JP2000222993A - Cumulative breaking current counter and breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cumulative breaking current counter capable of clearly judging the remaining life of a breaker and to provide the breaker. SOLUTION: This cumulative breaking current counter has a current detecting circuit A having detecting relays Lr1-Lrn corresponding to a plurality of current detecting ranges, in which all relays Lr1-Lrn in a current detecting range or less containing breaking current of a detecting object are operated; a plurality of counter circuits B installed according to a plurality of current detecting ranges; and a control circuit CON for operating the counter circuit B corresponding to the current detecting range in which breaking current is contained, by responding to the relays operating in the current detecting range in which breaking current is contained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cumulative breaking current counter and a circuit breaker applied to a power circuit breaker such as a GCB.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional example. That is, for example, two-phase currents of the three-phase circuits U, V, and W are detected by the main circuit CT and input to the current detection circuit A1. Current detection circuit A1
The relays Lr1 to Lr1 connected to the input current are full-wave rectified by the full-wave rectifier Z via the auxiliary CT, add these output voltages, and are respectively connected in series to mutually different resistors R1 to Rn.
Apply to Lrn. The resistors R1 to Rn are connected to the respective relays Lr1.
ＬLrn are sequentially set to operate in different current detection ranges, for example, 16 KA or more as a large current, 8 to 16 KA as a middle current, and 4 to 8 KA as a small current. Therefore, due to the circuit configuration, when the cutoff current is detected by the current detection circuit A1, one or a plurality of relays Lr1 to Lrn corresponding to the detected cutoff current or less operate. For example, when the current is small, only the relay Lr1 operates, when the current is medium, two relays Lr1 and Lr2 operate, and when the current is large, all three relays Lr1 to Lrn operate.

The counter circuit B1 includes relays Lr1 to Lr
The counters CNT1 to CNTn are connected so as to be directly operated by n contacts Lrr1 to Lrrn, respectively. Also, the relay Lr responds to the shut-off command of the shut-off control circuit.
s is activated, and the cut-off coil Tc is energized, so that the circuit breaker C
B is turned off. The operation of the relay Lrs activates the relay Lx1, turns on the contact Lxx1, turns on the counter CNTd, and counts the number of times the circuit breaker CB is cut off.

Lxx2 is a relay, Lxx2 is its contact,
C and Cc are capacitors, r1, r2, R, Ru and Rv are resistors, and Zn1 to Znn are Zener diodes.

[0005]

However, in this conventional example, the contacts L of the relays Lr1 to Lrn of the current detection circuit A1 are different.
rr1 to Lrrn, the direct electromagnetic counter CNT1 to CNT
Since NTn is driven, all the relays Lr1 and the like corresponding to the detected cut-off current value or less operate, and the counter CNT1 and the like connected to the contact also operate in the same manner. At the time of shutoff, all the counters CNT1 to CNTn operate.

[0006] For this reason, in the conventional example, information as to how many KAs were interrupted and how many times were unknown. In order to obtain the information, a separate calculation was necessary from the count values of the counters CNT1 to CNTn. As a result, in the conventional apparatus, the amount of wear of the contacts of the circuit breaker, that is, the remaining life of the contacts could not be clearly determined.

Accordingly, an object of the present invention is to provide a cumulative breaking current counter and a breaker which can clearly determine the remaining life of the breaker.

[0008]

According to a first aspect of the present invention, there is provided an accumulative interrupting current counter having a relay for detection corresponding to a plurality of current detecting ranges, wherein the current detecting range is equal to or less than the current detecting range including a current to be detected. A current detection circuit in which all the relays operate, a plurality of counter circuits provided corresponding to the plurality of current detection ranges, and in response to the relays operating in the current detection range including the cutoff current, A control circuit for operating the counter circuit corresponding to the current detection range including the cutoff current.

According to the first aspect of the present invention, even if all the relays corresponding to the current detection range or less including the cut-off current operate in the current detection circuit, the control circuit detects the current including the cut-off current. Since only the counter corresponding to the range operates, the number of cutoffs becomes clear for each current detection range of the cutoff current, and the remaining contact life of the circuit breaker can be clearly determined.

[0010] According to a second aspect of the present invention, there is provided an accumulative cut-off current counter.
2. The control unit according to claim 1, wherein the contacts of the relay are connected in series in order corresponding to the maximum to the minimum of the current detection range, a power source is connected to the maximum contact, and The contacts of the corresponding relays are constituted by normally open contacts and the counter circuit corresponding to the minimum current detection range is connected, and the other contacts are constituted by switching contacts, and the normally closed side is connected to each other in series. And the counter circuits of the corresponding current detection ranges respectively connected to the normally open side.

According to the cumulative interruption current counter of the second aspect, the same effect as that of the first aspect is obtained.

According to a third aspect of the present invention, there is provided an accumulative interruption current counter.
2. The plurality of steps according to claim 1, wherein the control means is constituted by a microcomputer, and a determination is made as to whether or not a contact point of the relay corresponding to the current detection range has been operated in descending order of the current detection range. And operating the counter circuit corresponding to the current detection range in each of the steps when it is determined that the current operation has been performed in the step.

According to the third aspect of the present invention, the same effects as those of the first aspect can be obtained.

According to a fourth aspect of the present invention, there is provided an accumulative cutoff current counter.
A current detection circuit for detecting a breaking current by dividing the current into a plurality of current detection ranges, and a cumulative life number per one breaking cycle for each of the plurality of current detection ranges is determined in advance according to a life curve of the circuit breaker; A pulse generator for generating a pulse of the cumulative life number corresponding to the current detection range in response to the detection operation of the current detection range, and a life accumulator for counting the number of generated pulses of the pulse generator. And a counter circuit.

According to the cumulative breaking current counter of the present invention, it is determined whether or not the cumulative value of the breaking current according to the life curve based on the count value of the life accumulating counter has reached a predetermined number of life times in all current detection ranges. Can be determined
Thereby, the remaining life can be clearly determined.

According to a fifth aspect of the present invention, there is provided a cumulative cut-off current counter,
Has a relay for detection corresponding to multiple current detection ranges,
A current detection circuit in which all the relays below the current detection range including the cutoff current to be detected operate; a plurality of counter circuits provided corresponding to the plurality of current detection ranges; and the cutoff current included Control means for operating the counter circuit corresponding to the current detection range including the breaking current in response to the relay operating in the current detection range; and the plurality of current detection ranges according to a life curve of the circuit breaker. Is determined in advance, and in response to the relay operating in the current detection range including the interruption current, the pulse of the cumulative life number corresponding to the current detection range is generated. And a counter circuit for accumulating a lifetime for counting the number of pulses generated by the pulse generator.

According to the cumulative cut-off current counter of the fifth aspect, the same effects as those of the first and second aspects are obtained.

According to a sixth aspect of the present invention, there is provided an accumulative interruption current counter,
In claim 3, the relay, the control means and the counter circuit are of a mechanical type, and the pulse generator is constituted by a logic circuit or a microcomputer.

According to the cumulative cut-off current counter of the sixth aspect, in addition to the same effects as those of the third aspect, even if the logic circuit or the semiconductor portion of the microcomputer is damaged due to mixing of surge or the like, the relay, the control circuit and Since the counter is mechanical, the counter circuit required for determining the remaining life is operable and thus has surge resistance. The use of a microcomputer enables communication with a higher-level system.

According to a seventh aspect of the present invention, there is provided a circuit breaker having the cumulative interruption current counter according to the first, second, third, or fourth aspect.

According to the circuit breaker of the seventh aspect, the same effect as that of the first, second, third or fourth aspect is obtained.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. That is, this cumulative cut-off current counter has a current detection circuit A, a counter circuit B, a control means CON, and a life accumulation counter circuit B4.

The current detection circuit A has detection relays Lr1 to Lrn corresponding to a plurality of current detection ranges, and all the relays Lr1 and the like below the current detection range including the cutoff current to be detected operate. . In the embodiment, the configuration is the same as that of the conventional example described above. That is, for example, two-phase currents of the three-phase circuits U, V, and W are detected by the main circuit CT and input to the current detection circuit A. The current detection circuit A performs full-wave rectification of the input current by the full-wave rectifier Z via the auxiliary CT, adds these output voltages, and outputs the different resistors R1
To Ln connected in series to Lr1 to Lrn, respectively.
Is applied. The resistors R1 to Rn are connected to the respective relays Lr1 to Lr.
n are sequentially different current detection ranges, for example, 16
KA or more, medium current 8-16 KA, small current 4
８8 KA. With such a configuration, the relay Lr1 and the like corresponding to the current detection range including the detected cutoff current value and the current detection range lower than the current detection range operate. Ru, Rv, and R are resistors, D is a diode, C is a capacitor, and Zn1 to Znn are Zener diodes.

A plurality of counter circuits B are provided corresponding to a plurality of current detection ranges. In the embodiment, the counter CNT1 includes a counter CNT1 for a small current, a counter CNT2 for a medium current, and a counter CNTn for a large current. r1 to r
n is a resistance.

The control means CON responds to the relay Lr1 or the like operating below the current detection range including the breaking current,
The counter circuit B corresponding to each of the current detection ranges is operated. The control means CON of the embodiment includes a relay circuit RL
And a pulse generator PU. The relay circuit RL is, for example, a mechanical type. The contacts Lrr1 to Lrrn of the relays Lr1 to Lrn are connected to the input portion of the relay circuit RL, and the counter (CNT1 to CNTn) corresponding to the current detection range including the detected cutoff current value is included. Is configured as follows so that only one of them operates. E is a DC power supply for supplying power to the control means CON.

FIG. 2 shows a relay of the control means CON.
The circuit RL and the pulse generator PU are shown in detail.
You. Here, n is 3. The relay circuit RL
-Each contact x interlocked corresponding to each of Lr1 to Lrn₁
~ X_ThreeCorrespond to the current detection range from the maximum to the minimum in order.
Connected to the row, the largest contact x_ThreeIs connected to power supply E,
Contact x that works in conjunction with the minimum current detection range₁Normally open
Composed of contacts and supports the smallest current detection range
To connect the counter circuit CNT1
x_Two, X_Three, Are composed of switching contacts and the normally closed
Connected in series with each other and
Counter circuit CNT2, CNT of corresponding current detection range_Three
Are connected. If it explains according to FIG. 2, a relay contact
Lrr1 to Lrr3 are each a relay X₁~ X_ThreeIn series
To the DC power supply E. Relay X₁
Normally open contact x₁, Relay X_TwoSwitching contact x_TwoNormally closed side
And relay X_ThreeSwitching contact x_ThreeThe normally closed sides of
One end connected to counter CNT ₁And relay X_FiveTo
Connected, the other end is relay X_FourNormally closed contact x_FourThrough
Connected to power supply E. Also relay X_TwoSwitching contact x
_TwoNormally open side is counter CNT_TwoAnd relay X₆Connect to
And relay X_ThreeSwitching contact x_ThreeNormally open side of counter C
NT_ThreeAnd relay X₇It is connected to the. Relay X_Four
Is a normally open auxiliary contact au responsive to the breaking operation of the circuit breaker CB.
x connected in series, connected to power supply E, shut off
As long as the switch CB does not shut off, that is, the auxiliary contact aux
Counter CNT1 etc. do not operate unless the circuit is opened
I have to. Also relay X₁Normally open contact x_1a, Relay X
_TwoNormally open contact x_2aAnd relay X_ThreeNormally open contact x_3aHaso
Timer contact T common to each₁Connected in series to the power supply
E is connected. Relay X ₁Normally open contact x_1bIs Thailand
The power supply E is connected in series to the power supply T. Also
Normally open contact Lrs of relay Lrs₁Is the operation count counter
Connected to the counter CNTd of the path B3 and to the power supply E.
Have been.

The operation of the relay circuit RL will be described. For example, breaking current of a small current detection range P ₁ flows through the 3-phase cable, the relay Lr1 is operated, the normally open contact Lrr1
Is closed, the relay X ₁ is operated. With this, normally open contact x
₁ , x _1a and x _1b are closed, the timer T operates to keep the relay X ₁ on for a certain period of time, and the relay contact x
_4, x _3, the counter CNT1 through x ₂ counts the cutoff number, at the same time the relay X ₅ is activated. If breaking current of medium current detection range P ₂ flows into 3-phase cable, which operates relay Lr1, Lr2 together, its contacts LRR1, Lr
r2 operates, relays X ₁ and X ₂ operate, and normally open contact x
_1a, x _2a is turned on, switching contact x ₂ is switched to the normally open side. Therefore counters CNT1 and relay X ₅ is not operated, the counter CNT2 and the relay X ₆ is operated. Similarly the large current detection range P _3, relay Lr1~L
r3 both operate, operates relay X ₁ to X ₃ that contacts Lrr1~Lrr3 operates, the normally open contacts x _1a ~x _3a is turned on, the switching contact x _2, x ₃ switched to the normally open side . Thus counter CNT1, the counter CNT2, the relay X _5, X ₆ is not operated, the counter CNT3 and relay X ₇ is operated.

The auxiliary contact aux is a normally open contact, and a normally closed contact x ₄ of the relay X ₄ unless opened (unless interrupted).
There therefore is off, in all of the current detecting range, the counter CNT1 to CNT3, and a relay X ₅ to X ₇ does not work. Similarly, in all the current detection ranges, the cut-off coil Tc is energized by the cut-off command of the cut-off control circuit to cut off the breaker CB, actuate the relay Lrs, close the normally open contact Lrs1, and operate the counter for the number of operations. The counter CNTd of the circuit B3 performs a counting operation. Timer T
Also, since operating at low current detection range P ₁ of the current, the same operation even other current detection range P _2, P _3.

The pulse generator PU determines in advance the cumulative number of lifespans per interruption for the current detection range according to the life curve of the circuit breaker CB, and responds to the relay Lr1 or the like operating in the current detection range including the interruption current. Thus, a pulse having a cumulative life number corresponding to the current detection range is generated. The life curve of the circuit breaker CB is, for example, as shown in FIG. Therefore, for example, the number of times of life accumulation per interruption number for the current detection ranges P _{1 to} P ₃ including the interruption current is set to the number according to the life curve of the circuit breaker CB, and these numbers are generated by the pulse generator PU. Then, the accumulated value is counted by a counter circuit B4 described later, and when the accumulated value reaches the set value, the life is determined. For example, the number of times of the cumulative life per one cut-off time is, for example, one when the cut-off in the small current detection range P ₁ of 4 to 8 KA is _one , and three times in the middle current detection range P ₂ when the cut-off is 8 to 16 KA. Assuming that the number of times of interruption of 16 KA or more, which is the large current detection range P ₃ , is 10 times, the accumulated value is, for example, 100
Is set in advance so as to determine that the life has expired.

A signal corresponding to the cutoff current in each of the current detection ranges P _{1 to} P ₃ is input from the relay circuit RL, and a pulse corresponding to the cumulative number of life is generated from the pulse generator PU every time the cutoff current is detected. . This pulse generator PU is constituted by, for example, a logic circuit as shown in FIG. That is, in FIG. 2, FF1 and FF2 are flip-flops, and Cr1 and Cr2 are input terminals of flip-flops FF.
1, clocks connected to the output terminals of FF2, CA1, C
A2 is a counter whose input terminal is a clock Cr1,
The output terminal of Cr2 is connected to the output terminal of Cr2, the output terminal is connected to the counter CNTe for accumulating the life, and the output terminal of the count-up signal is connected to the reset terminals of flip-flops FF1 and FF2. Normally open contact x ₅ is counter CN of the relay X ₅
The power supply E is connected in series with Te. Thus, the normally open contact x ₅ of the relay X ₅ is turned on, since the 1 counts the small current detection range P ₁ in life accumulation, each time life counter CNTe counts up one. Normally open contacts x ₆ of the relay X ₆ responsive to the current detection of the medium current detection range P ₂ is connected is connected to the input terminal of the flip-flop FF1 to the power source E. Therefore, when the normally open contact x ₆ is turned on, the flip-flop F
The output terminal of F1 becomes high, and the clock Cr1 outputs a clock pulse to the counter CA1. When the number of clock pulses reaches a predetermined count, in this case three, the counter CA1 inputs a counter-up signal to the reset terminal of the flip-flop FF1, whereby the output terminal of the flip-flop FF1 becomes low and the output of the clock Cr1 becomes low. Stop. During this time, the same number of pulse signals as the number of clock pulses are input to the counter CNTe and counted. Relay X ₇ which responds similarly to the current detection of the large current detection range P ₃
Normally open contact x _7's are connected is connected to the input terminal of the flip-flop FF2 to the power source E. Therefore, when the normally open contact x ₇ is turned on, the output terminal of the flip-flop FF2 becomes high, the clock Cr2 outputs a clock pulse to the counter CA2. When the number of clock pulses reaches a predetermined count, in this case 10, the counter CA
2 inputs the counter-up signal to the reset terminal of the flip-flop FF1, and thereby the flip-flop FF1
Is output low, and the output of the clock Cr2 is stopped. During this time, the same number of pulses as the number of clock pulses are input to the counter CNTe and counted.

The life accumulating counter circuit B4 counts the number of pulses generated by the pulse generator PU, and is constituted by a counter CNTe common to each current detection range.
As described above, when the count number reaches 100 in any of the current detection ranges, it indicates that the life has expired.

In the above configuration, the relays Lr1 to Lr
n and Lrs are, for example, mechanical types such as reed relays, counters CNT1 to CNTn, CNTd, CNT
For e, for example, a mechanical addition type or subtraction type, for example, an electromagnetic counter is used.

FIG. 4 shows another embodiment in which a microcomputer is used for the control means CON instead of the relay circuit RL and the pulse generator PU. Relay circuit RL
Is a relay Lr corresponding to the current detection range.
A plurality of processes for determining whether or not the contacts Lrr1 to Lrrn of 1 to Lrn have been operated in descending order of the current detection range, and when it is determined that the plurality of processes have been operated, the processes correspond to the current detection ranges of each process. Counter circuit CN
Operating T1 to CNT3. FIG. 3B shows a flowchart. First, step S
In step 1, it is determined whether or not there is an input of the auxiliary contact aux.
If YES, the determination in step S1 is repeated. If YES, it is determined in step S2 whether or not the relay contact Lrr3 is ON. At the same time, a count for the number of operations is performed in step S2 ', and the data is stored in a memory such as an EEPROM in step S5. Write to. If NO in step S2, it is determined in step S3 whether or not the relay contact Lrr2 is ON.
If NO, it is determined in step S4 whether or not the relay contact Lrr1 is ON.
5 is written to a memory such as an EEPROM. Next, if YES is determined in the step S2, the counter CN is determined in a step S6.
The number of interruptions in the large current detection range is counted by T3, counted by a life accumulating counter CNTe in step S7, and data is written to a memory such as an EEPROM in step S5. If YES in step S3, the number of cuts in the middle current detection range is counted by the counter CNT2 in step S8, and counted by the life accumulation counter CNTe in step S9.
In step 5, data is written to a memory such as an EEPROM. If "YES" in the step S4, the number of cuts in the small current detection range is counted by the counter CNT1 in a step S10, the counting is performed by a life accumulating counter CNTe in a step S11, and the data is EEP in a step S5.
Write to a memory such as a ROM.

The counters CNT1 to CNTn, CN
Td and CNTe can be LED displays of, for example, 7 segments or the like, or the count value of the counter may be displayed on the display. Step S7
Output count number is 10 times for one input in step S9.
Is one input three times in step S11.
In the above, each output count is set to one input, but the present invention is not limited to this. Alternatively, each input may be set to one input, and each maximum life count may be individually determined.

[0035] According to these embodiments, even when operating all relay Lr1~Lrn is for the following current detection range P ₁ to P ₃ that contains the breaking current by the current detection circuit A,
Since only the counters CNT1 to CNTn corresponding to the current detection range including the breaking current are operated by the control means CON, the number of times of breaking is clear for each current detection range of the breaking current, and the remaining contact life of the breaker is clearly determined. can do.

Also, a pulse having a cumulative life number corresponding to each of the current detection ranges P _{1 to} P ₃ is generated for each interruption of the electric circuit, and by counting the number of pulses, the cumulative value of the breaking current according to the life curve is calculated. It is possible to determine whether or not a predetermined number of lifetimes has been reached for all the current detection ranges, whereby the remaining life can be clearly determined.

Furthermore, even if the logic circuit or the semiconductor portion of the microcomputer is damaged by the intrusion of surge or the like,
Since the relay, the relay circuit, and the counter are mechanical, the counter circuit required for determining the remaining life is operable, and therefore has surge resistance. The use of a microcomputer enables communication with a higher-level system.

When the pulse generator PU is constituted by a computer such as a microcomputer, the contacts Lrr1 to Lrrn of the relays Lr1 to Lrn are connected to the input of the microcomputer, and the pulse generator PU is connected in parallel with the relay circuit RL. Alternatively, the same processing as the relay circuit RL may be performed by a microcomputer, the count number may be stored in a memory, and transmitted to an upper system.

Further, each current detection range of the breaking current is determined by the resistance R
The number can be set by a combination of 1 to Rn. At this time, the division number n (n = 3 in the above example) of each current detection range is determined by the number of current ranges to be detected.

Further, the current detecting circuit A detects the short-circuit breaking current for two phases of the three-phase circuit, but may detect the short-circuit breaking current for three phases, for example.

Further, the cumulative breaking current counter of the present invention may be constituted by a current detecting circuit A, a control means CON, and a counter circuit B. Further, the cumulative cut-off current counter of the present invention comprises a current detection circuit A and a control means CON.
And a life accumulating counter circuit B4, and the counter circuit B may be omitted. Note that the current detection circuit A in this case is not limited to the above-described embodiment, and may be any circuit that detects a cutoff current in a plurality of current detection ranges.

Further, in the present invention, the above-mentioned cumulative breaking current counter may be built in a breaker.

[0043]

According to the first aspect of the present invention, even if all of the relays corresponding to the current detection range below the cut-off current included in the current detection circuit operate, the cut-off current is included in the control circuit. Since only the counter corresponding to the current detection range operates, the number of interruptions for each current detection range of the interruption current becomes clear, and the remaining contact life of the circuit breaker can be clearly determined.

According to the cumulative interruption current counter of the second aspect, the same effect as that of the first aspect is obtained.

According to the cumulative interruption current counter of the third aspect, the same effect as that of the first aspect is obtained.

According to the cumulative breaking current counter of the present invention, the cumulative value of the breaking current according to the life curve based on the count value of the life accumulating counter reaches a predetermined number of life times in all the current detection ranges. Can be determined
Thereby, the remaining life can be clearly determined.

According to the cumulative interruption current counter according to the fifth aspect, the same effects as those of the first and second aspects are obtained.

According to the cumulative cut-off current counter of the sixth aspect, in addition to the same effects as those of the third aspect, even if the logic circuit or the semiconductor portion of the microcomputer is damaged due to the intrusion of a surge or the like, the relay, the control circuit and the Since the counter is mechanical, the counter circuit required for determining the remaining life is operable and thus has surge resistance. The use of a microcomputer enables communication with a higher-level system.

According to the circuit breaker of the seventh aspect, the same effect as that of the first, second, third or fourth aspect is obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of one embodiment of the present invention.

FIG. 2 is a detailed diagram of a control circuit.

FIG. 3 is a life curve showing the number of interruptions with respect to an interruption current.

FIG. 4 shows a configuration of a control circuit according to another embodiment;
(A) is a block diagram, (b) is a flowchart.

FIG. 5 is a circuit diagram of a conventional example.

[Explanation of symbols]

 A current detection circuit B counter circuit RL relay circuit Lr1 to lrn relay PU pulse generator B3 operation counter circuit B4 life accumulation counter circuit CON control means P1 to P3 current detection range

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G035 AA15 AB08 AC13 AC19 AD04 AD10 AD13 AD19 AD25 AD28 AD29 AD49 AD58 5G030 XX16 XX18 5G058 BB05 BC05 BC16 BD10 BD14 CC01

Claims (7)

[Claims] A current detection circuit having a detection relay corresponding to a plurality of current detection ranges, wherein all of the relays below the current detection range including a cutoff current to be detected operate; A plurality of counter circuits provided corresponding to the current detection range; and the counter corresponding to the current detection range including the interruption current in response to the relay operating in the current detection range including the interruption current. A cumulative breaking current counter including control means for operating the circuit. 2. The control means according to claim 1, wherein each of the contacts associated with each of the relays is connected in series in order from a maximum to a minimum of the current detection range, and a power supply is connected to the maximum contact. The contact of the relay corresponding to the minimum current detection range is configured by a normally open contact and the counter circuit corresponding to the minimum current detection range is connected, and the other contacts are configured by switching contacts. 2. The cumulative cut-off current counter according to claim 1, wherein the normally closed sides are connected in series with each other, and the counter circuits of the corresponding current detection ranges are respectively connected to the normally open sides. 3. The control means is constituted by a microcomputer, and performs a plurality of steps of determining whether or not a contact point of the relay corresponding to the current detection range has been operated in descending order of the current detection range. And operating the counter circuit corresponding to the current detection range of each of the steps when it is determined that the current operation has been performed in a plurality of steps. 4. A current detection circuit for detecting a breaking current by dividing into a plurality of current detection ranges, and determining a cumulative number of lifespans for each of the plurality of current detection ranges in accordance with a life curve of the circuit breaker. A pulse generator that generates a pulse of the cumulative life number corresponding to the current detection range in response to a detection operation of the current detection range including the cutoff current; A cumulative cut-off current counter including a life-accumulating counter circuit for counting. 5. A current detection circuit having a relay for detection corresponding to a plurality of current detection ranges, wherein all of the relays below the current detection range including a cutoff current to be detected operate, and the plurality of current detection circuits; A plurality of counter circuits provided corresponding to the current detection range; and the counter corresponding to the current detection range including the interruption current in response to the relay operating in the current detection range including the interruption current. Control means for operating a circuit; and a lifespan cumulative number per interruption count for each of the plurality of current detection ranges is predetermined according to a life curve of the circuit breaker, and the circuit operates in the current detection range including the interruption current. A pulse generator for generating, in response to the relay, the pulse having the cumulative life number corresponding to the current detection range; and counting the number of pulses generated by the pulse generator. Cumulative breaking current counter and a counter circuit for lifetime cumulative for bets. 6. The cumulative interruption current counter according to claim 3, wherein said relay, said control means and said counter circuit are of a mechanical type, and said pulse generator is constituted by a logic circuit or a microcomputer. 7. A circuit breaker having the cumulative breaking current counter according to claim 1, 2, 3, or 4.