JPS58133118A - Leakage breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Technical field of invention] TECHNICAL FIELD The present invention relates to the modification of an earth leakage interrupter.

[Technical background of the invention]

As shown in FIG. 1, the circuit configuration of a conventional earth leakage interrupter is such that a load 3 is connected to a power source 1 via a main circuit contact 2 to form a main circuit.

Furthermore, the nine auxiliary transformers whose primary end 4a is connected in parallel to the main circuit have their secondary end 4b connected to the input end of a single-phase full-wave rectifier 5, and the output of this single-phase full-wave rectifier 6. Power supply end P1*
A smoothing capacitor and a series circuit of a tripping coil 7 and a thyristor 8 connected in parallel with the smoothing capacitor are connected to N1.

On the other hand, the zero-phase current transformer 9 with the main circuit as the primary side has its secondary end connected in parallel to the input terminals M and B of the control circuit 11 by connecting a resistor 10 in parallel between its lines. There is. Also, the control circuit 1
The input power terminal P wealth.

N1 is connected to the output terminals P, N1 of the single-phase full-wave modulator 5 through a resistor 12 in series to obtain a control power source.

In this control circuit 1, when a leakage fault occurs on the negative 1li13 side of the main circuit, an F'i current is generated on the secondary side of the zero-phase current transformer 9, and this is an alternating current sine wave l11E This is a current signal, but it is converted into a voltage of 1g by the resistor 10, and by inputting this voltage signal, the capacitor 13 connected to the -1 power supply terminal N and the hold terminal H is charged. When the voltage at both ends exceeds the set value, the thyristor 8 is output from the output terminal S.
A current (r-) is applied to the dart, igniting the size 9/β, energizing the tripping coil 7, and releasing the catch to open the main contact 2.

In addition, this earth leakage interrupter operates a thermal relay (not shown) to open the main circuit contact 2 in case of an overcurrent accident.
For instantaneous operations such as short circuits, an electromagnet (not shown) operates to open the main circuit contacts 2. Note that 14 is a pressure-inserted linear surge absorbing element connected in parallel to the primary end 4a of the auxiliary transformer 4, which absorbs power supply noise and clips and clips it.

Next, the detailed structure and operation of the above-mentioned control circuit port will be explained with reference to FIG. 2.

The input terminal of a stabilized power supply circuit 11& which outputs a reference voltage is connected to the + side power supply terminal P3 of the control circuit port, and the series circuit of resistors 11bl and Jlb is connected to the output terminal of this stabilized power supply circuit 11m. , - side power supply terminal N, is grounded to form a closed circuit.

The input electron A to which the secondary side of the zero-phase current transformer 90 at the control circuit port is connected is connected to the terminal arm of the converter 11cO+, and one end of the terminal Ile is connected to the resistor 11b1.
and the resistor 11b. In addition, the input terminal B of the control circuit U is connected to the resistors JJbl and Jlb.
, and one end of the series circuit are connected to one side power supply terminal N3.

The output end of the converter Alator 11C is connected to a hold capacitor HK to which a capacitor 12 is connected via a resistor JJd.

In addition, 11 is a hysteresis circuit having a hysteresis characteristic that outputs an output signal when the input voltage is Vl (1) and outputs an output signal when the input voltage is Vt, (vH, > VL), as shown in Figure 3. , the cathode of a thyristor 111 is connected as an input to the hysteresis circuit 11, the toode of this thyristor 111 is connected to the hold terminal H and the cathode of a zener diode I1g, and the anode of this zener diode JJg is connected to the thyristor 111. JJf
is connected to the y-t. Also, the hysteresis circuit 11
The output terminal of ・ is connected to the terminal S of the control circuit port via the resistor 11b.
and is connected to the dart of thyristor 8.

The operation of the control circuit U described above is such that when an earth leakage accident occurs in the load 3@, an AC sine wave current signal caused by the earth leakage accident that occurs in the secondary of the zero-phase current transformer 9 is converted into a voltage signal by the resistor 10. Convert. When the voltage across this resistor 10 becomes equal to or higher than the voltage obtained by dividing the output voltage of the stabilizing power supply circuit 11a of the control circuit by the resistors 11b1 and 11b when the AC sine wave is a positive side cow wave, the converter Al regulator A logic Krepel "l" signal is generated at the output of Llg, and this signal charges the capacitor 13 connected to the control circuit via the resistor.The voltage across the zero-order resistor 100 becomes an AC sine wave. When the voltage becomes lower than the voltage obtained by dividing the stabilized power supply circuit output 11m of the control circuit U by the resistor 11b1 and the resistor 11b3, the converter Al regulator Ilc outputs logic, Frepel@0''.
is output, and the charge in the capacitor J1 is discharged via the resistor 11d and the condenser 110.

Again, the voltage across the resistor 100 changes the output voltage of the stabilized power supply circuit 11m to the resistor 11b! and resistor 11b.

When the voltage is divided by , and the voltage exceeds the voltage, an output signal of "Lono, Krepel@l" is generated at the output of the converter 11, and this signal charges the capacitor 11 again via the resistor 11d.This cycle is as follows. Repeatedly, when the voltage across the capacitor 130 gradually rises and exceeds the Zener voltage of the Zener diode 115, the r-g!
! A signal is supplied to turn on thyristor llf.

Therefore, the capacitor 13 is discharged via the thyristor Ilt, and becomes the input signal S of the hysteresis circuit 11. This input signal VS causes hysteresis (b) path 11.
sends a dart signal to the thyristor 8 via the resistor 11b.

As mentioned above, the hysteresis circuit 11 has the characteristics shown in FIG.
Even if it rises to M and then becomes low to some extent, for example to ■L, the hysteresis circuit 11 is connected to the thyristor 8 via the resistor 11k. send the number. This reliably turns on the thyristor 8, excites the tripping coil 7, releases the catch, and opens the main circuit contact 2.

[Problems with background technology]

In the earth leakage breaker configured as described above, the time from the occurrence of an earth leakage accident until the main circuit contact 2 opens, that is, the delay time, can be adjusted by varying the capacitance of the L capacitor 13. , when the capacitance of the capacitor 13 is increased, the control circuit is placed in the path where the capacitor 13 discharges.
The control circuit I is usually a one-chip, 7" IC.
A nine-swivel resistor 111 is provided inside this one-chip IC.
The thyristor 111 has a very small current capacity of only a few tens of microamperes, and the capacitance of the thyristor 111 cannot be increased because the rounding current capacity provided inside the control circuit 11, which is a one-chip IC, will be destroyed by this. is 0.05M
It could only be increased to about F, and the effect of time delay was almost negligible, and the effect was only at the level of noise absorption.

The control circuit 11 using this thyristor 111 could only be used as a high-speed type leakage interrupter that does not require a time delay. In addition, in order to maximize the effect of time delay, it was necessary to provide a separate circuit using an IC designed specifically for the effect of time delay, which increased the number of parts for peripheral circuits and increased costs. . Furthermore, in the case of high-speed type earth-leakage interrupters, the circuit configuration was completely different from that of Tokinobu, so there was a drawback that standardization of high-speed types and Tokinobu products was significantly hindered.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and allows high-speed operation type and time delay operation type to be realized without newly providing an IC for a control circuit for time delay, and also enables easy product standardization. The purpose is to provide an interrupter in case of electrical leakage.

” [Summary of the Invention] The earth leakage interrupter according to the present invention achieves the above object by connecting a resistor connected between the secondary wires of a zero-phase current transformer to a first one, which determines the input voltage of a control circuit. A parallel circuit of a diode, a capacitor, and a second resistor is connected in series between the hold terminal H of the control circuit and the one-side power supply terminal Nt of the control circuit, and the first and second resistors are variable at the same time. The configuration should be such that it is possible.

[Embodiments of the invention]

An embodiment of the present invention will be described above with reference to the drawings. Fourth
The figure is a circuit diagram showing an embodiment of the earth leakage interrupter according to the present invention. In FIG. 4, a power source 1 is connected to a load 3 via a main circuit contact 2 of the earth leakage interrupter to form a main circuit.

The auxiliary transformer whose primary end 4a is connected in parallel to the main circuit has its secondary end 4b connected to the input end of the single-phase full-wave rectifier 5, and the output end PIINI of this single-phase full-wave rectifier 5. A smoothing capacitor 6 and a series circuit of a tripping coil 1 and a thyristor 8 connected in parallel to the smoothing capacitor 6 are connected to the smoothing capacitor 6 .

On the other hand, the main circuit is the primary side, and the first variable resistor J of the double variable resistor LA is connected between the lines on the secondary side of the nine zero-phase current transformer 9.
jm are connected in parallel and connected to input terminals A and H of the control circuit.

The power supply terminal PIINm of the control circuit U is connected to the output terminals P1 and Nl of the single-phase full-wave rectifier 5 through a resistor 12 in series to obtain a control power supply.

Further, the anode of the diode 16 is connected to the hold terminal H of the control circuit, and the cathode is connected to the capacitor 13 which is connected in series with this diode 1#.
The second variable resistor J5& of the front two-way Nicho variable resistor 14 is connected in parallel, and is connected to one side power supply NsK of the control circuit U.

The detailed circuit diagram of the control circuit is the same as that of the conventional example shown in FIG. 2, so the explanation thereof will be omitted.

In addition, this power supply interrupter has a thermal relay and an electromagnet (not shown), and the thermal relay is activated when an overcurrent accident occurs and fully opens the main circuit contact 2, and the electromagnet is activated in the event of an instantaneous operation such as a short circuit. 2, the main circuit contact 2 is opened.

Next, the operation of the above-mentioned earth leakage interrupter will be explained with reference to FIG.

When an earth leakage accident occurs on the load 3 side of the main circuit, the earth leakage detection current is detected by the zero-phase current transformer 9, and the first Or low transformer resistor 1
6m and converts it into a stain pressure signal.

Depending on the magnitude of this voltage level, the control circuit 11- determines whether or not there is an abnormality. Since this was explained in detail in the conventional example shown in FIG. 2, it will be omitted here. When a certain voltage, that is, the manual operating voltage of the control circuit 11, exceeds about 501 V, a stain current flows from the hold terminal H of the control circuit 11 and charges the capacitor IJ via the diode 1#. When the voltage across the first variable resistor 1gm, that is, the input operating voltage of the control circuit 110, becomes approximately 5 mV or less, the capacitor IJ is charged, and the nine charges do not flow through the diode 16 to the multicontrol circuit 111C, but instead pass through the variable resistance of the first plane. discharge through the vessel J5kl.

Furthermore, when the voltage across the first variable resistor Jja, that is, the input operating voltage of the control circuit U exceeds approximately 5 mV, current flows through the diode IC (hold terminal H of the control circuit) and charges the capacitor 13 again. do. After repeating this cycle to charge and discharge the capacitor ISO, after a certain period of time, when the hold terminal H of the control circuit reaches a predetermined voltage, for example 2.5V, the output terminal S of the control circuit 11 releases the thyristor at'. -) Turn on the iris switch to send a signal, energize the coil 1, and release the catch to open the circuit contact 2.

Next, the operation of the double variable resistor will be explained. Variable resistor 15 of Ml of double variable resistor IJ
When m is rotated in a direction that increases the resistance value, the operating sensitivity current becomes smaller.

At this time, the second variable resistor 15b4 the first variable resistor 1
As in the case of 5a, since it rotates in the direction in which the resistance value increases, the time for the zero load of the capacitor 13 to discharge is shortened, making it difficult to discharge, and the delay time related to charging and discharging the capacitor 130 is shortened. This state corresponds to curve 3 in FIG. 5, in which the horizontal axis represents the sensitivity current 1 (mA) and the vertical axis represents the delay time T (m-.@). Conversely, a double variable resistor ISO cocoon 10-way variable resistor Jjm and a second variable resistor 5 J 6 b
When rotating in the direction of decreasing the resistance value, the sensitivity current 1 (m
A) and the delay time T (m srs ) change, and 2 in the figure.
．． 1, that is, as the motion feeling t[fi increases, the motion time also becomes slower.

According to the earth leakage interrupter of the Ill embodiment described above, the IIA degree current and the delay time can be set arbitrarily without the need to separately provide a dedicated IC to also provide the delay function. 1
The current leakage interrupter can be used in both high-speed operation type and delayed operation type, and can be standardized very easily.

(9) In this embodiment, a diode 16 and a second variable resistor 15b are provided in a portion not related to the input of the control circuit port to perform a time delay operation, so a new Even if it is necessary to connect a capacitor to the input, the effect on the islet connection is great because it has nothing to do with the input.

Furthermore, as shown in Fig. 6, in the power system, the power supply 1 is connected to the main leakage interrupter M, and as the load of the main leakage interrupter B, a branch leakage interrupter B is connected in parallel. The connected branch is interrupted due to electrical leakage! SC and connect these branch earth leakage interrupters B.

When loads Ja and 3b are connected to C, if the main branch leaks and interrupts, the branch leaks and interrupters B and C also slow down the delay time, that is, the branch leaks and interrupts @B, C. By making it a high-speed operating type, it is possible to achieve maintenance coordination in the power system.

(9) In the power system described above, the capacity of the capacitor 13 of each interrupter can be increased to increase the noise absorption effect against unbalanced negative current when large current is flowing, and also against noise. ,! I4wJ creation can be prevented.

Next, a second embodiment of the present invention will be described with reference to FIG. In Figure 6, the detailed circuit of the control circuit is as follows:
Since it is the same as the 1m2 diagram, its explanation will be omitted, and the fourth
The same parts as those in the figures are given the same reference numerals, and the explanation thereof will be omitted. The difference between the second embodiment and the #Il embodiment is that resistances 11m and 11b (J 7
b<, 17m) are connected in series, and this resistance 17m,
At the connection point between 17b, there is a double tap! A first tag switch 18a of the switch 18 is provided to enable switching of the value of the resistor 17 connected between the input terminals A and B of the control circuit L''.

Further, the nine diode 16 whose anode is connected to the hold terminal H of the control circuit, and the capacitor 13 connected between the one side power supply terminal N of the control circuit 11 are connected in series, and this diode 16 and the capacitor 77 Resistors 1pa and 1tb (1sb (19m)) are connected in series to the connection point between them, and the resistance 2.
Second tap changer 18b of continuous type tap, f changeover 11JJl
is connected to the resistor 1-, which is connected in parallel to the capacitor IS.
The value of can be changed.

Next, the operation of this second embodiment will be explained. In other words, if a load jllK earth leakage accident occurs when the two-way type switching device is in the state shown in Fig. 7, the secondary side of the zero-phase current transformer 90 will receive a zero of the AC sine wave due to the earth leakage. A phase current signal flows and is converted into a stain pressure signal by the resistor 11m. At the input of the control circuit, this voltage signal is compared with a reference voltage to determine whether or not there is a leakage, as shown in detail in FIG. In this case, when the resistor 11a with a large resistance value is connected between the lines on the secondary side of the zero-phase current transformer, the voltage across the resistor 77m, that is, the control circuit When the input voltage of J1 becomes approximately 5 mV or more, current flows from the hold terminal H of the control circuit, and an alternating current flows to the secondary side of the zero-order zero-phase current transformer 90, which charges the capacitor IJ via the diode 16. When one half wave of the sine wave flows and the voltage across the resistor 11m becomes less than the reference voltage of the control circuit W, no current flows from the hold terminal H of the control circuit, while the charge of the capacitor 13 is transferred to the diode. 16, no discharge occurs within the control circuit port, but discharge occurs mainly through the resistor 19m.

Next, when the positive half wave of the AC sine wave flows through the secondary side of the zero-phase current transformer 9 again, the voltage across the resistor J7 becomes larger than the reference voltage of the control circuit 1, and the capacitor 13 is discharged. do.

Continuing the above-mentioned cycle, when the voltage across the capacitor 130 exceeds a predetermined value, the control circuit port outputs its output terminal S.
A gate current is applied to the dart of the thyristor 8, the thyristor 1 is fired, the tripping coil 7 is energized, and the main circuit contact 2 is opened.

Next, the double tap changer U is switched so that the first tag changer 111 inserts a resistance job between the lines on the secondary side of the zero-phase current transformer 90. At the same time, the second tap changer U is switched. A resistor 19k is connected in parallel to the capacitor 13 by the tag switch Jlb. In this case, the input voltage at the control circuit port is smaller than that of the resistor JFm, and the discharge amount of the charge of the capacitor t73 is larger than that of the resistor 190. Therefore, the voltage across the capacitor 130 is set to a predetermined value. It takes a long time to reach the value, so the delay time is long.
A current leakage interrupter is realized.

As described above, the resistances 19m and 19b are switched by switching the double tag switch, and the control circuit U
The input voltage can be varied, and the charging time of the capacitor 13 connected to the front control circuit U can be varied, so there is no need to use a new IC chip for the control circuit 11, that is,
A low-cost earth leakage interrupter that can be used for both high-speed type and time delay type is realized with a small number of parts. In addition, the above second
This embodiment has the same effects as the first embodiment in addition to the above-mentioned effects.

Next, a third embodiment of the present invention will be described with reference to FIG. In FIG. 7, the detailed circuit of the control circuit II is the same as that in FIG. 2, so its explanation will be omitted, and the same parts as in FIG. 4 will be given the same reference numerals and their explanation will be omitted.

The third embodiment is different from Ml and the twentieth embodiment in that a resistor 2o is connected between the lines on the secondary side of the zero-phase current transformer 9, and the hold terminal H of the control circuit and the one-side power supply terminal N , a capacitor 13 and a resistor 21 are connected in parallel, and the resistance values of the resistors 20 + 21 can be arbitrarily exchanged.

In the third embodiment described above, when used as a time delay type earth leakage breaker, a relatively low resistance value is used for the resistor 20.21, and when used as a high speed type earth leakage breaker, a relatively low resistance value is used. uses resistors 20 and 21 with relatively high resistance values.

The operation and effect of the third embodiment described above are the same as those of the first and second embodiments, so a description thereof will be omitted.

The present invention described above is not limited to the above embodiments, but can be implemented with various modifications.

〔Effect of the invention〕

According to the present invention described above, there is provided an earth leakage interrupter that can be made into a high-speed operation type and a time delay operation type without the need to newly provide an IC for a control circuit for time delay, and which can facilitate product standardization. Can be provided.

[Brief explanation of drawings]

Figure 1 is a circuit diagram showing a conventional earth leakage interrupter, Figure 2 is a detailed circuit diagram of the control circuit shown in Figure 1, Figure 3 is a characteristic diagram of the hysteresis circuit shown in Figure 1, and Figure 4. is a circuit diagram showing the first embodiment of the earth leakage interrupter according to the present invention, FIG. 5 is a diagram for explaining the operation of the first embodiment shown in FIG. FIGS. 7 and 8 are circuit diagrams showing the second and third embodiments of the present invention. 1...Power supply, 2...Main circuit contact, 3...Load, 4
...Auxiliary transformer, 5...Single-phase full-wave rectifier, 6...
Smoothing capacitor 1", 1... tripping coil, 8... thyristor, 9... zero phase current transformer, 10... resistor, 11...
...Control circuit, 12...mK, JJ...Capacitor, 14...Non-linear width absorption element, 1B...Double variable resistor, 16...Diode, 11... resistance,
18...Double type Tano switch, 1 resistor, 20...
・Resistance, 21...Resistance. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 Figure 2 3H Figure 4 Figure 511 1 (mA) 61f 7th Section 8WJ Patent Office Concurrent Official Kazuo Sugi 1, Patent Application for Indication of Case No. 57-12859 No. 2, Name of the invention - Electric circuit breaker 3, Relationship with the amended case Patent applicant (307) aQ Shiba 1m Electric Co., Ltd. 4, Agent 6, Subject specification of supplementary IE 7, Contents of the amendment (1) The phrase ``Remove 9 and connect main circuit contact 2'' on page 3, line 14 and line 15 of the present specification is corrected to ``Remove 9 and connect main circuit contact 2.'' (2) “Grounded to” in the journal, page 4, line lO,
Correct it to "Connect to." (3) "Capacitor 12" written on the negative 20th line of s4 is corrected to "Capacitor 13". (4) On page 6, lines 6 and 7, "the voltage across the control circuit JJ is one half wave of an AC sine wave" is replaced with "the voltage across the control circuit 11 is the voltage across the control circuit 11". I am corrected. (5) The capacitance is 0.05MF as stated in the 8th negative 9th line of the same
JV, ``The capacitance is corrected to 0.05/IFJ.'' (6) ``To song iI3'' written on page 13, line 11, is changed to
"to curve 1," he corrected. (7) "2.1 in the figure" written in the 15th line of the 13th member,
Correct it to "2.3 in the figure". (8) "One half wave of the AC sine wave flows on the secondary side and the resistance" written in the 6th line of the 17th member is corrected to "resistance on the secondary side." (9) "Figure 187" written on page 19, line 5 of the same IJ,
Correct it to "Figure 8." (1
In Figure 8,” it is corrected.

Claims (1)

[Claims] Set the main circuit contacts by connecting the power supply to one of the nine main circuit conductors,
A load is connected to the other side, a nine-phase current transformer is provided with the main circuit conductor as the primary side, and a first resistor is connected between the lines on the secondary side, so that an earth leakage accident occurs in the load. When a single current detection current flows through the secondary side of the zero-phase current transformer, this current signal is converted into a voltage signal by the first resistor, and it is detected that this exceeds a preset reference voltage. In the earth leakage interrupter, which charges a DC current R capacitor under certain conditions, and when the internal voltage of this capacitor exceeds a predetermined value, it excites a tripping coil and activates a control unit that opens the main circuit contact. Connect the anode of a diode to the positive terminal 11 to which the capacitor/capacitor of the control section is connected, connect its cathode to the negative end of a parallel circuit of a capacitor and a resistor of m2, and connect the other end to the capacitor. An earth leakage interrupter having a configuration in which the values of the first and second resistors can be varied simultaneously by connecting to a negative terminal to which the resistor is connected.