AU2020449613B2 - Ramez very smart earthing system, short circuit and overcurrent protection - Google Patents
Ramez very smart earthing system, short circuit and overcurrent protection Download PDFInfo
- Publication number
- AU2020449613B2 AU2020449613B2 AU2020449613A AU2020449613A AU2020449613B2 AU 2020449613 B2 AU2020449613 B2 AU 2020449613B2 AU 2020449613 A AU2020449613 A AU 2020449613A AU 2020449613 A AU2020449613 A AU 2020449613A AU 2020449613 B2 AU2020449613 B2 AU 2020449613B2
- Authority
- AU
- Australia
- Prior art keywords
- load
- circuit
- terminal
- led
- resistor
- Prior art date
- Legal status (The legal status 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 status listed.)
- Active
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H83/00—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current
- H01H83/20—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current operated by excess current as well as by some other abnormal electrical condition
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/02—Details
- H02H3/04—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned
- H02H3/042—Details with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned combined with means for locating the fault
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention is a device that provides a smart accurate fault discrimination (either inner or outer leakage current, overload, over current and short circuit ) for every specific load of all types (either resistive, inductive, capacitive..) and cuts power for the faulty load only without affecting other parallel loads that are in the same circuit of the faulty load,so it assure the continuity of electric power for other loads.Beside, it helps the user for making fast maintenance by alerting the user for the position of the faulty load at this instant with music and light beside guiding the user for the type of fault (either inner leakage current, outer leakage current, overload, over current and short circuit), so the user can deal with faulty load safely and stop the music and light and then put it again to the service without making any effect to other loads.
Description
RAMEZ VERY SMART EARTHING SYSTEM , SHORT CIRCUIT AND OVERCURRENT PROTECTION
Prior art :
Traditional earthing system that contain earthing grid buried in the ground with it's accessors like earthing rod , earthing pit ,main earthing terminal, earthing grid conductors , in addition to the earth leakage circuit breaker that sense any leakage current to the earth and cut off the power of the circuit or the ground fault circuit breaker that cut off power of the circuit if it senses a difference between the current in the phases and the neutral.
Disadvantage of the prior art :
1- This traditional earthing system is very costly because it contain a lot of costly components with large quantities.
2- This traditional system requires regular maintenance for keeping the earthing resistance to minimum value for attracting any fault current to the ground and also for insuring the continuity of the earthing conductors from the load to the main earthing terminal to the earthing grid or earthing rod without any cutting point.
3-In case of current leakage in the load ,the earth leakage circuit breaker will shut of the power source for the whole panel that contain the fault (in case the earth leakage circuit breaker is on the main breaker of the panel )or the whole circuit that contain the load that have fault (in case the earth leakage circuit breaker is on the circuit branches ),so there is no accurate fault discrimination , beside no continuity of power supply for the rest loads that are in the same circuit of the faulty load but have not leakage .
4- In case of using ground fault circuit breaker with the main circuit breaker ,it will shut of the power for the whole panel in case there is slight unbalance in the operation of the loads on the phases or there is a current leakage and if it's used on a branch circuit ,it will shut of the
power for the whole circuit that have faulty load, so there is no accurate fault discrimination , beside no continuity of power supply for the rest loads that are in the same circuit of the faulty load but have not leakage.
The new in this invention:
1- It provides an accurate fault discrimination for every specific load (either resistive, inductive and capacitive) and cuts power of the faulty load only without affecting other parallel loads that are in the same circuit of the faulty load ,so it assure the continuity of electric power for other loads.
2- The invention provides fast maintenance for the fault , that after isolating the faulty load only ,it alerts the user for the position of the faulty load at this instant with music and light beside guiding the user for the type of fault (either inner leakage current, outer leakage current, overload, over current and short circuit) ,so the user can remove the faulty load safely where it has no power and is isolated and stop the music and light ,and deal with the faulty load separately and maintain it and then put it again to the service without making any effect to other loads.
3- This invention is very cheap compared to the traditional earthing system and compared to it's advantages due to it's few simple components.
Component
1-Live conductor of the feeding source that feed the sockets or the loads with power. l'-live terminal that is connected to the live conductor of the feeding source through fuse (5) and normally closed contact of dc relay(21) , where this live terminal is connected directly to the load or connected to the live terminal of the socket that feed the load.
2-Neutral conductor of the feeding source. 2'-Neutral terminal that is connected to the neutral terminal of the load directly or connected to the neutral terminal of the socket that is connected to the load.
3-Earth terminal for the socket or the load(which is connected to the body of the load) from one side and from the other side connected to the gate of a thyrstor through a resistor.
4-Copper joint that connects the live conductor of the feeding circuit with the live conductor that is connected to the live terminal of the socket or the live terminal that feds the load.
4'- Copper joint that connects the Neutral conductor of the feeding circuit with the neutral conductor that is connected to the neutral terminal of the socket or the neutral terminal that is connected to the load.
5-Fuse. 6- Resistance. 7- Resistance. 8- Resistance. 9-
Resistance. 10- Resistance. 11- Resistance. 12- Resistance. 13- Buzzer.
14-Dc led. 15- Triac . 16- Transistor. 17- Switch. 18- Switch. 19- Ac led. 20- Triac. 21 - Dc relay. 22- Buzzer. 23- DC led. 24- LDR .25- Thyristor.
26-Battery with switch on/off. 27- Push button normally closed. 28- Normally closed contact in the dc relay(21) with contact 28'. 29- Switch.
30- Resistance. 31- Ac Led. 32- LDR . 33-LDR. 34- Switch. 35- Resistance. 36- Ac relay. 37- Dc led. 38- Normally open contacts in relay 36 with contact 38'. 39- power panel. 40- Disconnect switch. 41- load connected to the three terminals (live, neutral and earth ). 42- live bus bar. 43-Neutral bus bar
Method of operation :
At normal operation the live conductor(l) and the neutral conductor (2) that comes from the power panel(39) , feeds many different parallel loads through a branch circuits, where each branch circuit feeds the load either directly through the circuit of the invention (Ramez very smart earthing, over current and short circuit protection ) or through a socket that contain circuit of the invention (Ramez very smart earthing, over current and short circuit protection ) , where the circuit of the invention (Ramez very smart earthing, over current and short circuit protection ) is connected to the back of the socket. where incase if there is any fault ( inner leakage current, leakage current from external, short circuit , overcurrent or over load ) in one of the loads that is branched from the main circuit (live conductorl& neutral conductor 2) through the circuit of invention ,the faulty load will be switched off only and alert the user for it's position and the type of it's fault by sound and light , while the other loads that are parallel with the faulty load will not switched off because the feeding circuit(l &2)will not be affected by the faulty load.
Even ,if one of the branched circuit from the main circuit(l&2) is connected to a socket ,and the this socket feeds many parallel loads ,and one of this parallel loads have a fault ,th is faulty load will be switched off only , while the other loads that are parallel with the faulty load will not switched off because the feeding circu it(l &2)will not be affected by the faulty load .
In Case an inner fault : where is a connection between the live conductor and the body of the load which is connected to the earth terminal (so there is a voltage on the body of the load )then a current will passes through the earth terminal in the socket to the gate of thyristor (25) which operates it ,so a current will pass from the battery (26) between anode and cathode of the thyristor and operates the relay (21) ,so the normally closed contact between contacts 28 and 28' opens which cuts the current that feeds the load through live terminal ( )
, while the other loads that feeds from the same circuit (live conductor 1 and neutral conductor 2) will still have power because they have not fault. Where by operation of relay (21) ,the buzzer (13) and the led lamp(14) will operate which indicate to the user the position of the load
that have fault ,then the user can come quickly to the load that have fault and remove the load from the socket (that is connected to terminal l',2' and 3) and press on the push button (27) to stop the sound of the buzzer (13) and reset the circuit to the normal operation ,so if the sound stops and light of led 14 becomes off after the user removed his hand from the push button (27) ,this means that the fault was inner fault in the load it self ,but if the sound doesn't stop, this means that the inner fault is in the socket it self or in the circuit that feeds it ,so the user can remove the socket and repair it ,so the user becomes aware of the reason and position of the fault easily and deal with it without cutting power to the whole main circuit (1&2 that feeds parallel loads )beside this fault will not affect other loads that feeds from the same circuit (live conductor 1 and neutral conductor 2 ).
In case an external fault , where a current or a live wire touches the conductive part of the body of a load , which is connected to the earth terminal (so there is a voltage on the body of the load )then a current will passes through the earth terminal in the socket to the gate of thyristor (25) which operates it , so a current will pass from the battery (26) between anode and cathode of the thyristor and operates the relay (21) ,so the normally closed contact between contacts 28 and 28' opens which cuts the current that feeds the load through live terminal ( )
, while the other loads that feeds from the same main circuit (live conductor 1 and neutral conductor 2) will still have power because they have not fault. Where by operation of relay (21) ,the buzzer (13) and the led lamp(14) will operate which indicate to the user the position of the load that have fault , beside due to the continuous fault current that comes from the external source ,the triac (15) will also operate which passes current between it's terminals ,so the dc led (37) will operate also beside led (14) ,so the user can come quickly to the load that have fault and know that this load have an external fault due to the operation of led (14) and led (37) beside the sound of the buzzer(13) , so he can deal with the external fault and remove it and then reset the operation of the circuit by pressing on the push button (27) , so if the sound stops and light of led 14 and 37 becomes off after the user removed his hand from the push button (27) ,this means that the external fault has been removed .
So the user will be aware of the reason and position of the fault easily and deal with it without cutting power to the whole main circuit(live conductor 1 and neutral conductor 2) beside this fault will not affect
other loads that feeds from the same circuit (live conductor 1 and neutral conductor 2 ).
In case there is a short circuit fault between the live terminal ( ) and neutral terminal (2') in the socket or in the load connected to it or an over current(overload) on the load ,the fuse (5) that feeds (l')will open and stop the current in the load that is connected to it only which stops the short circuit current or the overcurrent( overload) for protecting the load , while other loads that feeds from the main circuit(live conductor 1 and neutral conductor 2) in parallel with the faulty load will not be effected , where the user is guided to the position of the load that have short circuit by one of three different methods , first method as in fig 1 ; when the fuse (5) is cut due to short circuit or overcurrent or overload ,the led (19) will stop lighting ,so the dc current will pass through the triac(20) to the transistor (16)and operates it, so the buzzer (22) and led(23) will operate which alert the user for the position of the load or socket that have short circuit ,so the user can deal with the fault and then replace the fuse to reset the circuit, where the function of the triac (20) in the circuit is to not let the buzzer(22) or led(23) to operate incase there is a normal cut off in the main circuit (1 and 2) without occurrence of short circuit or over load or cutting off of the fuse (5). (Note :incase the user doesn't want to use the property of alerting of short circuit because it consumes power by the led(19),he can switch it off by the switch (18&17).
The second method as in fig 2: where in this method, we replaced only the triac(20) by the led(31) and two LDR(32&33) where the two Idr are connected in parallel and one side of them is connected to the emitter of transistor while the other side to the negative pole of the battery ,and they do the same function which is to not let the buzzer(22) or led(23) to operate incase there is a normal cut off in the main circuit (1 and 2) without occurrence of short circuit or over load or cutting off of the fuse (5).
(Note :incase the user doesn't want to use the property of alerting of short circuit because it consumes power by the led(19 &31),he can switch it off by the switch (29&17).
The third method as in fig3: where in this method, we replaced only the triac(20) by the ac relay(36) , where we connect it's coil from one side to the live conductor 1 of the main circuit and the other side of the coil is connected to the neutral 2 of the main circuit and connects it's normally open contact(38&38')in relay (36) to the emitter of the transistor from
one side and the other side to the negative pole of the battery , where the function of the relay (36) in the circuit is to not let the buzzer(22) or led(23) to operate in case there is a normal cut off in the main circuit (1 and 2) without occurrence of short circuit or over load or cutting off of the fuse (5).
The battery (26) in the three figures(figl ,fig2,fig3)have a switch that can let the user to switch off the battery to switch off the buzzer sound after knowing the location of the fault in order to deal with the fault in a quite environment especially for application that needs quite like hospitals.
By using this invention, we can substitute all circuit breakers in power panels (39) by disconnecting switches (40) only , because the circuit of invention will do all the functions of circuit breakers plus extra benefits which is cutting the faulty load only in the circuit without cutting power to the main circuit that feed the faulty load and other parallel loads beside guiding the user to the location and type of the fault , while the disconnecting switch will be used at the time of installing sockets only for disconnecting the power during installation.
Claims (1)
- Claims1-The invention is a device that provides an accurate fault discrimination for any specific load in a circuit, even if the circuit has a multiple parallel loads and cuts power for the faulty load alone without affecting other parallel loads in the same circuit and guide the user for the location of this fault and it's type, whether it's inner leakage current or external current or short circuit by sound and light.2- The invention consists of thyristor ,two triacs , battery ,dc relay, three dc leds , two buzzers, Idr, transistor, ac led, resistors , wires and two copper joints and fuse, where the fuse is branched from one side from live conductor of main circuit that feed from power panel and from the other side connected through a normally closed contact in the relay to live terminal of the load that will have it's feeding current from the main circuit that comes from power panel, And the anode of thyristor is connected to the neutral of the main feeding circuit that feed the load and the neutral of the load and the gate of the first triac and the terminal 1 of the other triac and the positive pole of the battery, while the cathode is connected to the gate through a resistor and also connected to one terminal of the coil of the relay while the other terminal of the relay is connected to the negative pole of the battery and there is a led and buzzer connected across the coil terminals, the gate of thyristor is connected to the body of the load either directly through resistor or through the earth terminal and a resistor and the terminal 1 of the first triac is connected also to the body of the load through the earth terminal and a resistor or directly through a resistor , where terminal 2 of the same triac is connected to the negative pole of the battery through led and resistor and a normally closed push button while the gate is connected to the postive pole of the battery and to the neutral of the main feeding circuit, the terminal 1 of the second triac is connected to the positive pole of the battery and to the neutral of the main source , while the terminal 2 of the triac is connected to a node that is connected to two branches where the first branch consists of a resistor that is connected to the gate of the transistor while the second branch consists of led and buzzer in series that are connected to the collector of the transistor and the gate of the triac is connected through a resistor to the live conductor of the main feeding circuit, the emitter of the transistor is connected to the negative pole of the battery through a normally closed push button and also connected to the Idr while the other side of the Idr is connected to the gate of the transistor, and the ac led is connected through switch to the fuse that is branched from the main feeding circuit and the other terminal is connected to the neutral of the main feeding circuit , where we can replace the second triac by two Idr and an ac led where one of the terminal of the ac led is connected across the neutral line of the feeding circuit and the other to live conductor of the feeding circuit through a resistor where the two Idr are connected in parallel that one side of the them is connected to the emitter of the transistor and the other side of them is connected to the negative pole of the battery, also the second triac can be replaced by an ac relay where the one of the terminals of the coil of the relay is connected to the live conductor of the main feeding circuit through a resistor while the other terminal is connected to the neutral of the main feeding circuit and a normally open contact of the relay is connected from one side to the emitter of the transistor and from the other side to the negative pole of the battery.3- The invention have a new technique for sensing any inner current leakage in the body of the load and cuts power to it alone without cutting power to other parallel loads in the same circuit and then alerting the user for the location of the load that have inner fault by sound and light , and this is achieved through a circuit which is connected as indicated in claim 2 of a thyristor which it's gate connected through a resistor to the earth terminal that is connected to the body of the load or connected directly to the body of the load and also connected to the cathode through a resistor while it's anode is connected to the positive pole of the battery while the negative pole is connected to the negative pole of the coil of a dc relay while the positive pole of the relay is connected to the cathode of the thyristor ,also there is a buzzer and dc led connected across the coil of the relay, and also a live conductor is branched through a fuse from main feeding circuit that feeds from power panel to feed load is coming across a normally closed contact in the relay ,so in case of inner fault , there will be a direct contact between the live wire that feed the load and the body of the load , so there will be a voltage on the body of the load then a current will passes from the body of the load to the gate of the thyristor which operates it so the dc relay operates which makes the the led and the buzzer to operates alerting the user for the fault , beside the normally closed contact that passes the live conductor to the load becomes open which cuts power on the faulty load only.4- The invention have a new technique for sensing any outer current leakage in the body of the load and cuts power to it alone without cutting power to other parallel loads in the same circuit and then alerting the user for the location of the load that have outer fault by sound and light , and this is achieved through a circuit which is connected as indicated in claim 2 of triac in which it's gate connected to the neutral of the main feeding circuit and to the positive pole of a battery while it's second terminal connected to the negative pole of the battery through a led and resistor and normally closed push button, while it's first terminal is connected through a resistor to the earth terminal that is connected to body of the load or connected directly through a resistor to the body of the load ,that in case of outer fault , there will be current on the body of the load , so there will be a voltage on the body of the load then a current will passes from the body of the load to the gate of the triac which makes it operates and passes current across it's terminals so the led that is connected with terminal two operates ,and also the thyristor in claim 3 will also operates due to the current in the earth terminal so it's relay and the led and buzzer across it will operates which alert the user for the presence of external fault by sound and lights of the two leds , beside the operation of the relay will make it's normally closed contact that connects live conductor branched from main feeding circuit to load becomes open which cuts power to the faulty load alone while other parallel load feed from main circuit will not be effected.5- The invention have a new technique for sensing any short circuit in the load and cuts power to it alone without cutting power to other parallel loads in the same circuit and then alerting the user for the location of the load that have this short circuit fault , and this is achieved through a circuit which is connected as indicated in claim 2 of triac in which it's gate connected to the live conductor of the feeding source through a resistor , while it's terminal 1 is connected to the positive pole of the battery and to the neutral of the feeding source and the terminal 2 is connected to a node that is connected to two branches where the first branch consists of a resistor that is connected to the gate of transistor while the second branch consists of led and buzzer in series that are connected to the collector of the transistor , while the emitter of the transistor is connected through Idr to the gate of the transistor and also connected to the negative pole of the battery, and an ac led is connected through switch to the fuse that is branched from the main feeding circuit and the other terminal is connected to the neutral of the main feeding circuit, that incase of occurrence of short ,the light of the ac led will shut off so a current will pass through the gate of the transistor so the buzzer and led connected to it's collector will operate alerting the user for the position of short circuit, where we can replace the triac by two Idr and an ac led where one of the terminal of the ac led is connected across the neutral line of the feeding circuit and the other to live conductor of the feeding circuit through a resistor and switch , where the two Idr are connected in parallel that one side of the them is connected to the emitter of the transistor and the other side of them is connected to the negative pole of the battery, also the triac can be replaced by an ac relay where the one of the terminals of the coil of the relay is connected to the live conductor of the main feeding circuit through a resistor and switch , while the other terminal is connected to the neutral of the main feeding circuit and a normally open contact of the relay is connected from one side to the emitter of the transistor and from the other side to the negative pole of the battery.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/IB2020/055131 WO2021240220A1 (en) | 2020-05-29 | 2020-05-29 | Ramez very smart earthing system, short circuit and overcurrent protection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU2020449613A1 AU2020449613A1 (en) | 2022-10-20 |
| AU2020449613B2 true AU2020449613B2 (en) | 2023-04-13 |
Family
ID=71016599
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU2020449613A Active AU2020449613B2 (en) | 2020-05-29 | 2020-05-29 | Ramez very smart earthing system, short circuit and overcurrent protection |
Country Status (2)
| Country | Link |
|---|---|
| AU (1) | AU2020449613B2 (en) |
| WO (1) | WO2021240220A1 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5493278A (en) * | 1994-05-10 | 1996-02-20 | Eaton Corporation | Common alarm system for a plurality of circuit interrupters |
| US5510949A (en) * | 1993-12-15 | 1996-04-23 | Eaton Corporation | Duty cycle filtered trip signalling |
| US6268989B1 (en) * | 1998-12-11 | 2001-07-31 | General Electric Company | Residential load center with arcing fault protection |
| US20030107854A1 (en) * | 2001-11-26 | 2003-06-12 | Mason Henry Hall | Circuit breaker with single test button mechanism |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101387730B1 (en) * | 2012-05-16 | 2014-04-18 | (주) 이오엠 | Trigger circuit and switching device using the same |
| CN107613626B (en) * | 2017-10-25 | 2021-01-26 | 苏州纽克斯电源技术股份有限公司 | Output detection protection circuit and alternating current electronic ballast for HID lamp |
| CN207382653U (en) * | 2017-10-25 | 2018-05-18 | 苏州纽克斯电源技术股份有限公司 | Output detection protection circuit and HID lamp AC electronic ballast |
-
2020
- 2020-05-29 AU AU2020449613A patent/AU2020449613B2/en active Active
- 2020-05-29 WO PCT/IB2020/055131 patent/WO2021240220A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5510949A (en) * | 1993-12-15 | 1996-04-23 | Eaton Corporation | Duty cycle filtered trip signalling |
| US5493278A (en) * | 1994-05-10 | 1996-02-20 | Eaton Corporation | Common alarm system for a plurality of circuit interrupters |
| US6268989B1 (en) * | 1998-12-11 | 2001-07-31 | General Electric Company | Residential load center with arcing fault protection |
| US20030107854A1 (en) * | 2001-11-26 | 2003-06-12 | Mason Henry Hall | Circuit breaker with single test button mechanism |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2021240220A1 (en) | 2021-12-02 |
| AU2020449613A1 (en) | 2022-10-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10374410B2 (en) | Automatic reclosing alternating current circuit breaker | |
| CN106663937B (en) | Selective breaker | |
| JP2022508611A (en) | Solid state circuit breaker | |
| US7715158B2 (en) | Circuit interrupter with live ground detector | |
| US20160301204A1 (en) | Semi voltage dependent circuit breaker | |
| US11349297B2 (en) | Intelligent circuit interruption | |
| US20050243485A1 (en) | Leakage current detection interrupter with open neutral detection | |
| US6707651B2 (en) | ARC fault or ground fault or ARC fault/ground fault trip signal generator and trip unit employing the same | |
| US20070086141A1 (en) | Surge receptacle apparatus and power system including the same | |
| US20070159738A1 (en) | Receptacle providing sustained excessive voltage protection | |
| AU2014220405B2 (en) | New leakage protection method and device having live/neutral wire identification function | |
| US20060198067A1 (en) | Extension cord having open neutral during fault detection trip | |
| CN114123094A (en) | Fire protection switch and method | |
| US4067054A (en) | Over-voltage protection | |
| RU2638571C1 (en) | Three-phase alternating current substation | |
| US8098465B1 (en) | AFCI breaker providing protection for multiple branch circuits in an electrical panel | |
| TWI542113B (en) | System protection device, electrical circuit switching device, and power supply system | |
| CN110445124B (en) | Device for coupling insulation monitoring device to ungrounded power supply system | |
| AU2020449613B2 (en) | Ramez very smart earthing system, short circuit and overcurrent protection | |
| KR840001584B1 (en) | Wireless emergency power interrupting system for multibranch circuits | |
| US6867703B2 (en) | Safety-protection circuit | |
| US8605395B1 (en) | Dual plug adapter and household high current apparatus | |
| RU2629958C1 (en) | Device for current protection of electrical installation | |
| CN210468782U (en) | Power line leakage protection device, electric connection equipment and electrical appliance | |
| CN210041314U (en) | Power line leakage current detection protection device and electric equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FGA | Letters patent sealed or granted (standard patent) |