JP5537779B2 - Current interrupt device - Google Patents

Description

  The present invention relates to a current interrupting device incorporated in an electric circuit for supplying current to a plurality of electric load facilities via a switch that interrupts the current when a load exceeding a set current value is applied.

At present, when the electric load equipment mainly used in factories is powered (three-phase 200V), the basic charge for each power is in addition to the actual amount of electricity used.
Further, the basic charge is determined by two types of contract methods: “load equipment contract” and “main switch contract” with an electric power company.

  In the “load equipment contract”, the sum of the maximum power (motor) capacity (KW) of all electric load equipment is defined as the contract capacity (KW), and the value obtained by multiplying the contract capacity by the unit price (yen) is the basic charge (yen ).

  The “main switch contract” is the contract capacity (KW) based on the current value actually flowing to the main switch in the factory when the electric load equipment is in operation, regardless of the power capacity of all the electric load equipment. The basic charge (yen) is obtained by multiplying the contracted capacity by the unit price (yen).

The unit price (yen) differs depending on each electric power company, but is basically the same for both the “load equipment contract” and the “main switch contract”.
In addition, the basic charge is actually subject to a power factor discount and consumption tax.

Basic charge (yen) = Contracted capacity (KW) x Unit price (yen) x 95% (power factor discount) x 1.05% (consumption tax)

It is calculated by the following formula.

The contract capacity of this "Main Switch Contract"

Contracted capacity (KW) = rated current of main switch (A) x voltage (200V) x 1.732 (coefficient) x power factor (100%) ÷ 1000

It is calculated by the following formula.

For example, when the basic charge for facilities with electrical load equipment shown in Table 1 below is calculated using the above formula, the basic charge for the “main switch contract” is the basic charge for the “load equipment contract”. It is about half that compared to, so it is effective in reducing the cost of electricity during factory operation.
In addition, 980 (yen) in the following calculation formula is an example of a unit price (yen) of a certain electric power company, and may vary depending on the electric power company.

In the “load equipment contract”, the total power capacity of the electrical load equipment in Table 1 is 34 KW, so the contract capacity is 34 KW, and this is applied to the above formula to calculate the basic charge.

34 (KW) x 980 (yen) x 95 (%) x 1.05 (%) = 33,236 yen

It becomes.

In the “Main switch contract”, the total current value of the electrical load equipment in Table 1 is 50A, so the minimum rated current value of the contracted main switch is 50A, and this value is used to calculate the contract capacity of the main switch. When calculated by applying to the formula,

50 (A) × 200 (V) × 1.732 (Coefficient) × 100 (%) ÷ 1000 = 17.32 (KW)

Since the decimal part is rounded down, the contract capacity is 17KW.
And when calculating the basic charge by applying this 17KW to the above formula,

17 (KW) x 980 (yen) x 95 (%) x 1.05 (%) = 16,618 yen

It becomes.

By the way, the basic charge of the “main switch contract” increases / decreases depending on the rated current value of the main switch as shown in the above calculation formula. It is necessary to change the rated current value of the main switch in proportion to the current value.
Basically, the rated current value of the main switch is set by operating all the electrical load equipment at its maximum capacity or by instantaneously flowing a current exceeding the rated current value when starting the power of the electrical load equipment. Therefore, the minimum rated current value of the main switch is equivalent to the total current value of the electrical load equipment so that the trip (state where the current is interrupted) is not caused.
In addition, the main switch is installed by selecting the instantaneous operation or the time delay operation for the purpose of detecting and removing the electric leakage accident. Usually, the main switch used in the factory suddenly In order to prevent trips and fires, those that operate for a while are used.

  As the switch that operates in a time-delayed manner, for example, time measurement is started at the same time when a current value (load) exceeding a set current value is applied, and when the preset time is reached, a current cut-off operation is performed, and the setting is performed. There is an electronically controlled switch in which time measurement is stopped and the time is reset to the value at the start of measurement when the load falls below a set current value before the set time. (For example, refer nonpatent literature 1).

In the switch described in Non-Patent Document 1, a current value (load) exceeding the rated current value (A) was applied to the switch as shown in the “Circuit Breaker Operation Table” attached to the catalog. At this time, the time until the shut-off operation is set for each magnitude of the current value, and when the set time is reached, the shut-off operation is performed, and further, the current exceeding the rated current value. If the rate of the value is in the range of 0 to 124% with respect to the rated current value, the blocking operation is not performed.
In other words, this switch does not trip for a set time even when a current value exceeding the rated current value is applied to the switch, so that there is little problem even if the current operation is not performed within that time. If the load facility is turned off, the load on the switch can be reduced, so that the trip of the switch can be prevented.
Therefore, when a current value exceeding the rated current value is applied to the switch, it is prevented from suddenly tripping, so there is no need to make a main switch contract with a minimum rated current value with a margin, It is possible to make the most of the merits of the “Main Switch Contract”, that is, to reduce the basic charge of electricity charges.
In addition, in the following Table 2, a part of the “breaker operation table for wiring” of the switch described in Non-Patent Document 1 is extracted and shown.

However, when the electronically controlled switch is used, when an overload is applied to the switch, it is necessary to manually disconnect the power source of any electrical load equipment within the set time. Therefore, if there is a certain amount of time until current interruption, such as “Overload 1” and “Overload 2” in Table 2, look for an electrical load facility that can be turned off with sufficient margin. Although the electric load equipment can be turned off, the time until current interruption is a short time of about several tens of seconds to several seconds as shown in “Overload 4” to “Overload 6” in Table 2. In some cases, because there is no time, there is a possibility that the power supply of the electrical load equipment cannot be cut off in time, or the power supply of the electrical load equipment that must continue to operate by mistake may be cut off.
In other words, if the electrical load equipment cannot be powered off in time, the switch trips and all electrical load equipment stops, and if the electrical load equipment that must continue to operate is turned off, the necessary work In addition, there is a risk that an accident may occur due to a sudden movement in the factory in order to cut off the power supply of the electrical load equipment.

NEO Co., Ltd. CPU control main switch built-in type power management device N-EB series catalog

  An object of the present invention is to prevent tripping of a time delay operation type switch when a load exceeding a rated current value is applied, and to continuously and efficiently operate an electric load facility. An object of the present invention is to provide a current interrupting device that solves the problem.

  In order to achieve the above object, a current interrupting device according to the present invention comprises at least the following configuration.

That is, the load size exceeding the rated current value is divided into a plurality of ranges, and the time until the current interrupting operation is set for each of the plurality of ranges, and when a load exceeding the rated current value is applied, the load Is a time delay operation type switch that performs a current interrupting operation after the lapse of a set time, and when the measured time reaches the set time, the current interrupting operation is performed and set If the load falls below the rated current value before the time, the time measurement is stopped, the time is reset to the value at the start of the measurement, and further, the current interruption operation is performed before the current interruption operation is performed. A current interrupting device incorporated in an electric circuit for supplying current to a plurality of electric load facilities via a switch having an alarm circuit for outputting current to an alarm means for alarming that,
The current interrupting device includes a first current interrupting device and a second current interrupting device, and the current interrupting operation of the other current interrupting device is performed more than the time until the current interrupting operation of one of these two current interrupting devices is performed. Set to take longer to do,
The first current interrupt device includes a control means for detecting a current from the alarm circuit and outputting the detection result,
The second current interrupt device includes a current value detecting means for detecting a current value in the electric circuit,
A current value detected by the current value detecting means, connected to the current value detecting means, and a control means for measuring the time during which the current flows and outputting the measurement result;
The control means of the first current interrupting device and the control means of the second current interrupting device may be one or more selected from the secondary side of the switch and the electrical load equipment. Connected in the electric wiring path, and cuts off the current for the electric load equipment and releases the current cut, and controls the current cut-off operation and the current cut-off release operation for the electric load equipment based on the output result of the control means. is connected to the connection means being,
The control means in the first current interrupt device is configured to control the connection means to perform a current interrupt operation when detecting a current from the alarm circuit, and from the alarm circuit from a state where the current is interrupted. When the current is no longer detected, the connection means is controlled to release the current interruption ,
The control means in the second current interrupting device includes control for determining whether the current value measured by the current value detecting means is included in any of the plurality of ranges, and the rated current value Before starting the measurement of the time during which the current flows when the load exceeds the load, and the time during which the current is flowing reaches the time for performing the current interrupting operation set in the determined range When the time reaches, the control for causing the connection means to cut off the current, the control for setting the time before the time for performing the current cut-off operation, and the current cut-off operation, current flows simultaneously. Control to reset the time to the value at the start of measurement, and simultaneously with or after the reset, the measurement of the time during which the current flows is started, and the connection means And stop the measurement of the time during which the current is flowing when the load becomes less than the rated current value before the time before the time to reach the time to perform the current interruption operation and the control to release the current interruption operation. together, and wherein the the control to reset the said time to a value of the time of measurement start line of TURMERIC.

By connecting a phase advance capacitor in the electrical wiring path on the secondary side of the switch when the delayed reactive power value caused by the load increase of the electrical load equipment exceeds a preset value, and a leading power factor state, leading reactive power generated by the leading power factor state, when it exceeds a preset value, and features that you have provided a power factor controller to cut off the connection of the phase advance capacitor To do.

As long as the switch referred to in the present invention is of a type that operates in a time-delayed manner, the type of the electronic control type illustrated in Non-Patent Document 1, the electromagnetic type, or the like is not limited.
In addition, the electrical load equipment referred to in the present invention includes all what is called three-phase (200V) power, for example, various machine tools such as NC lathes, NC milling machines, and lathes used in factories, air conditioners, etc. The various air-conditioning equipment, and various transport equipment such as conveyors and elevators can be exemplified.
Further, for the electrical load equipment connected to the connection means of the present invention, for example, one or a plurality of electrical load equipment that does not affect the production activity even if it is stopped is selected in the factory.

  According to the present invention, a current interruption capable of continuously and efficiently operating an electrical load facility by preventing tripping of a time delay operation type switch when a load exceeding a rated current value is applied. Equipment can be provided.

Hereinafter, the best mode for carrying out the current interrupting device A according to the present invention will be described with reference to the drawings.
1 to 3, a schematic electrical circuit diagram showing a current cutoff device A according to the present invention, FIG. 4, FIG. 5 is a flowchart showing the operation of the current interrupting device A.
The current interrupt device A includes a first current interrupt device D and a second current interrupt device E.

  As shown in FIGS. 1 to 3, the electric circuit exemplified in this embodiment includes a power supply V (three-phase 200 v) on the primary side to a plurality (five in the drawing) of electric load equipment M1 to M5 on the secondary side. A well-known switch 2 having a built-in watt-hour meter 1, a current transformer B1 that constitutes a part of a power factor control device B, which will be described later, and an ELB (leakage breaker) in order from the primary side to the secondary side in the wiring path. A main switch (switch) 3 that is operated by electronic control for a time delay is connected.

  In the following, in FIGS. 1 to 2, the wiring through which current flows is shown as a solid line, and the wiring through which no current flows is shown as a broken line.

  The main switch 3 according to this embodiment divides a load exceeding the rated current value into a plurality of ranges, and sets a time until the current interruption operation for each of the plurality of ranges, and a load exceeding the rated current value is applied. Sometimes a time delay operation type switch that performs a current interrupting operation after the lapse of a time set in a range including the load, and performs a current interrupting operation when the measured time reaches a set time. If the load falls below the rated current value before the set time, the time measurement is stopped, the time is reset to the value at the start of measurement, and before the current interrupting operation is performed, the current It is a well-known one having an alarm circuit P that outputs a current to an alarm means C that alarms that a shut-off operation is performed.

  The alarm circuit P is, for example, a switch circuit as shown in FIG. 5, and a detection means P1 for detecting a current value flowing through the main switch 3, and a current value detected by the detection means P1 indicates a low current value. A switch P2 that is turned on by the detection means P1, and a power supply P3 that turns the switch P2 on and off and supplies power to the circuit in the ON state. .

This alarm circuit P turns on the switch P2 to supply power from the power source P3 into the circuit when the detection means P1 detects a current value exceeding the low current value, and the detection means P1 is low. When a current value less than the current value is detected, the switch P2 is turned off and the supply of power from the power source P3 is stopped.
That is, when the switch P2 is ON, a current is output to the current interrupt device A and the alarm means C, and when the switch P2 is OFF, current is output to the current interrupt device A and the alarm means C. Is not output.
The timing for turning on the switch P2 of the alarm circuit P can be arbitrarily set, for example, several seconds to several tens of seconds before the time when the current of the main switch 3 is cut off (see Table 2).

The current interrupt device D is connected to the alarm circuit P, and interrupts the current flowing through the charge load facility M5 when the current output from the alarm circuit P is detected .
As shown in FIGS. 1 to 3, the current interrupt device A includes a control means A ′ having a current relay A1 and a timer A2, and an electromagnetic contactor A3 which is an example of a connection means. It is connected to the timer A2, and the electromagnetic contactor A3 is connected to the timer A2.

Basically, when the current output from the alarm circuit P is detected, the control means A ′ controls the electromagnetic contactor A3 so as to release the current interruption and maintain the current interruption release state.
The electromagnetic contactor A3 is connected in a wiring path extending from the secondary side of the main switch 3 to the electric load facility M5, and based on the control of the control means A ′, interrupts the current to the electric load facility M5. , And canceling the current interruption.

Here, the operation of the control means A ′ will be described. When the current relay A1 detects the current output from the alarm circuit P, the electromagnetic contactor A3 cuts off the current to the electric load equipment M5 from the electromagnetic contactor A3 ( Current interruption).
The alarm circuit current is not output P, the current relay A1 does not detect the output current, electric release to (current interruption releasing) the interruption of current in the magnetic contactor A3 is the electrical load equipment M5.
The timer A2 is for setting the electric load equipment M5 from the current interruption state to the current interruption release state after a certain period of time, and setting the time from 0 second to an arbitrary interruption. You can set up to seconds.
When the time of the timer 2 is set to 0 seconds, the electric load equipment M5 can be immediately returned from the current interruption state to the current interruption release state.

The power factor control device B is for always controlling the power factor in the circuit to an optimum one, and when the power factor is a lagging power factor, the charge (electric energy) of the phase advance capacitor B2 is a circuit. To be put in.
Basically, the power factor control device B is configured to charge the phase shift capacitor from the phase advance capacitor when the circuit is in a delayed power factor state due to the delayed reactive power in an electrical circuit using an electrical load facility that generates delayed reactive power. A well-known device can be used in which the power factor is efficiently used by canceling the delay power factor with the leading power factor generated by applying (electrical energy).

As shown in FIG. 3, the power factor control device B of this embodiment is configured such that the current transformer B <b> 1, the current relay B <b> 3, the electromagnetic contactor B <b> 4, and the phase advance capacitor B <b> 2 are the primary side (current transformer). A4 side) is connected in order from the secondary side (electric load equipment M1 to M4 side).
The electromagnetic contactor B4 is connected in a wiring path extending from the secondary side of the main switch 3 to the phase advance capacitor B2.
In this embodiment, the current value detected by the current transformer B1 is converted into a power factor, and when the current relay B3 measures that the power factor is equal to or less than a predetermined power factor, the current relay B3 determines that the circuit is in a delayed power factor state, and the secondary side of the main switch 3 and the phase advance capacitor B2 are connected to the electromagnetic contactor B4 (see FIG. 3). To output.
When the current relay B3 measures that the power factor is equal to or greater than the set power factor to 100%, the current relay B3 determines that the delayed power factor state in the circuit has been released, and the electromagnetic contactor. Output is performed so that the secondary side of the main switch 3 and the phase advance capacitor B2 are not connected to B4 (see FIG. 1).
That is, when the circuit is in a delayed power factor state, the power factor in the circuit can always be kept optimal by automatically charging the phase advance capacitor B2 into the circuit.
The set constant power factor is preferably 95% or more at which a power factor discount is set in the electricity bill.

By arranging the power factor control device B of this embodiment, the rated current value of the main switch 3 can be lowered as follows.
For example, when the electric load equipment M1 to M5 has a delay power factor of 75%, when the current value of the electric load equipment M1 to M5 is 40A, actually, 10A which is 25% of the 40A. Since the minute becomes reactive power and 30A becomes active power, the rated current value of the main switch 3 can be set to 30A.
That is, as described above, the basic charge of the “main switch contract” increases and decreases depending on the rated current value of the main switch. Therefore, if the rated current value of the main switch 3 can be reduced by 10 A, the basic charge is increased accordingly. Charges can be reduced.
In addition to the reduction of the basic charge by the current interrupting device A, the basic charge can be reduced by the power factor control device B, so that a more economical electric circuit can be obtained.

The alarm means C is connected to the alarm circuit P, and based on the current output from the alarm circuit P, an alarm for notifying the operator that a load exceeding the rated current value is applied to the main switch 3. Means .
As the alarm means C, a known device that performs an alarm operation can be used from the viewpoint of alarming each worker when current is output from the alarm circuit P.
Incidentally, the alarm means C of this embodiment includes a current relay C1 connected to the primary side of the current relay A1 of the current interrupting device A, a rotating lamp C2 connected to the current relay C1, and a buzzer C3.

Based on the current output from the alarm circuit P, the current relay C1 of the present embodiment is configured to output the rotary lamp C2 and the buzzer C3 to operate (not shown).
Further, when the output of the current from the alarm circuit P stops, the current relay C1 outputs so as to stop the operation of the rotating lamp C2 and the buzzer C3 (see FIG. 1).
That is, when the current in the circuit is overloaded, the worker knows the current load state in the circuit based on this alarm by giving a visual and audible alarm to the worker. be able to.
If the worker can know the current load state in the circuit, for example, when the worker tries to operate a new electric load facility, the worker can wait until the overload state is released. it can.

Hereinafter, a specific operation of the current interrupt device D of the present embodiment will be described based on the electric circuit diagrams of FIGS. 1 to 3 and the flowchart of FIG. 4 .

First, Table 3 shows conditions for the current interrupt device D to interrupt the current to the electrical load equipment M5.
In the table, the load factor indicates the rate of the current value exceeding this when the rated current value of the main switch 3 is 100%.
In the table, A indicates the time for which the switch P2 of the alarm circuit P is turned ON, and B indicates the time until the main switch 3 performs the current interruption operation.

For the detection means P1 in the alarm circuit P, the load factor exceeding the rated current value shown in Table 3 is set in the same range and in the same number as the load factor set in the main switch 3, and the set load factor is set. Is set to operate the switch P2 in the ON state in a time shorter than the time set in the main switch 3 (Table 3B column).
In this embodiment, the detection means P1 turns off the switch P2 until the load factor is 124%, and the switch P2 is turned on when the load factor exceeds this.
Also, the time shown in Table 3A for the detection means P1 to turn on the switch P2 is an example in the present invention, and this time can be arbitrarily set for the detection means P1.
Further, the electrical load equipment M5 controlled by the current interrupting device A has a capacity that is equal to or less than the rated current value of the main switch 3 or the load factor of No. 1 shown in Table 3 when the current is interrupted. For example, a device that does not have a problem even if it is not operating in a factory or the like is selected.
Further, in this embodiment, the electric load equipment that is controlled to cut off the current by the current cut-off device D is illustrated as one, but this may be two or more, such as the rated current value of the main switch, the factory, etc. In consideration of things that do not have any problems even if they are not in operation.

Next, operation | movement of the electric current interruption apparatus D is demonstrated based on the flowchart of FIG.
When the electric load equipment M1 to M5 is activated, detection of the value of the current flowing through the main switch 3 of the detection means P1 is started (step S1).
It is determined whether or not the detected current value exceeds the load factor indicated by numbers 2 to 6 in Table 3B (steps S2 to S6).
When the determination result exceeds the load factor shown in the numbers 2 to 6 in the column 3B, the measurement is started until any time in the numbers 2 to 6 in the column 3A corresponding to the load factor. (Step S7).

  If the current value becomes a load factor equal to or lower than number 1 in Table 3B during this time measurement (step S8), the time measurement in step S3 is stopped (step S9), and the measured time is measured at the start of measurement. To the initial value (step S10).

When the time measured in step S3 reaches one of the numbers 2 to 6 in the column 3A corresponding to the load factor applied to the main switch 3 (step S11), the detection means P1 turns on the switch P2. The state is set (step S12).
When the switch P2 is turned on, a current flows in the alarm circuit P, and this current is output to the current relay A1 and the alarm means C (step S13).
When the current is output, the current relay A1 sets the electromagnetic contactor A3 in the current interruption state (step S14), and the current relay C1 operates the rotating lamp C2 and the buzzer C3 (step S15).
At this time, the operation of the electrical load equipment M5 is stopped because the magnetic contactor A3 is in a current interruption state (see FIG. 2).
Then, when the operation of the electric load equipment M5 is stopped, the total current value of the electric load equipment M1 to M4 in operation is equal to or less than the rated current value of the main switch 3, or the load of No. 1 shown in the column of Table 3A. Since it becomes less than the rate, the main switch 3 will not trip even if the set time (Table 3B column) elapses.
Furthermore, it is measured when the total current value of the operating electrical load equipment M1 to M4 is less than the rated current value of the main switch 3 or less than the load factor of No. 1 shown in the Table 3A column (step S16). The measured time is reset to the value at the start of measurement (initial state) (step S17), and after the reset, whether or not the load factor is 125% or more of the rated current value is measured from the initial state in step S2. .

When the total current value of the operating electrical load equipment M1 to M4 is less than the rated current value of the main switch 3 or less than the load factor of No. 1 shown in the Table 3A column, the detection means P1 turns off the switch P2. Then, the output of current from the alarm circuit P is stopped (step S18).
When the output of current from the alarm circuit P is stopped, the current relay C1 stops the operation of the rotating lamp C2 and the buzzer C3 (step S19), and the timer A2 starts measuring the set time (step S20). .
When the time measured by the timer A2 reaches the set time (step S21), the current relay A1 releases the current interruption state for the electromagnetic contactor A3 (step S22).
At this time, the operation of the electrical load equipment M5 is resumed because the electromagnetic contactor A3 is in a current interruption release state (see FIG. 2).
And the operation | movement from step S1 is repeated again until all the operation | movement of the electrical load equipment M1-M5 is stopped.

According to the setting of the timer A2 of this embodiment, a continuous overload is applied to the circuit by changing the current from the current interruption state of the magnetic contactor A3 to a current interruption release state after a certain time. Can be prevented.
Note that the electromagnetic contactor A3 may be immediately brought into the current interruption release state by setting the timer A2 to 0 seconds or disabling the timer A2.
Even with such a configuration, tripping of the main switch 3 can be prevented even when the current value of the electrical load equipment M1 to M5 becomes a load factor that exceeds the rated current value of the main switch 3.

The second current interrupting device E includes a current transformer A4 that detects a current value in the electric circuit, and when the current transformer A4 detects a load that exceeds the rated current value, a current that flows through the charge load facility M5. Is to shut off.

The second current interrupt device E is formed by connecting the current transformer A4 connected to the primary side of the main switch 3 to a current relay A 1 ′ of the control means A ″ having the same configuration as the current interrupt device D. .
The current transformer A4 constantly detects the current value in the electric circuit on the primary side of the main switch 3, and outputs the detected result to the current relay A1 ′ .
That is, the control of the control means A ″ in this embodiment is controlled so that the magnetic contactor A3 maintains the current interruption release state and the current interruption release state based on the current value measured by the current transformer A4. Is.
Further, this embodiment of the timer A2 'measures a time before the time to reach the cutoff operation time of the main switch 3, which is set for each size of the load (see Table 4B column), this time At the time of measurement, the electromagnetic contactor A3 is brought into a state of interrupting the current to the electric load facility M5.
Also, 'during time measurement, the current value detected by the current transformer A4 is, the current relay A 1 as the following load rated current' timer A2 when the measured, the timer A2 'is a time measurement At the same time, the timer A2 ' time is reset to the value at the start of measurement (initial state).
Further, after the current interruption of the magnetic contactor A3, the time of the timer A2 ' is reset to the value at the start of measurement.
Further, when the current value detected by the current transformer A4 is a load equal to or lower than the rated current value, the timer A2 ' does not operate, and the current interruption release state of the magnetic contactor A3 is maintained.

Hereinafter, a specific operation of the current interruption device E of this embodiment, the electrical circuit diagram of FIGS. 1-3, and will be described with reference to the flowchart of FIG.

First, Table 4 shows conditions for the current interrupt device E to interrupt the current to the electrical load equipment M5.
In the table, the load factor indicates the rate of the current value exceeding this when the rated current value of the main switch 3 is 100%.
In the table, A indicates the time until the current interrupting device E operates to interrupt the current to the electric load equipment M5, and B indicates the time until the main switch 3 performs the current interrupting operation.

In the control means A ″ , a load factor exceeding the rated current value shown in Table 4 is set in the same range and in the same number as the load factor set in the main switch 3, and the measurement corresponding to the set load factor is performed. time is set (Table 4 a column), the main switch 3 have been set time to work current interruption in a shorter time than (Table 4B column).
In this embodiment, the current interrupt device E does not operate up to a load factor of 124%, but operates when the load factor exceeds this.
Moreover, the time until the current interrupting device E interrupts the electric current to the electric load equipment M5 shown in Table 4A is an example in the present invention, and this time can be arbitrarily set for the control means A ″ .

Next, the operation of the current interrupting device E of this embodiment will be described with reference to the flowchart of FIG.
When the electric load facilities M1 to M5 are activated, the current transformer A4 starts detecting the current value (step S1).
At this time, the electromagnetic connector A4 is brought into a state in which a current is passed to the controlled electrical load equipment M5 (current interruption release state) by the control means A ″ , and the electrical load equipment M5 is in an operating state. (See FIG. 6).

It is measured whether or not the current value detected by the current transformer A4 is a load factor of 125% or more of the rated current value of the main switch 3 (step S2).
When the measured load factor is 125% or more, it is determined to which number shown in Table 3 the load factor is included (steps S3 to S7).
When the number is determined, the time measurement of the timer A2 ′ is started (step S8).

When the time in the A column corresponding to the determined number (the time set in the control means A ″ ) has elapsed (step S9), the time measurement of the timer A2 ′ is stopped (step S10), and the time is measured. The value is reset to the (initial state) value (step 11), and the electromagnetic contactor A3 is brought into a current interruption state (step S12).
At this time, the operation of the electrical load equipment M5 is stopped because the magnetic contactor A3 is in a current interruption state (see FIG. 2 ).
Then, when the operation of the electric load facility M5 is stopped, the total current value of the operating electric load facilities M1 to M4 is equal to or less than the rated current value of the main switch 3, or the load factor of No. 1 shown in Table 3 since the, does not trip even after the main switch 3 is set time (Table 4 B column).

In the present embodiment, the timer A2 ′ reset in the step S11 is caused to again measure time (step S13), and the time measurement of the timer A2 ′ is again stopped after an arbitrary time has elapsed (step S14) (step S14). with S15), it resets the time of the timer A2 'to the value of the measurement at the start (initial state) (step S16), and the electromagnetic contactor A3 to unblocking state of the current (step S17) (see FIG. 1) control To do.
Then, after the resetting, in step S2, whether or not the load factor is 125% or more of the rated current value is measured from the initial state.

That is, it is possible to prevent an overload from being continuously applied to the circuit by changing the current interruption state of the magnetic contactor A3 from the current interruption state to a state where the current interruption is released after a certain amount of time.
It should be noted that the electromagnetic contactor A3 may be immediately released from the current interruption state after the timer A2 ' is reset in the step S11. With such a configuration, the current values of the electric load equipments M1 to M5 are the main values. Even when the load factor exceeds the rated current value of the switch 3, the time measurement of the timer A 2 ′ is started from the initial state, so that the trip of the main switch 3 can be prevented.

If the load factor becomes less than 125% before the time elapses (step S18), the time measurement of the timer A2 ' is stopped (step S19) and the time of the timer A2 ' is started (initial state). The value is reset (step S20), and after the reset, measurement of whether or not the load factor is 125% or more of the rated current value is restarted from the initial state in step S2.

According to the above current interrupting devices D and E, when the rated current value of the main switch 3 is lower than the total current value of all the electric load facilities M1 to M5, the current values of the electric load facilities M1 to M5 However, even if the load factor exceeds the rated current value of the main switch 3, the current flowing through the electrical load equipment M5 can be automatically cut off before the time set in the main switch 3, The interrupted current can be supplied again to the electric load equipment M5.
Therefore, as described above, since the basic charge of the “main switch contract” increases and decreases depending on the rated current value of the main switch, the rated current value of the main switch 3 is set for all the electric load equipments M1 to M5. If the value is lower than the total current value, the basic charge can be reduced by that amount, and the tripping of the main switch 3 is prevented by the current interrupting device A, so the necessary electrical load equipment is stopped. It is possible to operate continuously without making it happen.

Second current blocking device E is for use as a backup of the first current blocking device D, even if the current interrupting device D used primarily not function in failure or the like, the current interrupting device E for backup it is possible to perform current cutoff control in, and is mainly when no operating current interrupting device D to be used, which allow automatically actuated current interrupt device E for backup and monitoring.

As a method for monitoring that the current interrupting device D does not operate , for example, a method using the current relay A1 ′ and the timer A2 ′ of the backup current interrupting device E can be cited.

In this embodiment, as shown in Table 5, the time during which the current interrupting device E performs the current interrupting operation (see Table 5B column) is longer than the time during which the current interrupting device D performs the current interrupting operation (see Table 5A column). If the current value detected by the current transformer A4 of the auxiliary device E does not decrease even when the current interrupting device D reaches the current interrupting operation time, the current interrupting device D is abnormal. The current interruption device E is judged to perform a current interruption operation.
The time setting shown in Table 5B can be set by setting the timer A2 ' of the current interrupting device E.
Therefore, even if the current interrupting device D stops operating due to a failure or the like, the current interrupting device E performs the current interrupting control, so that the trip of the main switch 3 can be reliably prevented.

In the present embodiment, a device using a first current cut-off device D as the main, have been exemplified as a device that uses the second current cut-off device E for backup, in the present invention, apparatus and a backup to be used primarily it may be the relationship between the device to be used for use Conversely, in any case, may be longer than the time unit to be used as a main time for interrupting device current used for backup to current interruption.
The time shown in Table 5A column and Table 5 B column is an example of the present invention, this time can be set arbitrarily.

It should be noted that the present invention is not limited to the illustrated embodiments, and can be implemented with configurations within a range that does not deviate from the contents described in the respective claims.
For example, in the present embodiment, the control means for controlling the operation of the electromagnetic contactor A3 is exemplified as a structure using the current relays A1, A1 ′ and the timers A2, A2 ′. For example, the control means using the CPU, that is, the CPU that controls the entire apparatus, the control program executed by the CPU, the current value, the load factor, the time, the current cutoff operation, the current cutoff ROM that stores various data such as release operation, RAM that temporarily stores various data such as current value, load factor, time, current interruption operation pattern, current interruption release operation pattern, and various input information and calculation results A timer for measuring various times, switches for performing various editing, a display for displaying various editing screens and various information, and various applications including the control program. Control means including a storage device for storing the emissions programs and various data, and the like.
Further, the power factor control device B and the alarm means C may be controlled by the control means using the CPU.

The electric circuit diagram to which the current interrupting device concerning the present invention is applied. The electric circuit diagram made into the electric current interruption state with respect to electrical load equipment. The electric circuit diagram of the state which injected the electric charge of a phase advance capacitor. The flowchart which shows operation | movement of a 1st electric current interruption apparatus. The flowchart which shows operation | movement of a 2nd electric current interruption apparatus. Alarm circuit diagram.

Explanation of symbols

A: Current interrupter A1: Current relay A2: Timer
A1 ': Current relay
A2 ': Timer A3: Electromagnetic contactor A4: Current transformer A': Control means
A ": Control means B: Power factor control device B2: Phase advance capacitor M1: Electric load equipment M2: Electric load equipment M3: Electric load equipment M4: Electric load equipment M5: Electric load equipment 3: Main switch (switch)
C: alarm means P: alarm circuit D: the first current blocking equipment E: first current blocking equipment

Claims (2)

The load size exceeding the rated current value is divided into multiple ranges, and the time until the current interruption operation is set for each of the multiple ranges, and the load is included when a load exceeding the rated current value is applied. This is a time-delayed type switch that performs a current interruption operation after the set time has elapsed, and performs a current interruption operation when the measured time reaches the set time. When the load falls below the rated current value, the time measurement is stopped, the time is reset to the value at the start of measurement, and the current interrupting operation is performed before the current interrupting operation is performed. A current interrupting device incorporated in an electric circuit for supplying current to a plurality of electric load facilities via a switch having an alarm circuit for outputting current to alarm means for alarming,
The current interrupting device includes a first current interrupting device and a second current interrupting device, and the current interrupting operation of the other current interrupting device is performed more than the time until the current interrupting operation of one of these two current interrupting devices is performed. Set to take longer to do,
The first current interrupt device includes a control means for detecting a current from the alarm circuit and outputting the detection result,
The second current interrupt device includes a current value detecting means for detecting a current value in the electric circuit,
A current value detected by the current value detecting means, connected to the current value detecting means, and a control means for measuring the time during which the current flows and outputting the measurement result;
The control means of the first current interrupting device and the control means of the second current interrupting device may be one or more selected from the secondary side of the switch and the electrical load equipment. Connected in the electric wiring path, and cuts off the current for the electric load equipment and releases the current cut, and controls the current cut-off operation and the current cut-off release operation for the electric load equipment based on the output result of the control means. is connected to the connection means being,
The control means in the first current interrupt device is configured to control the connection means to perform a current interrupt operation when detecting a current from the alarm circuit, and from the alarm circuit from a state where the current is interrupted. When the current is no longer detected, the connection means is controlled to release the current interruption ,
The control means in the second current interrupting device includes control for determining whether the current value measured by the current value detecting means is included in any of the plurality of ranges, and the rated current value Before starting the measurement of the time during which the current flows when the load exceeds the load, and the time during which the current is flowing reaches the time for performing the current interrupting operation set in the determined range When the time reaches, the control for causing the connection means to cut off the current, the control for setting the time before the time for performing the current cut-off operation, and the current cut-off operation, current flows simultaneously. Control to reset the time to the value at the start of measurement, and simultaneously with or after the reset, the measurement of the time during which the current flows is started, and the connection means And stop the measurement of the time during which the current is flowing when the load becomes less than the rated current value before the time before the time to reach the time to perform the current interruption operation and the control to release the current interruption operation. with current interrupting device comprising a a control for resetting the said time to a value of the time of measurement start line of TURMERIC. By connecting a phase advance capacitor in the electrical wiring path on the secondary side of the switch when the delayed reactive power value caused by the load increase of the electrical load equipment exceeds a preset value, and a leading power factor state, leading reactive power generated by the leading power factor state, when it exceeds a preset value, and features that you have provided a power factor controller to cut off the connection of the phase advance capacitor The current interrupting device according to claim 1.

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