Trip Coil Supervision Circuit

Pre closing supervision and post closing supervision circuits are used to sense the trip coil healthiness.

Trip coil supervision circuit.

The supervision function in three steady states of circuit breaker trip circuit is below image in normal condition the indicator led glows green and output relays are in picked up condition. The supervision relay type tcs is intended for a continuous supervision of circuit breaker trip circuit and gives an alarm for loss of auxiliary supply faults on the trip coil or its wires independent of the breaker position. As there are two trip coils therefore there will be two trip circuit supervision relays and hence two different circuits. Arteche trip circuit supervision relays monitor trip coil circuit in open close states and during circuit breaker operation.

This relay has three coils namely rla rlb and main coil tcs of the relay as shown in the figure above. Pre close trip supervision post close trip supervision. The relay is a member of siemens reyrolle protection devices product family. Tcs relays are used for dc supervision via lor trip coil generating an alarm and avoiding open close commands under faulty conditions or when breaker tripping mechanism is not ready to operate.

The 7pj13 trip circuit supervision relay is an electronic circuit based relay. Trip coils are nothing but an electromagnetic coil which is used to trip the circuit breaker during the fault condition. With references for single pole and 3 pole and a wide range of voltages vdf. There are different contacts connected in series along a trip circuit of an electrical circuit breaker there must be some situation when the circuit breaker should not trip even a faulty current passes through its power contacts.

Hence 95a relay gets operated and so its contact is closed and so positive is. So in order to check the condition of the trip circuit is essential in power system protection. Failure of trip supply open circuit of trip coil of trip circuit wiring. Permanant positive is given to one end of coil of 95a and now the other end of coil of 95a gets the negative voltage coming through the tripping coil nc auxillary contact of the breaker.

Both versions detect the following conditions. When the circuit breaker is closed post closing supervision only while type vax 31 and mvaxm 31 relays monitor the trip circuit continuously both pre closing and post closing supervi sion. Such situations are low gas pressure in sf 6 circuit breaker low air pressure in pneumatic operated circuit breaker etc in this situation the trip coil of the cb. In the event of a fault the measuring current goes below the operating value of the relay 0 3 0 7 ma or completely stops flowing.

Such trip circuit supervision tcs relays are intended for a continuous supervision of circuit breaker trip circuit and to give an alarm for loss of auxiliary supply faults on the trip coil or its wires independent of the breaker position faults on the breaker auxiliary contacts and faults in the supervision relay itself.