CN2146071Y - Neutral potential shifting integrated protection circuit breaker - Google Patents

Abstract

The utility model discloses a neutral conductor potential integrated protection circuit breaker which belongs to a low voltage electric protection device, comprising a combination of a miniature air breaker, and a neutral shift production device with a shape similar to the breaker, or a neutral shift electricity leakage production device. The closing of the breaker and a releaser with high sensitivity of the protection device are driven by a lever. The action control power supply of the lever is an accident signal, and thus the reliability is high. The control circuit of the lever which is isolated by magnetism is voltage impact resistant and current impact resistant. The neutral conductor potential integrated protection circuit breaker which has four protection functions of short cut, overload, electricity leakage, neutral conductor potential shift is suitable for a system with single phase load of three phase and four line.

Description

Neutral potential shifting integrated protection circuit breaker

The utility model relates to a kind of low-voltage variation electrical equipment; it is a core with the protection of neutral line potential shift; be furnished with defencive functions such as short circuit, overload, electric leakage, promptly it is a kind of four kinds or three kinds of protected modes to be combined in integrated protection circuit breaker, (the middle partial switch) that forms in the device.

In industry and civilian power circuit; because of short circuit divides overload or electric leakage; regular meeting causes power consumption equipment to be burnt; accidents such as person electric shock cause very big loss to people's lives and properties; the protective device that suitable short circuit, overload, electric leakage etc. should be installed clearly instructs in native land man in power circuit in the electrical design standard, and obtained practical effect.And the neutral line is not caused enough attention and the reliable perfect protective device of release as yet because of various faults causes the accident of mid-point potential offset.

In three-phase four-wire low-voltage electric power system (TN-C, TN-S, TN-C-S, TT ground connection standard), be minimum in normal equilibrium potential difference in service between the neutral line and the ground, but in case broken neutral line, a relative ground circuit take place; Perhaps during accident such as center line and phase line misconnection; just produced voltage between neutral line N and the earth or the protective wire PE; this voltage is ruined equipment sometimes, the body of hurting sb.'s feelings; middle partial switch is set when voltage is above above 50V between N line and the ground; make faulty circuit according to the anti-time limit characteristic automatic disconnection; voltage is healed the high time that disconnects faster (weak point), then is that quick-break is with protection equipment and personal safety when voltage reaches 220V.

The protection switch of forming by application for a patent for invention " protector for null line breaking " and small air circuit breaker; the perhaps protection switch of forming by protector for null line breaking, earth leakage protective device, small air circuit breaker; though to having improved the safety guarantee of circuit, because patent of invention " disconnected zero protection " has following two big shortcomings in design:

1, in this " disconnected zero protection ", the neutral line or phase line are directly connect the lightning impulse resistant poor performance through electronic component and the earth.

2, the dropout power of used release is 25VA(50V0.5A in should " disconnected zero protection " device) power consumption is big; can only directly use power supply as the dropout accessory power supply; the state of control power supply directly influences the reliability of switch motion, and the big cost height of small product size.So the application of product and maintenance have been subjected to having a strong impact on.

The purpose of the utility model is: at " protector for null line breaking " shortcoming on circuit design; adopt novel circuit design and structural design; fundamentally overcome the shortcoming of protector for null line breaking; make performance stable, reliable " neutral line potential shift integrated protection circuit breaker ", to guarantee line security.

The utility model is to realize above-mentioned purpose like this:

In view of the present low-tension network overwhelming majority is that TN system (three-phase and four-line protection connecting to neutral system) and TT system (three-phase and four-line protective earthing system) " in inclined to one side " switch is got neutral line accident voltage over the ground and moved.(neutral line N and protective wire PE only link at the power supply neutral point to the TN-S system; but PE iterative earthing; the then not reproducible ground connection of N) and (working earthing of protective earthing and power supply neutral point of TT system; connect without conductor; separate) get the voltage between N line and the PE line; (distribution line of sending from power supply is the neutral line and the PEN of protective wire for unifying for the TN-C form to the TN-C-S system; but enter building change into the TN-S system be the neutral line and protective wire be N and PE divide open) this earth resistance that independently connects the utmost point of voltage that then should get between N line and the independent grounding utmost point E should be greater than 100 Europe, and should be less than 15 meters apart from protective wire iterative earthing device ground middle distance.

Detected accident voltage from zero to the 45V reliably (assurance) be failure to actuate, when reaching 50V, answer action message; This setting voltage is the ability of bearing voltage during by the safe voltage limiting value of 1EC prescribed by standard and household electrical appliance short circuit, the issuable permission potential shift of zero line in the time of will escaping normal operation simultaneously and deciding.

In partial switch be set at operate time: be not more than 5 seconds the operate time of 50V; Voltage rises, and also shorten gradually operate time, is set in when rising to 98V in 0.2 second, fixes on when rising to 220V in 0.5 second, and voltage and time are anti-time limit characteristics, make its selectivity that reaches protection equipment at different levels in the power network and reliable in action.

This device is not that the neutrality fracture itself is shielded; but just shield when after neutral line fracture back or other faults take place, causing dangerous consequences; as long as neutral line current potential is no more than permission (safety) value, circuit still can continue safe operation, and electric network reliability is improved.

This installs used release is high-sensitive, and power demand is minimum, thus needn't use accessory power supply, and utilize detected accident voltage self to make the operation power supply, improved reliable in action.Testing circuit by small-sized high insulated isolation transformer, with electrical network have only getting in touch of magnetic; between the neutral line and the ground; a lightning protection component is set; enable to stand the surge voltage of 7KV and the thunder and lightning of 5KA power frequency continued flow capacity, therefore anti-interference and lightning protection properties meets Guoan's standard of shock resistance type protection electrical equipment fully.

This device adopts highly sensitive magnetictrip, and this drop-away current is about 15mA, and dropout power is about 300 μ VA; so just can finish the dropout task reliably with faint Control current; and in partially protection and the shared release of earth leakage protective, dwindled volume greatly, reduced cost.

This group switch comprises short circuit overload, disconnected in, four kinds of functions of electric leakage design and indicate memory in order to indicate inhomogeneous fault actions in order to differentiate out of order character spy after switch motion, as figure four, the fault type of switch motion is difference as follows:

1. short circuit and overload: combined floodgate handle F jumps off, and other are motionless.

2. action partially in: combined floodgate handle F jumps off, and general reset key E takeoffs, memory indicator C upset (being red).

3. leakage switch action: combined floodgate handle F jumps off, and general reset key E takeoffs, memory indication C do not overturn (for white).

Description of drawings and middle partial switch circuit analysis

Fig. 1 is the block diagram of circuit; N is that neutral line PE is that the protection ground wire is when accident takes place; midpoint potential raises; detect isolated location and detect signal; send into the inverse time lag voltage selecting circuit through the rectification anti-clutter circuit; trip signal is sent into polarization through action indication memory and is discharged release, makes the circuit breaker deenergization through lever, the upset of the memory of action indication simultaneously.If use the formula group switch, when leak current fault, C1, C2 have electric leakage signal (being sent here by zero-sequence transformer) more, directly feed release action (without action indication memory) through the electric leakage delay circuit.

Fig. 2 is a schematic diagram, in bias-voltage send into isolating transformer B1, B2 and once be connected to lightning protection component R12 and play that anti-thunder and lightning is capable to involve anti-tampering effect, after full-wave rectifier D3-D6 rectification, capacitor C 4C5C6 and choke B2 are with the clutter elimination, and purified signal is sent into each delay circuit; Resistance R 10R4 and controllable silicon SCR 2 formed the control circuit of 45V, and the dividing potential drop deficiency on the following R11 of 45V is so that the SCR2 conducting, so the following release Q of 45V does not thread off.The BG2 loop is basic delay circuit, signal through the R7C2DW1 voltage stabilizing after the R5R6 dividing potential drop power to BG2; R4C1 is a delay circuit, delay time after four seconds, send into SCR1 by D1 and make operation indicator L, rectifying tube D2, release Q, SCR1 enters the condition of conducting, BG1 and R1R2R3 form the shunt of R4, when voltage reaches 98V, R4 adds that this makes time-delay shorten to dropout in 0.2 second at once along separate routes, R8R9 and G form the quick-break circuit, when voltage reaches 220V, at 0.05 second internal trigger controllable silicon SCR 1(SCR2 this moment was conducting), by on can find out release the action control that is subjected to above four kinds of circuit with cooperate, make it guarantee to be failure to actuate below the 45V, action in 4 seconds during 50V, action in 0.2 second during 98V, the inverse time-lag performance (C3 is a filter capacitor) of action in 0.05 second during 220V.

Fig. 3 is primary circuit (or 220V380V circuit), and L is the neutral line for phase line N, and PE is the protection ground wire, and N, L are through small air circuit breaker (Z), and zero-sequence transformer (C) is to outlet N ', L '.Annotate: if three-phase and four-line L2L3 through air circuit, after also through zero-sequence transformer.C1, C2 feed the electric leakage delay circuit, C3, C4 are by leak test button (K1), resistance (R1) can leak electricity to move and test, N ' once arrives PE through isolating transformer (B1), in addition from L through trying inclined to one side button (K2) resistance (R2) and B1 once to N ', partially action test in can carrying out, the B1 secondary of isolating transformation in control circuit power supply partially.

It is international advanced and leading domestic product that the small air of this group switch adapted opens circuit, protection switch after the cooperation is small and exquisite, of a tightly knit structure, reasonable, multiple functional, can be combined into series switch as required and be applied in various occasions, during the middle partial switch of single-phase two-level structure series has partially, in the short circuit, overload, leakage, the quadruple defencive function, it is contained in each single-phase branched line head end in the three-phase and four-line main line, and circuit and the power consumption equipment later to comprehensive protection device shield; When it was used as total protection, its residual current protective unit can have selectivity.If single-phase duplexure user has only first class of protection device (as grange), then its residual current protective unit adopts the instantaneous operation type." the middle partial switch " of three-phase and quadrupole structural series have short circuit, overload, in partially triple functions (should be contained in the head end of each single-phase duplexure because of earth leakage protective) this " middle partial switch " be installed in three-phase four-wire system main line end, circuit and single-phase electric devices in each later single-phase duplexure of switch are shielded.

Fig. 4 is single-phase bipolar " middle partial switch " profile; in partially and earth leakage protective device (1); its vertical view becomes L shaped; its end view becomes convex shape; so that be combined into one with small air circuit breaker (2); before small air circuit breaker line outlet, add the irdome locus of protecting that and install zero-sequence transformer and outlet terminal additional; make group switch turnover line position corresponding up and down; be convenient to wiring; especially the three-phase and quadrupole switch only being added left side protective device box just can cooperate with four miniature circuit breakers; and corresponding up and down turnover line, can significantly reduce overall dimension; reduce cost.

Test button (3) on upper end plate, having partially, leak(age) test button (4), outage memory indicator (5), in partially indication reset key (6), release reset key (7), miniature circuit breaker combined floodgate handle (8), circuit breaker outlet holding screw (9), group switch outlet holding screw (10), PE wire hole (11), N1L1 wire hole (12), the screw (13) of threading a needle, fixed screw forms a whole more than (14), has the dovetail groove (on circuit breaker) of standard to be fixed in arbitrarily on card or the distribution panelboard down.

Claims (5)

1, a kind of comprehensive protection switch of forming by protector for null line breaking, small air circuit breaker, the perhaps comprehensive protection switch of forming by protector for null line breaking, earth leakage protective device, small air circuit breaker, it is characterized in that: in the comprehensive protective circuit breaker of this neutral line potential shift, the neutral line potential shift protective device that replaces protector for null line breaking, its operation with thread off without accessory power supply but by detecting trouble signal power supply that isolating transformer detects; This neutral line potential shift protection switch, shell (shape) vertical view of its neutral line potential shift protective device and earth leakage protective device becomes L shaped, its end view becomes convex, be combined into one with the small air circuit breaker, before small air circuit breaker line outlet, add the locus of protecting irdome that and install zero-sequence transformer and outlet terminal additional, make group switch into and out of the upper and lower correspondence of line position; Described neutral line potential shift protective device; by detecting isolated location (transformer) detection signal; send into the inverse time lag voltage selecting circuit through the rectification anti-clutter circuit; the release signal is sent into polarization through action indication memory and is discharged release; make the circuit breaker deenergization and make action indication memory upset comprise the protection switch of earth leakage protective device through lever, electric leakage signal directly feeds release through electric leakage delay circuit or instantaneous operation circuit.

2, neutral line potential shift integrated protection circuit breaker according to claim 1, it is characterized in that: described neutral line potential shift protective device, neutral line potential shift signal is sent into isolating transformer (B1), the secondary of B1 is via rectifier (D3-D6) rectification, and purified signal sent into control circuit behind capacitor C 4, C5, C6 and choke elimination clutter; Control circuit comprises the 45V circuit of 1. being made up of resistance (R10, R11) and controllable silicon SCR 2; 2. BG2 basis timing circuit signal is pressed to its power supply through R7, C2DW1 voltage stabilizing after R5, R6 divide); 3. after R power, the time-delay of C1 delay circuit, send into SCR1 by D1 and make indicating device L, rectifying tube D2, release Q, controllable silicon SCR 1 enter turn-on condition; 4. form R4 0.2 second circuit along separate routes by BG, R1, R2, R3; 5. the quick-break circuit of forming by R8, R9, G, thus guarantee that 45V is failure to actuate, during 50V 4 seconds, 0.2 second, the inverse time-lag performance of deferred action in 0.05 second during 220V during 98V.

3, neutral line potential shift integrated protection circuit breaker according to claim 1 and 2 is characterized in that: described isolating transformer (B1) secondly is parallel with ability on the coil and is not less than the over-voltage protection element that the 5KA power frequency is read flow, 7KV voltage.

4, neutral line potential shift integrated protection circuit breaker according to claim 1 and 2 is characterized in that: the shared highly sensitive release of described neutral line potential shift protective device and earth leakage protective device.

5, neutral line potential shift integrated protection circuit breaker according to claim 1 and 2; it is characterized in that: neutral line line potential shift protective device; occur with a typing assembly; perhaps add earth leakage protective device, or form the composite type series protection switch of required function arbitrarily with the air switch of typing.

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