Trailer Signal Device Schematic Diagram

The warning signal device is a device that can automatically emit audio and optical card light signals when the equipment fails or some abnormal operation conditions. It can help operators to detect faults and hidden dangers in time to take appropriate measures to deal with them and prevent the expansion of accidents.

Common warning signals of substation include: light gas action of transformer, transformer overload, high oil temperature of transformer, secondary circuit disconnection of voltage transformer, DC circuit insulation reduction, control circuit disconnection, circuit fuse of accident audio signal, high or low DC voltage.

Trailer signals are generally sent from individual relays monitoring operating parameters such as overload signals by overload protection relay.

The warning signal is divided into instantaneous warning signal and delay signal. Some warning signals that may be accompanied by a short circuit failure in the power system, such as overload and voltage transformer secondary circuit disconnection, shall be issued with delay.

The delay shall be greater than the maximum removal time limit of the external short circuit. Thus, these abnormalities caused by the system short circuit automatically disappear without sending an alarm signal to distract the operator.

At present, the trailer signal device with repeated action has the same action principle as the accident audio signal device with the alarm bell. FIG. 11 shows the wiring diagram of the ZC-23 type impact relay. The action principle is similar to FIG. 9. The Fig. KM1 is drawn by FIG. 15 to automatically remove the sound, and WSW1 and WSW2 are the instantaneous warning busbus.

When the equipment is abnormal, For example, the control circuit disconnection,  KBC2 action, Its normally open contacts are closed, Open contacts →HP2→WSW1 and WSW2→ST13-14→ST15-16→KSP2→-WS, through the loop +WS→KBC2  Make KSP2 action, Contact KM2 is closed, Let the alarm HA to a sound signal, Meanwhile, the optical card HP2 shows the "control circuit disconnection" signal, Press the Release button SCL, The sound can be lifted (or by a certain delay, Automatic Release), And the optical card signal is until troubleshooting, The KBC2 contact returns disappears. Since the ZC-23 type relay is adopted, the signal can be repeated.

In order to regularly check the integrity of the light bulb, set the switch switch ST. In the close position, the ST contacts 1-2,3-4,5-6,7-8,9-10,11-12 are fully on, connecting the signal power supplies + WS and-WS to the small bus WSW2 and WSW1, to illuminate all light bulbs. When warning, the two bulbs are in parallel and still visible when one of them is damaged. When testing the light card, the two bulbs are in series, so the light is dim, and if one bulb is damaged, the light card is not bright.

The trailer signal device is powered by a separate fuse FU3, FU4, and is not emitted if the FU3 or FU4 fuse, so light monitoring is used for the fuse power supply. Figure 11 shows the wiring diagram of the fuse monitor lamp of the trailer signal device. During normal operation, the fuse monitor relay K2 is charged, the white indicator light HW on the central signal screen is on; when the FU3 is blown, the K2 loses power, the normally closed contact is closed, and the HW is connected to the flash small bus (+) WTW.