JPH0879987A - Power load monitoring system - Google Patents

Abstract

PURPOSE: To provide a power load monitoring system which can monitor with a simple display unit without limits in the installing place and the number of the display units without wiring a dedicated signal transmission line and in which the display response at the time of overload is rapid. CONSTITUTION: The power load monitoring system comprises a plurality of plug socket circuits 601,..., 60n connected to a commercial power distribution board 2, a load current measuring unit 7 connected to the circuits 601,..., 60n via current transformers CT601,..., CT60n to measure a load current, and display units 19, 20 in which the measured data of the unit 7 is superposed on a power line connected to the board 2 and transferred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power load monitoring system for monitoring the load current of an outlet circuit of a commercial power supply in an office building and preventing the breaker from operating due to overload.

[0002]

2. Description of the Related Art Conventionally, when an OA device is used and a power failure occurs suddenly, the data input up to that point is lost. This is often a lot of OA on a particular outlet circuit.
This is the result of the circuit breaker operating when equipment is connected and overloaded.

In most cases, the user generally does not know the configuration of the outlet circuit, and if there is an outlet, the load is always connected to the outlet. However, the result has the drawback that it causes a serious work loss.

Conventionally, there is a load current measuring device for measuring a load current. In this load current measuring device, the measured current value is transferred to a monitoring device through a signal transmission line provided therefor. Further, the monitoring device determines whether or not the overload state has been reached. For that reason, the transfer of the current value measured from the load current measuring device is constantly repeated.

[0005]

In the above-mentioned conventional apparatus, since a line for signal transmission is separately required, the construction and maintenance costs are high, and the installation location of the monitoring apparatus must be fixed. Further, since the monitoring device performs all the collection of the current value and the determination of the overload state, the monitoring device is required to have a relatively large processing capacity.

When the number of circuits to be monitored increases, the traffic of the signal transmission line for collecting the current value tends to become large. Therefore, the polling method is used to avoid complicated traffic control and at the same time the collection time interval is lengthened. Since it does not exist, there is a problem that the response becomes slow.

The present invention has been made in view of the above circumstances, and it is possible to monitor with a simple display device without wiring a dedicated signal transmission path, without limiting the installation place and the number of display devices. It is an object of the present invention to provide a power load monitoring system in which the display response when an overload occurs is also quick.

[0008]

In order to achieve the above object, a power load monitoring system of the present invention comprises a plurality of commercial power load circuits connected to a commercial power distribution board, and a commercial power load circuit for each commercial power load circuit. A load current measuring device that is connected via a current measuring device to measure a load current; and a display unit that transfers measurement data of the load current measuring device by superimposing it on a power line connected to the commercial power distribution board. It is characterized by doing.

Further, the power load monitoring system of the present invention comprises a plurality of commercial power load circuits connected to a commercial power distribution board,
A load current measuring device connected to each commercial power load circuit through a current transformer to measure a load current and detect an overload condition in which the measured value exceeds a set limit value, and a load current measuring device The load state detection signal is superposed on a power line connected to the commercial power distribution board and transferred, and a display unit for issuing an alarm is provided.

[0010]

With the above means, the present invention uses the commercial power line to transfer the load current measurement data value and the overload state detection signal to the display device, thereby eliminating the need for a dedicated line for signal transmission. The installation of the measuring device becomes easy, and at the same time, the display device can be monitored regardless of where the commercial power source is connected to any outlet, so that the installation condition of the display device is greatly eased.

Further, since the display device has a function of merely receiving and displaying the overload state detection signal, it does not require a large processing capacity, and an extremely small-scale device is sufficient. Also, there is no limit to the number of installations.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a configuration explanatory view showing one embodiment of the present invention. FIG. 2 is a configuration explanatory view showing an example of the load current measuring device of FIG. FIG. 3 is a configuration explanatory view showing an example of the display device of FIG.

That is, as shown in FIG. 1, the distribution boards 2, 3 and 4 are connected to the low-voltage branch board 1 of the commercial power source through the commercial power line. A plurality of outlet circuits 601, 602, ..., 60n are branched and connected to the distribution board 2 via a breaker 5. Each outlet circuit 601, 602 ………… 6
0n is the corresponding breaker B601, B602 ...
... B60n and multiple outlets C601, C602 ...
...... It is composed of a load circuit in which C60n is connected in series by a commercial power line. Each of the breakers B601 and B602
……… B60n and outlets C601 and C602 ………
The current transformers CT601, CT602, ..., CT60n are connected to the commercial power lines between the current transformers C60n, CT60n, and CT60n, respectively.
The output of 0n is connected to the input terminal of the load current measuring device 7, and the output terminal of the load current measuring device 7 is connected to the breaker 5 via the breaker 8. The outlet C
A load such as an OA device is connected to 601, C602 ... C60n.

A branch circuit 10 is connected to the distribution board 3 via a breaker 9, and the breaker 1 is connected to the branch circuit 10.
A load current measuring device 12 is connected via 1. An outlet circuit 14 and a branch circuit 15 are connected to the distribution board 4 via a breaker 13, and the outlet circuit 14 is composed of a breaker 16 and a plurality of outlets C17 connected in series by a commercial power line. A display unit 19 is connected to the branch circuit 15 via a breaker 18. A display unit 20 is connected to the outlet C17.

That is, the outlets C601 and C602
When the load OA device is connected to C60n, the load current flowing in the outlet circuits 601, 602, ..., 60n is measured by the load current measuring device 7. The measurement data measured by the load current measuring device 7 is superimposed on the power line connected to the commercial power distribution board 2 and displayed on the display units 19 and 20.
Transferred to.

The load current measuring device 7 is connected as shown in FIG. 2, and as a result, CT601, CT602 ...
An AC current proportional to the load current flows in 0n, and this AC current is converted into a DC voltage by passing through the rectifier circuit 22 and then converted into digital data by an A / D converter (analog / digital conversion circuit) 23. This A
The output data of the A / D converter 23 is fetched by the control module 24 and compared with a set value, and when the set value is continuously exceeded for a set fixed time, it is determined that an overload state has occurred, and an alarm is issued. An overload detection signal consisting of a message and a data packet including the unit number of the device and the number of the overloaded circuit is connected to the commercial power distribution board 2 by the spread spectrum power line driver 25 in the control module 24. It is transferred to the display units 19 and 20 while being superposed on the commercial power line.

On the other hand, when the display section 20 is connected to an appropriate outlet C17 as shown in FIG. 1, an alarm message transmitted by the receiver section 27 of the control module 26 superimposed on the commercial power line is transferred as shown in FIG. The overload state detection signal including the data packet including the data is included, the alarm source is displayed on the 7-segment display 29 through the driver module 28, and the LED lamp 30 is displayed.
Is lit and the buzzer 31 is activated.

The push buttons 32 and 7 of the display unit 20 are
By using the segment display 29, a command packet for changing the current for overload monitoring and the time constant can be issued to the load current measuring device 7.

As described above, since the dedicated signal transmission line is not required and the monitoring device is inexpensive,
Since it becomes possible to easily and economically realize a system that monitors the overload of the outlet circuit of the commercial power supply, the outlet circuit is unknowingly overloaded, the breaker of the circuit operates, and the load suddenly loses power. It becomes possible to easily prevent the situation where important data is lost in advance, which contributes to the improvement of the safety of business activities.

[0020]

As described above, according to the present invention, a commercial power line is used to transfer the load current measurement data value and the overload state detection signal to the display device, thereby wiring a dedicated signal transmission line. Without the need to install the display device,
You can monitor with a simple display device without the limitation of the number of items,
It is possible to provide a power load monitoring system with a quick display response when an overload occurs.

[Brief description of drawings]

FIG. 1 is a configuration explanatory view showing an embodiment of the present invention.

FIG. 2 is a structural explanatory view showing an example of the load current measuring device of FIG.

FIG. 3 is a configuration explanatory view showing an example of the display device of FIG.

[Explanation of symbols]

1 ... Low-voltage branching board, 2, 3, 4 ... Distribution board, 5, B601,
B602 ......... B60n, 8 ... breakers, 601,60
2 ... 60n ... Outlet circuit, C601, C602
……… C60n… Outlet, CT601, CT602
… CT60n… Current transformer, 7… Load current measuring device, 1
9, 20 ... Display section.

Claims (2)

[Claims] 1. A plurality of commercial power load circuits connected to a commercial power distribution board, a load current measuring device connected to each commercial power load circuit through a current transformer to measure a load current, and the load. A power load monitoring system, comprising: a display unit in which measurement data of a current measuring device is transferred by being superimposed on a power line connected to the commercial power distribution board. 2. A plurality of commercial power load circuits connected to a commercial power distribution board, and load currents connected to the respective commercial power load circuits via current transformers to measure load currents and set limits for the measured values. A load current measuring device that detects an overload condition exceeding a value, and a display unit that issues an alarm when the overload condition detection signal of the load current measuring device is transferred by being superimposed on a power line connected to the commercial power distribution board. An electric power load monitoring system comprising: