JPS6237020A - Common power source circuit apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a common power supply circuit device that stably operates a shared contact amplification relay that provides operating contacts to a plurality of operating circuits with different power supplies. .

[Technical background of the invention and its problems]

When multiple operating circuits with different power sources operate under the same conditions, contact amplification is required if the number of contacts corresponding to the conditions does not reach the number of operating circuits.

Recently, power plants and large industrial plants have been centrally controlled, and with the diversification of plant layouts cables have been used for connections, resulting in the need for control power supplies to be split up and contact amplification. Sexuality is also increasing.

FIG. 2 shows that a plurality of operating power supplies RtT, R2-T are connected from a common detection contact 1 through a contact amplification relay 2 to a normally open contact 3 and a normally closed contact 5 to each relay 4. , 6 are turned on and off.

In this case, the contact amplification relay 2 is connected to one operating power supply R, -71
Since it is connected to the circuit of operation power supply R1-T, ,
If R and -T2 are both normal, when detection contact 1 closes, the contact amplification relay operates, contact 3 closes, contact 5 opens, relay 4 turns on, and relay 6 turns off.

When detection contact 1 is open, contact amplification relay 2 does not operate, contact 3 is open, contact 5 is closed, relay 4 is turned off, and relay 6 is turned on.

However, even if the operating power supply R2-T2 is normal, if the operating type gR1-T is lost, the contact amplification relay 2 will not operate even if the detection contact 1 is closed, the relay 4 will continue to be off, and the relay 6 will also be closed. The relay 6 continues to be on, and therefore, even if the operating power supplies R and -12 are normal, the relay 6 will malfunction.

Further, when the operating power source R2-T2 is lost, the relay 6 remains off regardless of the open/closed state of the detection contact 1, and therefore becomes unrelated to the operation of the contact amplification relay 2.

From the above two points, it is at least necessary to cause the contact amplification relay 2 to perform the correct operation corresponding to the open/closed state of the detection contact 1.

For this reason, conventionally, as shown in Fig. 3, contact amplification relay 2
Operation power supply R1-T□, II2-T2 as the operation power supply of
Separately, an uninterruptible stabilized power source 7 is used, but this not only increases cost but also causes trouble in maintenance and inspection since failure of the stabilized power source itself becomes a problem.

[Purpose of the invention]

The present invention provides a common power supply circuit device that uses any one of a plurality of operating circuit power supplies that is normal as the operating power supply of a contact amplification relay, thereby improving the reliability of the operating circuit without using a special stabilized power supply. It is intended to.

[Summary of the invention]

The present invention provides a power supply abnormality detection circuit that detects a voltage abnormality of a plurality of operation power supplies that serve as power sources for each operation circuit, a power supply selection circuit that selects one of the normal operation power supplies according to the detection output, and the A power supply switching circuit is provided which outputs the selected operating power source to each of the operating circuits as an operating power source for a common contact amplifying relay according to the selected output, and the contact amplifying relay is always operated with a normal operating power source. This is a common power supply circuit device that improves the reliability of the operating circuit without using a special power supply device such as a stabilized power supply.

[Embodiments of the invention]

An embodiment of the present invention is shown in FIG.

In FIG. 1, 8 is a common power supply circuit device.

Two operating power sources R knee T1. R, -T2 are input, a power supply abnormality is checked, a normal operating power source is selected, and the operating power source R-T of the contact amplification relay 2 is output.

The common power supply circuit device 8 is a voltage abnormality detection circuit 9A.

9B, a power supply selection circuit 10A, an IOB, and power supply switching circuits 11A and 11B.

When the operating power supply R1-T□ is normal, the output 12 of the voltage abnormality detection circuit 9A becomes °゛1'', and the power supply selection circuit 10A
The output 14 becomes .degree.1'', and the power supply switching circuit 11A is made conductive to connect the R knee T1 to RT.

If the operating power supply R2-T is normal, the voltage abnormality detection circuit 9
If the output 13 of B becomes "1" and R1-T is abnormal, the output 12 of the voltage abnormality detection circuit 9A becomes "O"'. Under these two conditions, the output 1 of the power supply selection circuit 10B becomes "1".
5 becomes II I II (at this time, power supply selection circuit 1
(The output 14 of 0A1 is ``0''''), the power supply switching circuit 11A is non-conductive, the power supply switching circuit 11B is conductive, and the normal operating power supply R2-T2 is output as RT.

As a result, the operating power supplies R, -T1. The normal power supply of R2-T2 (when both are normal, priority is given to R1-T) becomes the operation RT of the contact amplification relay 2, and the contact amplification relay 2 is stably operated.

〔Effect of the invention〕

As explained above, according to the present invention, when a plurality of operation circuits each have an operation power source and are operated via each contact of a common contact amplification relay, abnormalities in the plurality of operation power sources are checked. Since the common contact amplification relay mentioned above is always connected to a normal operating power supply, a highly reliable common power supply circuit device that operates the contact amplification relay stably can be realized without using a separate power source such as a stabilized power supply. .

Although the above embodiment uses alternating current as the operating power source, the present invention can also be applied when using a direct current power source.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention, and FIGS. 2 and 3 are conventional operating power supply circuit diagrams, respectively. 1 Detection contact 2 Contact amplification relay 3 Normally closed contact 5 Normally closed contact 4.6 Relay 9A, 9B Voltage abnormality detection circuit 10A, IOB @ source selection circuit 11A, IIB flX source switching circuit (8733) Agent Patent attorney Sho Inomata Akira (and 1 other person) Kaya! Figure 2 Leap

Claims (1)

[Claims] a power supply abnormality detection circuit that detects a voltage abnormality of a plurality of operation power supplies that serve as power sources for each operation circuit; a power supply selection circuit that selects one of the normal operation power supplies according to the detection output;
A common power supply circuit device comprising a power supply switching circuit that outputs the selected one operating power source to each of the operating circuits as an operating power source for a shared contact amplification relay in accordance with the selected output.