It is used to monitor and supervise the integrity of a circuit breaker s trip coil and other wiring circuits of low voltage and medium voltage networks.
Trip coil supervision circuit.
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.
So in order to check the condition of the trip circuit is essential in power system protection.
The 7pj13 trip circuit supervision relay is an electronic circuit based relay.
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.
Failure of trip supply open circuit of trip coil of trip circuit wiring.
Pre close trip supervision post close trip supervision.
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.
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.
Trip circuit supervision relay is provided to monitor the healthiness of trip coil.
The relay is a member of siemens reyrolle protection devices product family.
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.
With references for single pole and 3 pole and a wide range of voltages vdf.
Arteche trip circuit supervision relays monitor trip coil circuit in open close states and during circuit breaker operation.
Pre closing supervision and post closing supervision circuits are used to sense the trip coil healthiness.
Both versions detect the following conditions.
We will be using areva make vax31 type trip circuit supervision relay.
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.
Trip coils are nothing but an electromagnetic coil which is used to trip the circuit breaker during the fault condition.
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.
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.
This relay has three coils namely rla rlb and main coil tcs of the relay as shown in the figure above.
