed upstream the sockets with a residual current higher than 10 mA.
  • Find/earth tool 172 is shown in figure 23 while the electronic circuit is in figures 3 and 8 (scheme 103); it is connected to the phase pin of tool 172 (plug 2P+E without a cable) in terminal point 25, to the neutral pin in terminal point
  • the flashing green led diode 22 (figures 3, 8, 23) will turn on if the socket connected to the find/earth revealer tool 172 is also connected to an earthing; if there is no connection to the earthing the green led 22 will not be activated.
  • the electronic circuit of scheme 103 is electro-simmetrical and so the phase and the neutral can be inverted, this allows the insertion of tool 172 into the socket in question in any way.
  • the tool 172 reveals the line's network tension of a socket through the yellow led diode 21.
  • the find/earth revealer tool 172 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a residual current higher than 10 mA.
  • Find/earth tool 173 is shown in figure 24 while the electronic circuit is in figures 4 and 9 (scheme 104); it is connected to the phase pin of tool 173 in terminal point
  • the electronic circuit (scheme 104) is made of electric and electronic components activating different coulored leds with fixed or flashing light and namely: fixed light yellow led 33 for eventual tension in the socket; fixed light green led 34 for the earthing connection; or alternatively - flashing light red led 35 for no earthing connection.
  • the electronic circuit of scheme 104 is electro-simmetrical, this allows the insertion of tool 173 into the socket in question in any way.
  • Find/earth tool 173 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a residual current higher than 10 mA.
  • Find/earth tool 174 is shown in figure 25 while the electronic circuit is in figures 5 and 10 (scheme 105); it is connected to the phase pin of tool 174 in terminal point 44, to the neutral pin in terminal point 45 and to earth pin in terminal point 46.
  • the (electro-simmetrical) electric circuit (scheme 105) is made of electric and electronic components that can activate different coulored leds with fixed light or a sonoric alarm, and namely: fixed light yellow led 64 for eventual tension in the socket; fixed light green led 51 for the earthing connection; or alternatively sonoric piezoelectric buzzer 62 for no earthing connection.
  • Find/earth tool 174 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a residual current higher than 10 mA.
  • Figures 28 and 29 show (in ratio of about 1:1, and in a longitudinal section and externally) the electrical safety and RCBB/test and earthing/test tool 177 that uses the electronic circuit of scheme 108 of figures 15 and 16, and allows to make a verification on sockets protected by residual current circuit-breakers with a current of 30 mA.
  • the RCBB/test and earthing/test tool 177 detects: - the network tension by yellow led diode 128; the presence or the absence of connection the socket in which it inserted, to the general earthing of the electrical installation in question, by green led diode 125 or alternatively red led diode 127; the efficiency of the RCBB used as a protection of the socket with a test current of about 30 mA, through a test switch 121 composed by a shunter.
  • the tool 177 is obtained by connecting terminal point 118 of the electronic circuit (scheme 108) to the phase pin (of plug type 2P+E) by conductor 180, terminal point 119 to the neutral pin by conductor 178 and terminal point 120 to the earth pin by conductor 179, as shown in figure 28.
  • Figures 30 and 31 show the tool 181 composed of the electric circuit of scheme 109 (figures 17 and 18), which gives the signal of tension through yellow led 153 and the signal of earthing connection through green led 148, it can also cause the intervention of the residual current circuit- breakers through test push button 154, if the current is higher than 30 mA for 20 ms.
  • circuits represented in schemes 101, 102, 103, 104, 105, moreover 106 and 107 of figures 1, 2, 3, 4, 5, moreover 11 and 14 can work in parallel, they can be inserted into any plug with cable type 2P+E (as shown in figure 32, scheme 107) in this way it is obtained a plug provided with earthing/test served and connected to a tool or an household appliance.
  • a plug with cable type 2P+E
  • the electronic circuit of scheme 107 can be inserted (as shown in figure 32) into any plug 182 with 2P+E cable 190, obtaining a plug with earthing/test 182 connected to a household appliance or user 183 (figure 33), this detects only whether the earthing of the socket, in which plug 182 (disclosed in figure 34 separated from the household appliance or user which is served) of the household appliance 183 is inserted, is connected to the general earthing system, as shown in figure 32 (scheme 107).
  • the earthing/test plug displays the features of the circuit installed.
  • circuits represented in schemes 101, 102, 103, 104, 105, moreover 106 and 107 of figures 1, 2, 3, 4, 5, moreover 11 and 14 can be inserted into any plug with cable type 2P+E by connecting their terminal points to any point of the phase, neutral and earth conductors, (as it has been shown previously), obtaining cables and extensions with plug and socket provided with a permanent control of the earthing; that is an earthing/test. Therefore cables and extensions will be provided with a permanent control of the earthing that is the earthing/test displaying the features of the circuit installed, and in particular of its own light signallers.
  • circuits represented in schemes 101, 102, 103, 104, 105, 106 and 107 of figures 1, 2, 3, 4, 5, 11 and 14 can work in parallel, they can be inserted into any plug with cable type 2P+E of an appliance, of a tool or of an electrical user (as shown in figure 35, scheme 104) obtaining a plug provided with cable type 2P+E+earthing/test conductor/signaller.
  • the electrical connection of the appliance to the metallic carcass is obtained by passing a signaller/conductor through the supplying cable (type 2P+E) of the appliance, with the phase, neutral and earth wires, and this is coincident with the connection point of the earthing conductor of the same supplying cable (as shown in figure 35 electronic circuit of scheme 104).
  • the plug 193 In order to supply the household appliance the plug 193 must be inserted into socket 201 with a tension of 230 V between phase (P) and neutral (N), and provided with the earthing (E).
  • the red led diode 35, the yellow led diode 33 and the green led diode 34 will be placed on plug 193 (shown not connected to appliance in figure 36) each with the bulb placed on the external part of the plug.
  • the plug 193 with 2P+E cable 194 + earthing/test conductor/signaller 195 (cable 194 shown in figure 35 without the protecion envelope) is made of electric and electronic components able to activate different coulored leds with fixed or flashing light; they are: fixed light yellow led 33 for eventual network tension in the household appliance 200; fixed light green led 34 for the general earthing electrical installation connection of the metallic carcass 199 of the household appliance 200; or alternatively flashing light red led 35 for no general earthing electrical installation connection of the metallic carcass 199 of the household appliance 200.
  • the plug with cable 2P+E+earthing/test conductor/ signaller connected to the appliance will have the features of the circuit installed, and in particular of their own signallers.
  • Another way to make the invention is to place the electronic circuits of the invention on an accessory (for example composed of a plastic plaque) assembled on the appliances, on the tools or on the electrical users which connection between the electronic circuits and the metallic carcass is directly made in any point of the metallic mass of the household appliance.
  • an accessory for example composed of a plastic plaque
  • Figure 37 shows in ratio 2:1 the accessory 202 composed of a plastic plaque or resin (or another material electrically isolated from present metallic mass) with a rectangular shape which size is about 5x3x0.5 cm, and that can be attached, applied or screwed on the household appliances or electrical users through supports 203 and 204; this has the earthing test switch 205 (for example of type normally closed or open, double stable etc..) and the light led diodes.
  • the leds are: the (green led) 34 for the presence of an earthing, the (red led) 35 for its absence and the (yellow led) signaller 33 for the network tension, relating to electronic circuit of scheme 104 of the figures 4 and 9.
  • connection of the circuit of the scheme 104 (figures 4 and 9) of the accessory 202 to the phase, to the neutral and to the metallic carcass of the appliance (or electrical user or tool) is shown in figure 38, and it is obtained electrically by connecting respectively: terminal point 41 to point 207 of the phase conductor of the appliance 206; terminal point 42 to point 208 of the neutral conductor of the appliance 206; terminal point 43 to any point 209 of the metallic carcass of the household appliance 206; this way it is obtained the safety earthig/test accessory 202, installed in the appliance 206, and that detects the connection of the same user 206 metallic carcass to the general earthing of the electrical installation, to which is connected by the cable 209 (shown in figure 38 without the envelope) and the plug 210 of type 2P+E provided with earth 211 connecting user 206 by a cable inserted into socket 212 (represented as a rectangle containing th letters P N E ), connected to the network tension.
  • the safety earthing/test accessory 202 has the electrotecnique features of its own electronic circuit, scheme 104 of the figures 4 and 9.
  • figure 38 it is shown the place 213 of the accessory 202 on the household appliance 206 where it will be fixed through supports 203 and 204, while figure 37 show the leds or light signaller 33, 34 and 35 protruding externally with their bulbs on the external part of accessory 202.
  • the safety earthing/test accessory assembled on the appliance will have the features of the circuit installed, and in particular of their own signallers.
  • the industrial applicability of this invention depends on the fact that it makes possible a fast verification of the earthing particularly in a household, but also in an industrial environment, with a very low cost and by simple electronic circuits; this verification can, in fact, be carried out, with a simple tool by people not qualified in the scientific field of the electrical safety.
  • this invention introduces (and this is a new proposal) the possibility to install the safety earthing/test accessory provided with permanent or by test electronic control of the earthing on the household appliances.
  • the earthing/test accessory gives, in fact, the maximum safety for the use of the appliance in which it is installed.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Details Of Connecting Devices For Male And Female Coupling (AREA)
  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)

Abstract

The object of this invention are some electronic circuits represented on schemes (101, 102, 103, 104, 105, 106, 107) reported on the description; they are useful for the detection of the earthing system and the test of the residual current circuit-breakers efficiency, and they are connected to the phase, the neutral and the earth of the electrical users (such as an electrical installation, a socket, a tool or an appliance). The electronic circuits are installed on tools (167, 171, 172, 173, 174, 175, 176), some of which (177, 181) can make intervene the residual current circuit-breakers assembled for protection on the appliances, plugs served to appliances (182), cables and extensions provided with plug and socket, plugs (193) provided with cables type 2P + E +earthing/test conductor/signaller (194), or they are installed in an accessory (202) assembled on the electrical user, and work by turning on a green or other coloured light led.

Description

Description
Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users.
Technical field
The invention consists of some electronic circuits connected to phase, neutral and earth of the electrical users assembled on tools, plugs or accessories, allowing to detect the earthing of the electrical installations and the test of the residual current circuit-breakers efficiency, and regards the technical field of the electrical safety in household and industrial environment, and the test of the earthing in the electrical systems type EE (Earth-Earth) and EN (Earth-Neutral).
Background art
In order to guarantee the electrical safety and the test of the earthing in EE and EN electrical systems in the industrial environment, it is necessary the use of expensive and complex devices, and in the household environment the use of devices to be inserted into the sockets and that can involve a non selective residual current circuit-breakers activation.
There is no safety earthing/test accessory already installed on the electrical appliances (or industrial electrical users) on sale, provided with electronic circuits for a permanent or by test electronic control (with switches) of the earthing systems; this is what this invention proposes.
Disclosure of invention
The industrial invention consists of some electronic circuits of a very low cost; each circuit can be connected to phase, neutral and earthing of an electrical user, or assembled on a tool, plug, socket, or on an accessory installed in a household appliance.
The electronic circuits reveal the earthing connection for example of an electrical socket in an electrical installation or of the metallic carcass in a household appliance, by turning on light signals. Some tools have the features of a plug and work by being inserted into a socket of the electrical installation in systems EE and EN with a network tension of 230V between phase and neutral, in ac 50/60 Hz and do not cause the activation of protection residual current circuit-breakers . Other tools serve for testing the efficiency of residual current circuit-breakers, with fixed test residual current and break time.
Moreover, it is possible to obtain a test plug with earthing signal (and network tension) by inserting in parallel one of the electrical circuits into the plug of an electrical user (household appliance or other tools), otherwise the electrical circuits can be installed in any point of a cable and extension with plug and socket which, thus, will result provided with a permanent control of the earthing. The electronic circuits can also be inserted in parallel into a household appliance, or electrical user, etc., by being connected to the phase, the neutral and the metallic carcass of the electrical user (as described below), in this way it is obtained an electrical safety accessory of the user, the earthing/test accessory, which detects the connection of the same user metallic carcass to the earthing of the electrical installation, to which the accessory is connected through its own socket with cable and plug of type 2P+E (2P+Earth).
The electronic circuits can also be installed in a domestic or industrial electrical panel-box, or they can replace a switch or a socket; in each case they will be able to signal the presence or the absence of the domestic or industrial electrical installation earthing connection, therefore they will signal an eventual local or general breakdown occurred to the earthing system in a house, industry or office.
The electronic circuits of this invention can be employed in many electrical installation in different Countries, by varying properly some electrical components of the circuits, such as the resistance values, the features of the signallers or the commercial leds. Brief description of the drawings
Some drawings show the electronic circuits proposed by this invention, and in particular those relative to the electrical schemes 101, 102, 103, 104, 105, 106, 107, 108 and 109, represented respectively by figures 1, 2, 3, 4 and 5, 11, 14, 16 and 17 and in the specific tecniques by figures 6, 7, 8, 9, 10, 12, 13, 15, and 18.
All the schemes showing the electronic circuits 101-109 are represented inside a dotted line poligon; the features of the electrical components, the resistance and capacity values, the kind of diods, leds and transistors are into the poligon as well; external to the poligon there are some numbers indicating the reference to explain the content of the invention. The dotted line poligons can be compared to some glass plates containing the components of the circuits.
The other drawings show the way to install the circuits in a tool taken as a sample (figures 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, and 31). The drawings of figures 32, 33 and 34 describe a plug inserted into an electrical user, figures 35 and 36 describe the plug provided with a cable 2P+E + earthing/test conducer/signaller and figures 37 and 38 show a safety earthing test accessory assembled on an appliance. The last graph (figure 39) clarifies the principle of function of the electronic circuits in systems EE and EN. Modes for carryng out the invention
Before describing the invention it is important to remember the general principle of working by the electronic circuits in systems EE and EN , as they are connected to the electrical power point (that are phase (L3) and neutral (N) supplied by the transformer cabin-distribution system) and to the user's earthing (PE) -230V-50/60 Hz-, as shown in fig. 39.
The electronic circuits, either in the case of green led activation or no activation, or alternatively by red led or sonoric buzzer activation, work by shutting (or not) the breakdown ring between the consumer's earthing and the earthing of the electrical transformer cabin (as shown in figure 39, electronic circuit of scheme 102, connected to phase (L3) in terminal point 12, to neutral (N) in terminal point 13 and to earthing (PE) in terminal point 14). The electronic circuits and their connection to the electrical users, like a socket, through phase, neutral and earth, allow the circulation of the current into a branch of the circuit that activates the green led. This happens by shutting the breakdown ring, through the consumer's and the cabin earthing. Any interruption in the protection conductor, equipotential node, or earthing contact tube of a socket, and also the lack of the same earthing installation will not allow the shutting of the breakdown ring, and consequently the current will not circulate in any branch of each circuits (of this invention), thus activating or rather alarming the green led signaller.
Figures 1 and 6 show the electronic circuit, electrical scheme 101, composed of resistances 1 and 2 of variable values, for instance between 330 and 68 KΩ, and of light signal or led 3; the terminal points 4, 5 and 6 of the electronic circuit must be connected to the phase, neutral and earth respectively in order to work. The light signaller 3 has the following features, indicative but not absolute: conical signaller or neon hollow with an incorporated or not resistance, supplying of 230 V, triggering tension 50 V, coulored light, or alternatively the features of a common commercial led diode. The light signaller or green led diode 3 will be activated when it finds the presence of a network tension with another means, if the monophase electrical installation 230V between phase and neutral, provided with protection conductor connected to the circuit of scheme 101, is also connected to an earthing.
Figures 2 and 7 shown the components of the electronic circuit, scheme 102, which are attributed indicative, but not absolute, values mentioned below: - a 68 KΩ resistance 7, a 68 KΩ resistance 8, a 68 KΩ resistance 9, a green led diode signaller 10, a yellow led diode signaller 11.
The terminal points 12, 13 and 14 of the electronic circuit, (scheme 102), must be connected to the phase, neutral (of electrical supply) and earth respectively, in order to work.. The light signaller or green led 10 will be activated when it finds the presence of a network tension by the yellow led 11 activation, if the electrical installation 230V between phase and neutral (provided with protection conductor) connected to the circuit of scheme 102, is also connected to an earthing.
Figures 3 and 8 show the components of the electronic circuit, scheme 103, which are attributed indicative, but not absolute, values mentioned below:
- a 68 KΩ resistance 15, a 10 KpF- 100V capacitor 16, four diodes 17, 1 8, 19 and 20 type 1N4148, a common commercial yellow led diode 21, a common commercial green led (flashing light) diode 22, a 68 KΩ resistance 23, a
100 KΩ resistance 24.
The terminal points 25, 26 and 27 of the electronic circuit
(scheme 103) must be connected to the phase, neutral and earth respectively, in order to work. The light signaller or green led flashing light 22 will be activated when it finds the presence of a network tension by the yellow led 21 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor (and earthing), connected to the circuit of scheme
103, is also connected to an earthing.
Figures 4 and 9 show the components of the electronic circuit, scheme 104, which are attributed indicative, but not absolute, values mentioned below:
- a 1 KΩ resistance 28, a 2 KΩ resistance 29, a bridge of diodes 30 type 1N4148 x 4, a bridge of diods 31 type 1N4148 x 4, an opto insulator 32, or a photolinker type SFH 611-3, a yellow led diode 33, a green led diode 34, a red led diode 35, a 56 KΩ resistance 36, a
68 KΩ resistance 37, a 56 KΩ resistance 38, a 1 KΩ resistance 39, a 68 KΩ resistance 40.
The terminal points 41, 42 and 43 of the electronic circuit (scheme 104) must be connected to the phase, neutral and earth respectively, in order to work. The light signaller or green led 34 will be activated when it fύ ds the network tension, by the yellow led 33 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor, connected to the circuit of scheme
104, is also connected to an earthing; in case of no connection to the earthing the flashing light red led 35 will turn on. Figures 5 and 10 show the components of the electronic circuit, scheme 105, which are attributed indicative, but not absolute, values mentioned below: a 56 KΩ resistance 47, a bridge of diodes 48 type 1N4148 X 4, a 4.7 KΩ resistance 55, a 68 KΩ resistance 50, a green led diode 51, a 1 KΩ resistance 52, an optoinsolator 53 of type SFH-611-3, a transistor 54 type BC237, a 4.7 KΩ resistance 55, a 12 KΩ resistance 56, a 47 KpF capacitor 57, a 47 KpF capacitor 58, a 12 KΩ resistance 59, a 4.7 KΩ resistance 60, a transistor 61 type BC237, an alarm piezoelectric buzzer 62, a 47 microfarad -50V capacitor 63, a yellow led diode 64, a 1 KΩ resistance 65, a bridge of diodes 66 type 1N4148 x 4, a 47 KΩ resistance 67, a 56 KΩ resistance 68.
The terminal points 44, 45 and 46 of the electronic circuit (scheme 105) must be connected to the phase, the neutral and the earth respectively, in order to work. The light signaller or green led 51 will be activated when it finds the presence of a network tension by the yellow led 64 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor, connected to the circuit of scheme 105, is also connected to an earthing; in case of no connection to the earthing the alarm piezoelectric buzzer 62 will turn on. Now we consider other electronic circuits for detecting the earthing and for testing the efficiency of the residual current circuit-breakers.
Figures 11 and 12 show the components of the electronic circuit, scheme 106, which are attributed indicative, but not absolute, values mentioned below: a 56 KΩ resistance 69, a 56 KΩ resistance 73, a bridge of diodes 74 type 1N4148 x 4, a 68 KΩ resistance 75, a 68 KΩ resistance 76, a green led 77, a 1 KΩ resistance 78, an optoinsolator 79 of type SFH-611-3, a transistor 80 type BC237, a 4.7 KΩ resistance 81, a 12 KΩ resistance 82, a 47 KpF capacitor 83, a 47 KpF capacitor 84, a 12 kΩ resistance 85, a 4.7 KΩ resistance 86, a transistor 87 type BC237, a buzzer 88, a 1 KΩ resistance 89, a red led diode 90, a 47 microfarad -50V capacitor 91, a yellow led diode 92, a 1 KΩ resistance 93, a bridge of diodes 94 type 1N4148 x 4, a 47 KΩ resistance 95. The terminal points 70, 71 and 72 of the electronic circuit (scheme 106) must be connected to the phase, neutral and earth respectively, in order to work.
The green led 77 will be activated when it finds the power tension by the yellow led 92 activation, if the electrical installation 230V between phase and neutral, provided with protection conductor connected to the circuit of scheme 106, is also connected to an earthing; in case of no connection to the earthing the sonoric alarm 88 and the red led 90 will turn on.
Figures 13 and 14 show the components of the electronic circuit, scheme 107, which are attributed indicative values mentioned below: a 68 KΩ resistance 99, a 1 KΩ resistance 100, a photoinsulator 110 of type SFH 611-33, a red led diode
111, a yellow led diode 112, a diode 113 of type
1N4148, a 68 KΩ resistance 114, a green led diode 115, a 68 KΩ resistance 116, a bridge of diods 117 composed of four diodes of type 1N4148. The terminal points 96, 97 and 98 of the electronic circuit
(electrical scheme 107) must be connected to the phase, neutral and earth respectively, in order to work.
The light signaller or green led 115 will be activated when it finds the presence of the network tension by the yellow led 112 activation, if the electrical installation 230 V between phase and neutral, provided with protection conductor, connected to the circuit of scheme 107, is also connected to an earthing; in case of no connection to the earthing the common commercial red led 111 will turn on. Figures 15 and 16 show the components of the electronic circuit, scheme 108, which are attributed indicative values mentioned below: a switch composed by a shunter 121, a 6.8 KΩ resistance 122, a 68 KΩ resistance 123, a 1 KΩ resistance 124, a green led commercial diode 125, a photoinsulator 126 type SFH-611-3, a red led diode 127, a yellow led commercial diode 128, a diode 129 type 1N4148, a 68 KΩ resistance 130, a 68 KΩ resistance 131, a bridge of diodes 132 type 1N4148 x 4, a 6.8 KΩ resistance 133, a 4.7 KΩ resistance 160. The terminal points 118, 119 and 120 of the electronic circuit (scheme 108) must be connected to the phase, neutral and earth respectively, in order to work. The light signaller or green diode led 125 will be activated when it finds the network tension by the yellow led 128 activation, if the electrical installation 230 V between phase and neutral, provided with protection conductor, connected to the circuit of scheme 108, is also connected to an earthing. In case of no connection to the earthing the the red led 127 will turn on. In order to ascertain the correct operation of the installation protected by Residual Current Circuit-Breakers (RCBB) it is necessary to test the fast intervention of the RCBB for instance within 40 milliseconds with a current of 250 milliampere ( this test is one of the instrumental tests suggested by some technical rules to verify the efficiency of the RCBB).
For this reason it is possible to install the electrical circuit of scheme 109, figure 17, also shown in details in figure 18, into complex electrical machines which need to be protected or on a tool, which gives the tension signal through yellow led diode 153 and the earthing signal through green led diode 148, it can also cause the intervention of the residual current circuit-breaker (RCBB) through a test push button 154, as in this case the current is higher than 30 mA for 20 ms. This is obtained by connecting terminal point 134 of the circuit of scheme 107 to the phase, terminal point 135 to the neutral, terminal point 136 to the earthing of an electrical installation 230V between phase and neutral with a protection conductor. The electrical circuit of scheme 109 is shown in details in figure 18. It is composed of : a 6.8 KΩ resistance 137, a phototriac 138 type MOC 3020, a phototriac 139 type MOC 3020, a 6.8 KΩ resistance 140, a 2.2 KΩ resistance 141, a transistor 142 type BC558, a 2.2 KΩ resistance 143, a 47 KΩ resistance 144, a 100 KΩ resistance 145, a 100 KΩ resistance 146, a 68 KΩ resistance 147, a green led commercial diode 148, a 68 KΩ resistance 149, a 4.7 microfarads capacitor 150, a bridge of diodes 151 type 1N4148 X 4, a 1.5 KΩ resistance 152, a yellow led commercial diode 153, a test push button 154, a 0.2 microfarad capacitor 155, a transistor 156 type BC238, a transistor 157 type BC238, a 56 KΩ resistance 158, a 1 KΩ resistance 159.
By varying the 6.8 KΩ resistances 137 and 140, the 100 KΩ resistence 146 and the 0.2 microfarads capacitor 155 the waste current and the intervention time are respectively varied according to the equation V/R=I and t=R*C.
Now are described different ways to connect the electronic circuits of the invention to monophase electrical installations 230 V between phase and neutral, with protection conductor (and earth); this allows to realize the invention.
The electronic circuits of schemes 101, 102, 103,
104 and 105 can be installed or assembed on a tool that has the feature of a plug without a cable, type
2P+E, as shown in figures 19, 20, 21, 22, 23, 24, and 25 in ratio of about 1:1. In this case the tools will have the features of the electronical circuits assembled on them.
Figures 19 and 20 show the find/earth tool 167 and the relative electronic circuit (figures 1 and 6 - scheme 101), composed of resistances of variable value 1 and 2i for example between 330 and 68 KΩ , connected to the pins of phase 164 in terminal point 4 through conductor 161, and of neutral 165 in terminal point 5 through conductor 163, and of the light signaller or green led diode 3 connected to the pin of earthing 166 in terminal point 6 through conductor 162.
The green led diode 3 (figure 20) will turn on if the socket connected to the find/earth revealer tool 167 is also connected to an earthing; if there is no connection to the earthing the green led 3 will not be activated. As shown in the electrical scheme 101 of figures 1 and 6, the electronic circuit described is simmetrical and so the phase and the neutral can be inverted, this allows the insertion of tool 167 (that has the features of a plug without a cable as shown in figures 19 and 20) into the socket in question in any way.
The find/earth tool 167 of figure 19 and 20 will be activated when it finds the presence of a network tension on the socket in question with another means (tool or indicating instrument). The find/earth tool 167 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a current higher than 10 mA, as the resistances 2 and 1 have values between 330 and 68 KΩ, for instance .
In figures 21 and 22 are shown the find/earth tool 171 and the relative electronic circuit (figures 2 and 7 - scheme 102), connected to the pins of the phase in terminal point 12 through conductor 168, of the neutral in terminal point 13 through conductor 169, and of the earth in terminal point 14 through conductor 170. The green led diode 10 (figure 22) will turn on if the socket connected to the find/earth revealer tool 171 is also connected to an earthing; if there is no connection to the earthing the green led 10 will not be activated. The electronic circuit of scheme 102 is electro-simmetrical and so the phase and the neutral can be inverted, this allows the insertion of the tool into the socket in question in any way.
The tool 171 reveals the power tension of a socket through the yellow led diode 11, and it is made in a way that does not involve the residual current circuit breakers installed upstream the sockets with a residual current higher than 10 mA.
Find/earth tool 172 is shown in figure 23 while the electronic circuit is in figures 3 and 8 (scheme 103); it is connected to the phase pin of tool 172 (plug 2P+E without a cable) in terminal point 25, to the neutral pin in terminal point
26 and to earth pin in terminal point 27. The flashing green led diode 22 (figures 3, 8, 23) will turn on if the socket connected to the find/earth revealer tool 172 is also connected to an earthing; if there is no connection to the earthing the green led 22 will not be activated. The electronic circuit of scheme 103 is electro-simmetrical and so the phase and the neutral can be inverted, this allows the insertion of tool 172 into the socket in question in any way. The tool 172 reveals the line's network tension of a socket through the yellow led diode 21. The find/earth revealer tool 172 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a residual current higher than 10 mA.
Find/earth tool 173 is shown in figure 24 while the electronic circuit is in figures 4 and 9 (scheme 104); it is connected to the phase pin of tool 173 in terminal point
41, to the neutral pin in terminal point 42 and to earth pin in terminal point 43.
The electronic circuit (scheme 104) is made of electric and electronic components activating different coulored leds with fixed or flashing light and namely: fixed light yellow led 33 for eventual tension in the socket; fixed light green led 34 for the earthing connection; or alternatively - flashing light red led 35 for no earthing connection. The electronic circuit of scheme 104 is electro-simmetrical, this allows the insertion of tool 173 into the socket in question in any way.
Find/earth tool 173 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a residual current higher than 10 mA.
Find/earth tool 174 is shown in figure 25 while the electronic circuit is in figures 5 and 10 (scheme 105); it is connected to the phase pin of tool 174 in terminal point 44, to the neutral pin in terminal point 45 and to earth pin in terminal point 46.
The (electro-simmetrical) electric circuit (scheme 105) is made of electric and electronic components that can activate different coulored leds with fixed light or a sonoric alarm, and namely: fixed light yellow led 64 for eventual tension in the socket; fixed light green led 51 for the earthing connection; or alternatively sonoric piezoelectric buzzer 62 for no earthing connection.
Find/earth tool 174 is made in a way that does not involve the residual current circuit-breakers installed upstream the sockets with a residual current higher than 10 mA.
Figures 28 and 29 show (in ratio of about 1:1, and in a longitudinal section and externally) the electrical safety and RCBB/test and earthing/test tool 177 that uses the electronic circuit of scheme 108 of figures 15 and 16, and allows to make a verification on sockets protected by residual current circuit-breakers with a current of 30 mA. The RCBB/test and earthing/test tool 177 detects: - the network tension by yellow led diode 128; the presence or the absence of connection the socket in which it inserted, to the general earthing of the electrical installation in question, by green led diode 125 or alternatively red led diode 127; the efficiency of the RCBB used as a protection of the socket with a test current of about 30 mA, through a test switch 121 composed by a shunter. The tool 177 is obtained by connecting terminal point 118 of the electronic circuit (scheme 108) to the phase pin (of plug type 2P+E) by conductor 180, terminal point 119 to the neutral pin by conductor 178 and terminal point 120 to the earth pin by conductor 179, as shown in figure 28.
The resistances 122 and 133 of 6.8 KΩ each can be replaced or varied in a way obtaining tools that supply test current equal to the current of the residual current circuit-breaker (according to the equation R=V I, with R indicating the power tension and I is the current), for example 10 mA, 30 mA, 50 mA, 300 mA and other values. Figures 30 and 31 show the tool 181 composed of the electric circuit of scheme 109 (figures 17 and 18), which gives the signal of tension through yellow led 153 and the signal of earthing connection through green led 148, it can also cause the intervention of the residual current circuit- breakers through test push button 154, if the current is higher than 30 mA for 20 ms. This is obtained by inserting the electrical circuit of scheme 109, figure 17, in a plug type 2P+E and connecting terminal point 134 of the electronic circuit (scheme 109) to the phase pin (of the plug), terminal point 135 to the neutral pin and terminal point 136 to the earth pin (as shown in figure 30).
By varying the 6.8 KΩ resistances 137 and 140, the 100 KΩ resistence 146 and the 0.2 microfarads capacitor 155 (figs.
17 and 18) the waste current and the intervention time are respectively varied according to the equation V R=I and t=R*C.
As the circuits represented in schemes 101, 102, 103, 104, 105, moreover 106 and 107 of figures 1, 2, 3, 4, 5, moreover 11 and 14 can work in parallel, they can be inserted into any plug with cable type 2P+E (as shown in figure 32, scheme 107) in this way it is obtained a plug provided with earthing/test served and connected to a tool or an household appliance. This is obtained by connecting terminal points 4, 5 and 6 or terminal points 12, 13 and 14, or terminal points 25, 26 and 27, or terminal points 41, 42 and 43, or terminal points 44, 45 and 46, or terminal points 70, 71 and 72, or terminal points 96, 97 and 98 respectively, to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to the conductor connected to the earth pin of a plug with cable (type 2P+E) inserted into a tool or a household appliance. For example the electronic circuit of scheme 107 can be inserted (as shown in figure 32) into any plug 182 with 2P+E cable 190, obtaining a plug with earthing/test 182 connected to a household appliance or user 183 (figure 33), this detects only whether the earthing of the socket, in which plug 182 (disclosed in figure 34 separated from the household appliance or user which is served) of the household appliance 183 is inserted, is connected to the general earthing system, as shown in figure 32 (scheme 107). This is obtained by connecting terminal points 96, 97 and 98 respectively to the conductor connected to phase pin 184 in point 187, to the conductor connected to the neutral pin 185 in point 188, and to the conductor connected to the earth pin 186 in point 189 of a plug 182 with cable 190 (type 2P+E) submitted to an appliance or user 183. The appliance or user 183 has, of course, the metallic carcass 191 connected to the earthing of cable 2P+E in point 192 of metallic mass 191. In this case red led diode 111, yellow led diode 112 and green led diode 115 will be placed on plug 182 (through the electronic circuit of scheme 107), each having the bulb placed on the external part of the plug.
Of course, by replacing the electronic circuit of scheme 107 with any other electronic circuit among those in question, the earthing/test plug displays the features of the circuit installed.
The circuits represented in schemes 101, 102, 103, 104, 105, moreover 106 and 107 of figures 1, 2, 3, 4, 5, moreover 11 and 14 can be inserted into any plug with cable type 2P+E by connecting their terminal points to any point of the phase, neutral and earth conductors, (as it has been shown previously), obtaining cables and extensions with plug and socket provided with a permanent control of the earthing; that is an earthing/test. Therefore cables and extensions will be provided with a permanent control of the earthing that is the earthing/test displaying the features of the circuit installed, and in particular of its own light signallers.
Moreover as the circuits represented in schemes 101, 102, 103, 104, 105, 106 and 107 of figures 1, 2, 3, 4, 5, 11 and 14 can work in parallel, they can be inserted into any plug with cable type 2P+E of an appliance, of a tool or of an electrical user (as shown in figure 35, scheme 104) obtaining a plug provided with cable type 2P+E+earthing/test conductor/signaller. This is obtained by connecting terminal points 4, 5 and 6 or terminal points 12, 13 and 14, or terminal points 25, 26 and 27, or terminal points 41, 42 and 43, or terminal points 44, 45 and 46, or terminal points 70, 71 and 72, or terminal points 96, 97 and 98 respectively, to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to the metallic carcass of the household appliance or electrical user. The electrical connection of the appliance to the metallic carcass is obtained by passing a signaller/conductor through the supplying cable (type 2P+E) of the appliance, with the phase, neutral and earth wires, and this is coincident with the connection point of the earthing conductor of the same supplying cable (as shown in figure 35 electronic circuit of scheme 104).
As an example, it is shown in figure 35 the electronic circuit of scheme 104 (and also in figures 4 and 9) that is inserted into plug 193 with cable 194 type 2P+E + earthing/test signaller/conductor 195. This result is obtained by connecting terminal points 41, 42 and 43 respectively, to the conductor connected to the phase pin in point 196, to the conductor connected to the neutral pin in point 197 and to point 198 of metallic carcass 199 of household appliance 200 (coincident with the connection point 198 of the earth cable 2P+E) as shown in figure 35 (the appliance 200 is represented in ratio of about 1:50 and the plug
193 in ratio of about 1:1). The electrical connection of the electronic circuit of scheme 104 to metallic carcass 199 of household appliance 200 is obtained by passing a signaller/conductor 195 through supplying cable
194 (which becomes of type 2P+E +conductor/signaller 195) of the appliance, with the phase, neutral and earth wires, and this is coincident with the connection point 198 of the earthing conductor of the same supplying cable 194 of the household appliance 200.
In order to supply the household appliance the plug 193 must be inserted into socket 201 with a tension of 230 V between phase (P) and neutral (N), and provided with the earthing (E).
In this case (using the electronic circuit of the scheme 104) the red led diode 35, the yellow led diode 33 and the green led diode 34 will be placed on plug 193 (shown not connected to appliance in figure 36) each with the bulb placed on the external part of the plug. Therefore the plug 193 with 2P+E cable 194 + earthing/test conductor/signaller 195 (cable 194 shown in figure 35 without the protecion envelope) is made of electric and electronic components able to activate different coulored leds with fixed or flashing light; they are: fixed light yellow led 33 for eventual network tension in the household appliance 200; fixed light green led 34 for the general earthing electrical installation connection of the metallic carcass 199 of the household appliance 200; or alternatively flashing light red led 35 for no general earthing electrical installation connection of the metallic carcass 199 of the household appliance 200.
By replacing the electronic circuit of scheme 107 with any other among those represented in schemes 101, 102, 103, 104,
105, 106, the plug with cable 2P+E+earthing/test conductor/ signaller connected to the appliance will have the features of the circuit installed, and in particular of their own signallers.
Another way to make the invention is to place the electronic circuits of the invention on an accessory (for example composed of a plastic plaque) assembled on the appliances, on the tools or on the electrical users which connection between the electronic circuits and the metallic carcass is directly made in any point of the metallic mass of the household appliance.
Figure 37 shows in ratio 2:1 the accessory 202 composed of a plastic plaque or resin (or another material electrically isolated from present metallic mass) with a rectangular shape which size is about 5x3x0.5 cm, and that can be attached, applied or screwed on the household appliances or electrical users through supports 203 and 204; this has the earthing test switch 205 (for example of type normally closed or open, double stable etc..) and the light led diodes. In particular the leds are: the (green led) 34 for the presence of an earthing, the (red led) 35 for its absence and the (yellow led) signaller 33 for the network tension, relating to electronic circuit of scheme 104 of the figures 4 and 9.
The connection of the circuit of the scheme 104 (figures 4 and 9) of the accessory 202 to the phase, to the neutral and to the metallic carcass of the appliance (or electrical user or tool) is shown in figure 38, and it is obtained electrically by connecting respectively: terminal point 41 to point 207 of the phase conductor of the appliance 206; terminal point 42 to point 208 of the neutral conductor of the appliance 206; terminal point 43 to any point 209 of the metallic carcass of the household appliance 206; this way it is obtained the safety earthig/test accessory 202, installed in the appliance 206, and that detects the connection of the same user 206 metallic carcass to the general earthing of the electrical installation, to which is connected by the cable 209 (shown in figure 38 without the envelope) and the plug 210 of type 2P+E provided with earth 211 connecting user 206 by a cable inserted into socket 212 (represented as a rectangle containing th letters P N E ), connected to the network tension.
The safety earthing/test accessory 202 has the electrotecnique features of its own electronic circuit, scheme 104 of the figures 4 and 9. In figure 38 it is shown the place 213 of the accessory 202 on the household appliance 206 where it will be fixed through supports 203 and 204, while figure 37 show the leds or light signaller 33, 34 and 35 protruding externally with their bulbs on the external part of accessory 202.
By replacing the electronic circuit of scheme 107 with any other electronic circuit among those represented in schemes
101, 102, 103, 104, 105, and 106 the safety earthing/test accessory assembled on the appliance will have the features of the circuit installed, and in particular of their own signallers. Industrial applicability
The industrial applicability of this invention depends on the fact that it makes possible a fast verification of the earthing particularly in a household, but also in an industrial environment, with a very low cost and by simple electronic circuits; this verification can, in fact, be carried out, with a simple tool by people not qualified in the scientific field of the electrical safety.
Moreover this invention introduces (and this is a new proposal) the possibility to install the safety earthing/test accessory provided with permanent or by test electronic control of the earthing on the household appliances.
The earthing/test accessory gives, in fact, the maximum safety for the use of the appliance in which it is installed.

Claims

Claims
1. Electronic circuits of schemes 101, 102, 103, 104 and 105 (and figures 1, 2, 3, 4, and 5, moreover 6, 7, 8, 9, and 10, where they are shown in details), claimed as electronic circuits displaying the use and employement features described.
The electronic circuits are joined by connecting terminal points in the order (4, 5, 6) (12, 13, 14) (25, 26, 27) (41, 42, 43) (44, 45, 46) of each circuit respectively to phase, neutral and earthing of a monophase electrical circuit 230 V. They are made of electrical and electronic components able to activate a green led, or other coulored led but different from those present in the same circuit, and/or different coloured leds with fixed or flashing light, and/or sonoric alarms and particularly: a) for the electronic circuit of scheme 101
- green led for the presence of the earthing connection; b) for the electronic circuit of scheme 102
- green led for the presence of the earthing connection;
- yellow led for the presence of network tension; c) for the electronic circuit of scheme 103
- flashing light green led for the presence of the earthing connection;
- yellow led for the presence of network tension; d) for the electronic circuit of scheme 104 - green led for the presence of the earthing connection;
- yellow led for the presence of network tension;
- flashing light red led for no earthing connection (for example of the plug or the metallic carcass of a household appliance). e) for the electronic circuit of scheme 105
- green led for the presence of the earthing connection;
- yellow led for the presence of network tension;
- sonoric buzzer for no earthing connection (for example of a plug or of the metallic carcass of the household appliance).
The electronic circuits do not cause the intervention of the residual current circuit-breakers assembled for protection on the circuits 230V between phase and neutral (and earth conductor) which are verified for the presence of the earthing connection. All the components of the electronic circuits are provided with indicative, but not restrictive values, that can be properly varied, even the kind of electrical component, according to the network tension which can be variable in different Countries.
2. Electronic circuits of schemes 106 and 107
(and figures 11 and 14, moreover figures 12 and 13 where they are shown in details), claimed as electronic circuits displaying the use and employ ement features described. The electronic circuits are joined by connecting terminal points in the order (70, 71, 72) (96, 97, 98) of each circuit respectively to phase, neutral and earthing of a monophase electric circuit 230 V. They are made of electrical and electronic components able to activate a green led (or other coulored led but different from those present in the same circuit), and or different coloured leds with fixed or flashing light, and/or sonoric alarms and particularly: a) for the electronic circuit of scheme 106
- green led for the presence of the earthing connection;
- yellow led for the presence of network tension;
- flashing light red led and sonoric alarm buzzer for no earthing connection (for example of a plug or of the metallic carcass of the household appliance). b) for the electronic circuit of scheme 107
- green led for the presence of the earthing connection;
- yellow led for the presence of network tension;
- red led for no earthing connection (for example of a plug or of the metallic carcass of the household appliance).
The electronic circuits do not cause the intervention of the residual current circuit-breakers assembled for protection on the circuits 230V between phase and neutral (and earth conductor) which are verified for the presence of the earthing connection. All the components of the electronic circuits are provided with indicative, but not restrictive values, that can be properly varied, even the kind of electrical component, according to the network tension which can be variable in different Countries.
3. Tools (167) (171) (172) (173) (174) in which the electronic circuits of claim 1 are installed (schemes 101, 102, 103, 104 and 105) they have the use and employement feature of a plug without a cable, type 2P+E (as shown in figures 19, 20, 21, 22, 23, 24 and 25).
The light signal or green led diode of each earthing test revealing/tool is activated if the socket in which it is inserted is connected to an earthing. The tools have the features of the electronic circuits installed on them, and in particular of their own light signallers.
The tools do not cause the intervention of the residual current circuit-breakers assembled for protection on the sockets that are tested for the presence of the earthing connection.
4. Tools (175) (176) in which the electronic circuits of claim 2 are installed (schemes 106 and 107) they have the features of a plug without a cable, type 2P+E (as shown in figures 26 and 27). The light signal or green led diode of each earthing test revealing/tool is activated if the socket in which it is inserted is connected to an earthing. The tools have the features of the electronic circuits installed on them, and in particular of their own light signallers. The tools do not cause the intervention of the residual current circuit-breakers assembled for protection on the on the sockets that are tested for the presence of the earthing connection.
5. Electrical safety and residual current prove earthing/test tool (177) (shown in ratio 1:1 in longitudinal section and externally in figures 28 and 29), which works with the electronic circuit of scheme 108, and claimed as an electronic circuit having the use and employement features described, allows the verification of the sockets protected by residual current circuit-breakers with a residual current of 30 mA. The tool (177) detects:
- the network tension presence by the yellow led diode (128);
- the presence or the absence of connection between the socket in which it is inserted and the general earthing system of the electrical installation, by the green led diode (125) or the red led diode (127);
- the efficiency of the residual current circuit-breakers placed for protection of the socket with a test current of 30 mA, by a switch (121), constituted by a shunter.
The resistances (122) and (133) of 6.8 KΩ each can be replaced or varied in a way obtaining tools that supply test current equal to the current of the residual current circuit-breakers (according to the equation R=V/I, with V indicating the power tension and I is the current), for example 10 mA, 30 mA, 50 mA, 300 mA and other values.
6. Tool (181) which uses the electronic circuit of scheme 109 (figures 30 and 31) (shown on detailes in figures 17 and 18), claimed as an electronic circuit having the use and employement features described, that gives the signal of tension by the yellow led diode (153) and the signal of the presence of the earthing by the green led diode (148), can also make intervene the residual current circuit-breakers when the current is higher than 30 mA for 20 ms, by a test push button (154). By varying the 6.8 KΩ resistances (137) and (140), the 100 KΩ resistence (146), and the 0.2 microfarads capacitor (155) the waste current and the intervention time are respectively varied according to the equation V/R=I and t=R*C.
7. Plugs provided with earthing/test served and connected to an appliance or electrical user, that are assembled through the electronic circuits reported on schemes 101, 102, 103, 104 and 105 of claim 1. The electronic circuits can be assembled by connecting terminal points in the order (4, 5, 6) (12, 13, 14) (25, 26, 27) (41, 42, 43) (44, 45, 46) of each circuit respectively to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to the conductor connected to the earth pin of any plug with cable 2P+E.
They detect by the activation of a light led, green or of another coulor but different the others present in the same circuit, whether the electrical connection socket of the household appliance is also connected to the general earthing system.
8. Plugs provided with earthing/test served and connected to an appliance or user, that are assembled through the electronic circuits reported on schemes 106 and 107 of claim 2. The electronic circuits can be inserted by connecting terminal points in the order (70, 71, 72) (96, 97, 98) of each circuit respectively to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to the conductor connected to the earth pin of any plug with cable 2P+E (as shown in figure 32 for plug 182 using the electronic circuit of scheme 107)
They detect by the activation of a light led, green or of another coulor but different the others present in the same circuit, whether the electrical connection socket of the household appliance is also connected to the general earthing system.
9. Cables and extensions with plug and socket provided with a permanent control of the earthing, namely earthing/test, as the electronic circuits of schemes 101, 102, 103, 104 and 105 of claim 1, working in parallel, can be inserted in any cable or extension provided with plug and socket of type 2P+E, by connecting terminal points (4, 5, 6) (12,13,14) (25, 26, 27) (41, 42, 43) (44, 45, 46) of each electronic circuit respectively to any point of the phase, neutral and earth conductors.
Cables and extensions have the features of the electronic circuit installed, and in particular of their light signallers.
10. Cables and extensions with plug and socket provided with a permanent control of the earthing, namely earthing/test, as the electronic circuits of schemes 106 and 107 of claim 2, working in parallel, can be inserted in any cable or extension provided with plug and socket of type 2P+E, by connecting terminal points (70, 71, 72) (96, 97, 98) of each electronic circuit to any point respectively of the phase, neutral and earth conductors. Cables and extensions have the features of the circuit installed, and in particular of their light signallers.
11. Plugs provided with cable of type 2P+E+ earthing/test conductor/signaller, as the electronic circuits of schemes 101, 102, 103, 104 and 105 of claim 1, can be inserted in a plug with cable of type 2P+E, by connecting terminal points in the order (4, 5, 6) (12,13,14) (25, 26, 27) (41, 42, 43) (44, 45, 46) of each electronic circuit respectively to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to the metallic carcass of the household appliance, tool or electrical user. The electrical connection of the electronic circuits to the metallic carcass of the household appliance is made by passing a conductor/signaller through the supplying cable (type 2P+E) of the same appliance, together with the phase, neutral and earth wires; this electrical connection coincides with the connection point of the earth conductor of the same supplying cable of the appliance (as reported in figure 35 referring to the electronic circuit of scheme 104).
The plugs 2P+T+earthing/test conductor/signaller have the features of the circuit installed, and in particular of their light signallers.
12. Plugs provided with cable of type 2P+E+earthing/test conductor/signaller, as the electronic circuits of schemes 106 and 107 of claim 2, can be inserted in a plug with cable of type 2P+E, by connecting terminal points in the order (70, 71, 72) (96, 97, 98) of each electronic circuit respectively to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to the metallic carcass of the household appliance, tool or electrical user. The electrical connection of the electronic circuits to the metallic carcass of the household appliance is made by passing a conductor/signaller through the supplying cable (type 2P+E) of the same appliance, together with the phase, neutral and earth wires; this electrical connection coincides with the connection point of the earth conductor of the same supplying cable of appliance.
The plugs 2P+E+earthing/test conductor/signaller have the features of the circuit installed, and in particular of their light signallers.
13. Electrical safety earthing/test accessories for household appliances using the electronic circuits of schemes 101, 102, 103, 104 and 105 of claim 1, installed by connecting in the order terminal points (4, 5, 6) (12,13,14) (25, 26, 27) (41, 42, 43) (44, 45, 46) of each electronic circuit respectively to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to any point of the metallic carcass of the household appliance, tool or electrical user (as reported in figure 38 referring to the electronic circuit of scheme 104). The accessories are composed of a plastic plaque or resin with a rectangular shape of size 5 x 3 x 0.5cm that can be attached, applied or screwed on the appliance through some supports, and which has the earthing/test switch and the light signallers installed.
Each electrical safety earthing test accessory, installed in the appliance, detects the connection between the metallic carcass of the appliance and the general installation earthing system through cable and plug 2P+E inserted into the relative socket.
This has the electrotechnique features of the circuits with which it is made and in particular of their light signallers.
14. Electrical safety earthing/test accessories for household appliances using the electronic circuits of schemes 106 and 107 of claim 2, installed by connecting in the order terminal points (70, 71, 72) (96, 97, 98) of each electronic circuit respectively to the conductor connected to the phase pin, to the conductor connected to the neutral pin and to any point of the metallic carcass of the household appliance, tool or electrical user. The accessories are composed of a plastic plaque or resin with a rectangular shape of size 5 x 3 x 0.5 cm that can be attached, applied or screwed on the household appliance through some supports, and which has the earthing/test switch and the light signallers installed. Each electrical safety earthing/test accessory, installed in the appliance, detects the connection between the metallic carcass of the appliance and the general installation earthing system through cable and plug 2P+E inserted into the relative socket.
This has the electrotechnique features of the circuits with which it is made and in particular of their light signallers.
PCT/IT1998/000330 1997-11-27 1998-11-23 Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users WO1999028755A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU22467/99A AU2246799A (en) 1997-11-27 1998-11-23 Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
ITPA97A000023 1997-11-27
ITPA970023 IT1297454B1 (en) 1997-11-27 1997-11-27 Earthing system detecting and residual current circuit breaker testing electronic circuit
ITPA980002 IT1306323B1 (en) 1998-02-05 1998-02-05 Earthing system detecting and residual current circuit breaker testing electronic circuit
ITPA98A000002 1998-02-05

Publications (3)

Publication Number Publication Date
WO1999028755A2 true WO1999028755A2 (en) 1999-06-10
WO1999028755A3 WO1999028755A3 (en) 1999-08-05
WO1999028755A9 WO1999028755A9 (en) 1999-09-10

Family

ID=26331764

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IT1998/000330 WO1999028755A2 (en) 1997-11-27 1998-11-23 Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users

Country Status (2)

Country Link
AU (1) AU2246799A (en)
WO (1) WO1999028755A2 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1447671A1 (en) * 2003-02-13 2004-08-18 Arnould, Roger Apparatus for monitoring an electric network
WO2005091002A1 (en) * 2004-03-19 2005-09-29 Global Spill Control Pty. Limited Electrical monitoring device
WO2007095887A2 (en) * 2006-02-23 2007-08-30 Obo Bettermann Gmbh & Co. Kg Apparatus for checking an electrical printed circuit board having a conductor track
GB2456799A (en) * 2008-01-24 2009-07-29 Andrew Abbott Residual current device test actuator

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3383588A (en) * 1965-08-23 1968-05-14 Daniel Woodhead Company Three prong circuit tester for electrical outlet sockets including a frame means formed with adjacent chambers for housing visual indicators
US3984765A (en) * 1974-09-27 1976-10-05 Rocci Jr Joseph A Power outlet circuit tester with ground fault testing capability
US4164701A (en) * 1977-09-06 1979-08-14 Austin Lloyd M Portable device for testing electrical wiring circuits and power tools and equipment
FR2421390A1 (en) * 1977-04-01 1979-10-26 Freckleton Donald Electrical connector correct wiring test and indicator circuit - uses bridge rectifier and relay with indicator circuit connected via respective switches to live, neutral and earth of main supply
US4394615A (en) * 1980-03-10 1983-07-19 Rocci Jr Joseph A Apparatus for testing the quality of the ground connection and the insulation quality in an electrical hand tool or the like
FR2662809A1 (en) * 1990-05-31 1991-12-06 Lecointe Didier Detector of breaks in conductors in a low-voltage electrical system with three phases and neutral
US5285163A (en) * 1992-05-07 1994-02-08 Liotta William A Electrical cable continuity and voltage tester
EP0715172A1 (en) * 1994-12-01 1996-06-05 Societe Anonyme Des Ets Catu Testing device for earthed wall socket

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3383588A (en) * 1965-08-23 1968-05-14 Daniel Woodhead Company Three prong circuit tester for electrical outlet sockets including a frame means formed with adjacent chambers for housing visual indicators
US3984765A (en) * 1974-09-27 1976-10-05 Rocci Jr Joseph A Power outlet circuit tester with ground fault testing capability
FR2421390A1 (en) * 1977-04-01 1979-10-26 Freckleton Donald Electrical connector correct wiring test and indicator circuit - uses bridge rectifier and relay with indicator circuit connected via respective switches to live, neutral and earth of main supply
US4164701A (en) * 1977-09-06 1979-08-14 Austin Lloyd M Portable device for testing electrical wiring circuits and power tools and equipment
US4394615A (en) * 1980-03-10 1983-07-19 Rocci Jr Joseph A Apparatus for testing the quality of the ground connection and the insulation quality in an electrical hand tool or the like
FR2662809A1 (en) * 1990-05-31 1991-12-06 Lecointe Didier Detector of breaks in conductors in a low-voltage electrical system with three phases and neutral
US5285163A (en) * 1992-05-07 1994-02-08 Liotta William A Electrical cable continuity and voltage tester
EP0715172A1 (en) * 1994-12-01 1996-06-05 Societe Anonyme Des Ets Catu Testing device for earthed wall socket

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1447671A1 (en) * 2003-02-13 2004-08-18 Arnould, Roger Apparatus for monitoring an electric network
FR2851338A1 (en) * 2003-02-13 2004-08-20 Arnould Roger APPARATUS FOR PERMANENT MONITORING OF AN ELECTRICAL NETWORK
WO2005091002A1 (en) * 2004-03-19 2005-09-29 Global Spill Control Pty. Limited Electrical monitoring device
WO2007095887A2 (en) * 2006-02-23 2007-08-30 Obo Bettermann Gmbh & Co. Kg Apparatus for checking an electrical printed circuit board having a conductor track
WO2007095887A3 (en) * 2006-02-23 2007-12-06 Bettermann Obo Gmbh & Co Kg Apparatus for checking an electrical printed circuit board having a conductor track
GB2456799A (en) * 2008-01-24 2009-07-29 Andrew Abbott Residual current device test actuator

Also Published As

Publication number Publication date
AU2246799A (en) 1999-06-16
WO1999028755A9 (en) 1999-09-10
WO1999028755A3 (en) 1999-08-05

Similar Documents

Publication Publication Date Title
US7168974B2 (en) Three phase lighted plugs and connectors for indicating the absence of at least one phase
US4691197A (en) Blown fuse indicator
US5285163A (en) Electrical cable continuity and voltage tester
US6948846B2 (en) Test apparatus for power circuits of an electrical distribution device
US7400225B2 (en) Electrical distribution device including protection for overheating conditions
US10897124B2 (en) High voltage site alarm signaling system and method for electrical cabinetry
US7713084B1 (en) Protective electrical wiring device and system
US10088500B2 (en) Combination test device
MXPA97000682A (en) Indicator of failure of installation in devices of protection of failure to tie
KR200396053Y1 (en) A portable electric tester
US4340826A (en) Low current pilot light and switch
WO1999028755A2 (en) Electronic circuits for detecting the earthing system and for testing the efficiency of residual current circuit-breakers connected to phase, neutral and earth of electrical users
CN114123094A (en) Fire protection switch and method
RU185776U1 (en) DEVICE FOR CONTROL OF OPERATION OF SOCKETS 220 V
US5485339A (en) Safety electrical assembly for electric power equipment
RU176977U1 (en) SAFETY AND OPERATION CONTROL DEVICE 220V
GB2344947A (en) Test apparatus for power supply networks
US6333625B1 (en) Fault localizing and identifying device for electric systems
GB1587043A (en) Multi-purpose test set for electrical appliances
RU197047U1 (en) Sockets
KR100455033B1 (en) Device for earthing status display
KR100376101B1 (en) Earth leakage detector testing device
KR200284070Y1 (en) Device for earthing status display
RU2126542C1 (en) Gear testing existence of voltage
GB2283870A (en) Electrical apparatus with fault indicator

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AU CA CN JP NZ SG US

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

AK Designated states

Kind code of ref document: A3

Designated state(s): AU CA CN JP NZ SG US

AL Designated countries for regional patents

Kind code of ref document: A3

Designated state(s): AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
AK Designated states

Kind code of ref document: C2

Designated state(s): AU CA CN JP NZ SG US

AL Designated countries for regional patents

Kind code of ref document: C2

Designated state(s): AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

COP Corrected version of pamphlet

Free format text: PAGE 9, DESCRIPTION, REPLACED BY A NEW PAGE 9; PAGE 1/21, DRAWINGS, REPLACED BY A NEW PAGE 1/21; AFTER RECTIFICATION OF OBVIOUS ERRORS AS AUTHORIZED BY THE INTERNATIONAL SEARCHING AUTHORITY

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA