JPS5827742B2 - Denkiriyoukanshisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electricity quantity monitoring device in a power distribution system where one trunk line is branched into a plurality of branch lines. This is an electrical quantity monitoring device that targets temporary or low-priority load branch lines, and its purpose is to detect the cause of overcurrent even if the main line or branch branch line is used in a way that causes an overcurrent. Since only the branch line that has been disconnected is cut off, there is no inconvenience of damaging electrical equipment used on other branch lines, and since the cut-off is automatically restored, all you have to do is turn off the electrical equipment that caused the problem. Even if the cause of the cut-off occurs and you are unable to remove it due to other commitments, the cut-off state will be maintained after a predetermined period of time, so there is no need to worry about electricity quantity monitoring. The goal is to provide equipment.

Hereinafter, the configuration and the like will be explained in detail with reference to the illustrated embodiments.

The figure is a block diagram showing one embodiment of the present invention, and shows only the parts necessary for explanation.

In this figure, 1 is a mains current limiter connected to the mains 2, 4 is a mains current transformer also connected to the mains 2, and 3a
, 3b are branch lines branched from the main line 2, and electrical equipment (not shown) is connected to each branch line 3a + 3b.

Reference numeral 5 denotes a mains current detector connected to the mains current transformer 4, which can set an arbitrary reference current value, compares this set current value with the current value of mains 2, and outputs an output when the current value exceeds the set value. It is.

Reference numeral 6 denotes a first memory device that outputs an output based on the output of the mains current detector 5, and the output of the first memory device 6 is configured to continuously output an output unless a reset input is received.

7 is a first storage device 6 and a third storage device 18a, which will be described later.

A logical sum circuit (hereinafter referred to as an OR circuit) which receives the respective outputs of the circuits (181) and 181) as inputs.

Reference numeral 8 denotes a delay circuit which starts operating according to the output of the first memory 6 and outputs the output after an arbitrary set time; 9 an alarm which operates according to the output of the OR circuit 7; 10a and 10b the respective branch lines 3a and 3b. is a branch line current transformer connected to the

11a and 11b are first branch line current detectors connected to the branch line current transformers gK10a and 10b, respectively, which detect the presence or absence of current in the branch line 3a, 31) and send out a continuous output;
2a, 12b are first branch line current detectors 11a, 1
This is an energization indicator that indicates energization based on the output from 1b.

13a and 13b are first branch line current detectors 11a+11b
This second memory device 13a+13b is configured to be flip-flopped from edge 1 to edge 1, for example.

1 4 a t 1 4 b is the second storage device 13a+1
3b and the output of the delay circuit 8, the AND circuit (hereinafter referred to as A
．． (referred to as ND circuit), 15a and 15b are AND
Outputs from circuits 14a and 14b and counter 23a
OR with each output of y 2 3 b as input
The circuit 16a+16b is this OR circuit 15a.

The circuit breakers 16a and 16b are operated by the output from the branch line 3a. 3b, respectively.

1 7 a + 1 7 1) is the branch current transformer 1 0 a
An arbitrary reference current value can be set with the second branch line current detector connected to each branch line 3a + 3b, and this set current value is compared with the current value of branch line 3a + 3b to determine whether the current value is higher than the set value. It is configured to emit an output when .

18a, 18b are second branch line current detectors 17a, 17
a third memory device, 19, which stores and emits an output according to the output of b;
a, 191] are delay circuits that start operating according to the outputs from the third memories 18a and 18b and output after an arbitrary set time, and 20 are AND circuits 14a and 14b and delay circuits 19a and 19b, respectively. The OR circuit 21 receives the output of the OR circuit 20 as an input, and is a timer that creates an arbitrarily set time until automatic recovery using the output of the OR circuit 20, and resets the first memory 6 and the third memory 18a, 18b. Configured to produce input.

2 2 a + 2 2 b is A. N I) Circuit 14
a. 14b output and delay circuit 1 9 a + 1 9
an AND circuit (hereinafter referred to as an AND circuit) 23a which receives the output from the timer 21 and the output from the timer 21, performs a logical product of these inputs, and sends out a matching output;

231) is a counter that counts the number of outputs from the A N i) circuits 22a and 22b and outputs a certain output when a predetermined number of outputs is received, and the outputs are each output from the OR circuit 15a + 15b. via circuit breaker 16a.

16b.

Next, the operation of the embodiment shown in this figure will be explained.

Now, the contract current value is set to 301:A), and the reference current value of the mains current detector 5 is set to 30 (A).

Then, the wiring capacity of branch lines 3a and 3b is 20
(A.:l, second branch line current detector 1 7 a
, 1 7 b are set to 2 0 (A).

First, when a device is connected to each branch branch line 3a + 3b, a current flows through the branch branch line 3a,
The energization indicator 12a is detected by the output of the first branch current detector 11a.
performs an energization indication, and also generates an output from the second memory 13a, which becomes an input to the A-ND circuit 14a.

On the other hand, the output of the first branch line current detector 11b resets the second memory device 13b of the other branch line 3b, and the output from these memory devices disappears.

This operation always remembers the last connected branch line.

If the total operating current of devices connected to one branch branch line, for example, branch branch line 3a, exceeds 20 [A], the second
An output is generated from the branch line current detector 17a, and the third memory 18a is set and output is generated.

The output from the third memory 18a enters the OR circuit 7 and alerts the alarm 9.

Further, the output from the third memory 18a is output from the delay circuit 19a.
An output is generated after an arbitrary time delay, and circuit breaker 16a is operated through OR circuit 15a.

Furthermore, when the total operating current of devices connected to each branch branch line (for example, branch branch line 31) exceeds 30 (A), the main current detector 5 outputs an output, and the first memory 6 is set. The output passes through an OR circuit 7 and operates an alarm device 9.

At the same time, the output of the first memory 6 is delayed by an arbitrary time in the delay circuit 8, and is outputted, and becomes the input of the ANI) circuit 14b.

This causes the circuit breaker 16b of the branch line to which the last device was connected to be disconnected through the OR circuit 15b.

Therefore, the user must check the energization display 12 a! of the energization display panel installed in the housekeeping room, etc. 121) and remove it from devices that can be removed to keep it within the contract current (reference current) value.

Then, at the same time as the cutoff, the outputs of the delay circuits 19a+19b and the AND circuits 14a and 14b (for example, the output of the AND circuit 141) are input to the OR circuit 20, and the output starts operating the timer 21. After a set time, the output from the timer 21 resets the first and third memory 6.18a + 18b, and it also resets the ANI) circuit 22a.

22b.

Then, the output from the first memory 6 disappears, and A,
The output of the ND circuit disappears.

Therefore, the cutoff circuit is automatically restored. If the current exceeds the reference current value and is left unattended, the circuit breaker of the branch line, for example, the circuit breaker 16b, repeats breaking and returning.

This is because when the circuit breaker 16b is re-closed, the reference current value exceeds 30 (A) again, so the output of the main current detector 5 is generated and the output is sent to the cell 1 of the first memory 6. are delay circuit 8, AND circuit 14b, and OR circuit 1
The circuit breaker 16b is operated via the branch line 5b to cut off the input from the branch line 3b.

Then, when repeating the cutoff and return, the timer 21
The output becomes the output of the A, ND circuit 22b, which is counted by the counter 23b, and after reaching an arbitrarily set count value, an input is sent to the OR circuit 15b to prevent automatic recovery.

In addition, in order to reset the circuit breaker 16b, the counter 23
This can be done by adding a reset signal to b.

As is clear from the above description, the present invention is capable of issuing an alarm in the event of an overcurrent in the main line or overcurrent in a branch branch line in a power distribution system where one main line branches into multiple lines, and in case the former main line is overcurrent. In this case, only the last branch line that caused the overcurrent is cut off, and even if any of the latter branch lines becomes overcurrent, only that branch line is cut off, and it is automatically restored after a set predetermined time. In addition, the system is designed to prevent automatic recovery after the number of repetitions of interruption and automatic recovery reaches a set limit, so even if the main line or branch line is used in a way that causes overcurrent. Since only the branch line that caused the problem is cut off, there is no inconvenience of stopping the electrical equipment used on other branch lines, and since the cut-off is automatically restored, the electrical equipment that caused the problem can be turned off. Even if the cause of the shut-off occurs again and you are unable to remove it because you are busy with other tasks, there is no need to worry as the shut-off state will be maintained after a predetermined period of time. It is.

As described above, the present invention has many effects and is unique as an electricity quantity monitoring device in a power distribution system where one trunk line is branched into a plurality of lines.

[Brief explanation of the drawing]

The figure is a block diagram showing one embodiment of the present invention. 2...Main line, 3a, 3b...Branch branch line, 5...Main current detector, 6...First memory, 9... ...alarm, 10 a, 10
b... Branch current transformer, 11a. 11b...First branch current detector, 12a, 1
2b... Energization indicator, 13a, 13b...
...Second storage device, 14a, 14b, 22a, 2
2b-4NI) circuit, l6a, 16b"--breaker, 17a, 1zb...second branch current detector, 18a, 18b...third memory, 2
1... Timer 23a, 23b...
·counter.

Claims (1)

[Claims] 1 In a power distribution system where one main line is branched into multiple branch lines, there is a main current detector installed on the main line that outputs an output when the main current exceeds a set value, and an output based on the output of this main current detector. a first memory device that issues an alarm, and an alarm device that issues an alarm based on the output of the first memory device;
a plurality of first branch line current detectors that respectively detect the presence or absence of current in each of the branch branch lines and send out a continuous output; a energization indicator that is activated by the output of the first branch line current detector; a second memory device which is activated by one output of the branch line current detector and whose other output is sent to reset 1; and the logical product of the output of this second memory device and the output from the first memory device. a first AND circuit that outputs a coincidence output; a second branch line current detector that issues an output when the current flowing through each of the branch lines exceeds a predetermined value; and an output of the second branch line current detector. and a third memory device that outputs an output according to the above, and a third memory device that is connected to each of the branch lines, and operates to cut off when the respective outputs of the third memory device and the first AND circuit are generated, and operates to return when the output stops. and a timer that creates an arbitrarily set time until automatic recovery based on the output of the first AND circuit; and a timer that uses the output of this timer and the output of the first AND circuit as inputs, and performs a logical product of both of them to match. a counter that counts the number of outputs from the second AND circuit that outputs the output, and outputs a constant output when a predetermined number of outputs are received; and a third memory device is reset, and the counter counts the number of outputs of the timer, and when the count reaches a predetermined number of times, an output is generated and the circuit breaker is placed in a cut-off state. Electricity monitoring device.