JPH0543066B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a ground fault detection device, and particularly to an automatic ground fault detection device that automatically detects ground faults at a plurality of locations in a sequence circuit.

[Background of the invention]

Conventionally, as a method for detecting a ground fault point in a relay sequence circuit, for example,
There have been various proposals such as No. 146730 and Japanese Unexamined Patent Publication No. 59-208474, but all of them require time to measure the insulation resistance one by one, especially for circuits located in remote locations. This was a difficult task as a lot of time was spent in transportation.

In addition, in circuits located in places where condensation occurs, it is difficult to accurately grasp the ground fault status because it is not known when a ground fault will occur, and there is a possibility that the situation will be restored by the time the site arrives. I was getting used to it.

[Purpose of the invention]

An object of the present invention is to provide an automatic ground fault detection device that can quickly and automatically detect and record ground fault conditions at multiple locations in a sequence circuit.

[Summary of the Invention] The present invention is characterized in that it uses a ground fault detection device capable of detecting ground faults in a energized state to detect ground faults at multiple locations in a sequence circuit consisting of a plurality of relays. An input switching means is provided which is connected to a ground fault detection point and switches the detection point to be input to the ground fault detection device in accordance with a switching command, and controls this switching command and detects the ground fault from the output of the ground fault detection device at that time. By determining the fault location and recording the determination data, ground fault conditions at a plurality of locations can be automatically and quickly detected and recorded simply by controlling the switching.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a block diagram of an automatic ground fault detection device according to the present invention.

In the figure, an input switching device 1 selectively switches the detected location from the ground fault detection locations connected to the input terminals a to z to the ground fault detection device 2 according to a switching command from the input/output device 3. It is for input to. Note that the terminal Y _y is a terminal for connecting the (-) side power supply bus. The ground fault detection device 2 performs ground fault detection for each of the ground fault detection locations a to Z inputted from the input switching device 1 even in the energized state, and outputs the results to the input/output control device 3. This input/output control device 3 instructs the input switching device 1 to switch the ground fault detection location, and processes the output of the ground fault detection device 2 to determine the presence or absence and location of a ground fault. , outputs the data to the recording device 4 and records it.

In FIG. 2, ground fault detection is performed using the device shown in FIG. This is an example of a relay sequence circuit.

The figure shows a number of relays R _a to R _z excited by the DC power bus (+) (-), each with a normally open contact A _a
~ _Az and normally closed contacts Ba _{~ Bz} are connected in series. Here, these normally open contacts A _a
~ A _z and the operating conditions of the normally closed contacts B _a ~ B _z are not directly related to the present invention, so their explanation will be omitted, but for example,
When normally open contact A _a and normally closed contact B _a close, P _a −
Relay R _a is excited by the sequence circuit A _a −B _a −X _a −R _a −N _a . Other relays R _b ~ R _z
The same applies to .

In such a relay sequence circuit, for example, X _a to X _z are set as the ground fault detection points, and terminals a to X of the input switching device 1 in FIG.
Connect to z respectively. Also, connect the (-) side bus bar _Yz to the terminal _Yy .

In this state, it is assumed that a ground fault has occurred at the ground fault detection point X _y . The input switching device 1 sequentially switches input terminals a to z according to a command from the input/output control device 3.
The states of the ground fault detection points X _a to X _z are input to the ground fault detection device 2 . Therefore, the ground fault detection device 2 detects the ground fault detection point X a input from the input switching device 1 _.
Ground fault detection is performed sequentially in the order of ~ _Xz , and the detected data is output to the input/output control device 3. As a result, in the input/output control device 3, this ground fault detection data and the state of the input switching device 1, that is, since the ground fault detection data has occurred at the y terminal of the input switching device,
Determine that the ground fault location is X _y and store it.
At the same time, the recording device 4 records this determination result, that is, the ground fault location or terminal number, and also records the
Record the time of occurrence.

As described above, according to this embodiment, the input switching device 1 automatically switches the plurality of ground fault detection points X _a to X _z , and the output thereof is sent to the ground fault detection device 2 to detect the presence or absence of a ground fault. The input/output control device 3 processes the ground fault detection data and the switching command to the input switching device 1, stores the input terminal of the ground fault occurrence and the time of the ground fault occurrence, and records the ground fault detection data and the switching command to the input switching device 1.
can be recorded.

FIG. 3 is a block diagram showing another embodiment of the invention. In this example, since the detection time setting device 5 for setting the ground fault detection start time and end time is provided in the embodiment shown in FIG. Further, by providing an alarm device 6 that issues an alarm when a ground fault is detected, it is possible to detect only an alarm, and the amount of recording paper can be saved.

Furthermore, in the embodiments of FIGS. 1 and 3,
The input/output control device 3, the recording device 4, the detection time setting device 5, and the alarm device 6 are installed in a remote location other than the sequence circuit installation location shown in FIG. 2, and the input switching device 1 is installed using a telephone line or the like. By controlling the ground fault detection device 2 and configuring it to receive ground fault data from the ground fault detection device 2, it is possible to centrally detect ground faults in one place, even though many sequence circuits are scattered in various places. . Therefore, in this case, it becomes possible to instantly detect ground fault conditions in various locations.
There will be no time spent on transportation, which will greatly improve efficiency.

〔Effect of the invention〕

According to the present invention, it is possible to quickly and automatically detect and record ground fault conditions at a plurality of locations in a sequence circuit, and therefore it is possible to significantly improve the efficiency of ground fault detection work.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an automatic ground fault detection device according to the present invention, FIG. 2 is a circuit diagram showing an embodiment of a relay sequence circuit, and FIG. 3 is a block diagram showing an embodiment of an automatic ground fault detection device according to the present invention. FIG. 3 is a block diagram showing another embodiment. Explanation of symbols, a to z...Input terminals, R _a to R _z ...
...Relay, X _a to X _z ... Ground fault detection point.

Claims (1)

[Scope of Claims] 1. A sequence circuit comprising a plurality of relays and having a plurality of ground fault detection tubes, and a sequence circuit comprising a ground fault detection device that detects a ground fault in the energized state of the circuit, wherein the plurality of an input switching means that is connected to a ground fault detection point and switches the detection point to be input to the ground fault detection device according to a switching command; and an input switching means that controls the switching command and selects the output of the ground fault detection device from the switching command. An automatic ground fault detection device comprising: a control means for determining a ground fault location; and a recording means for recording ground fault location determination data of the means. 2. The automatic ground fault detection device according to claim 1, wherein the switching command and the output of the ground fault detection device are transmitted via a communication line, and the control means and recording means are located remotely.