What is a lockout relay used for?
What is a lockout relay used for?
Lockout relays are used by many utilities in electrical power transmission substations to trip and hold out of service a protection zone on the occurrence of a relay operation that requires inspection and/or repair before the zone may be safely placed back in service.
What does tripping relay mean?
Defination: Master trip relay is a contact multiplication or an Auxillary relay, which operates on the command from Multiple protection relays and gives a Single Commmand to the Breaker Trip Coil.
What is overcurrent relay?
An overcurrent relay is an electrical protection device designed to cut off the power supply to a circuit, appliance, or machine in the event of an overload or failure. These devices typically consist of a manual circuit breaker or contactor and a current sensing relay which interlocks with it.
What is TCS relay?
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 …
What is a 94 relay?
94 Tripping or trip-free relay A relay that functions to trip a circuit breaker, contactor, or equipment, to permit immediate tripping by other devices, or to prevent immediate reclosing of a circuit interrupter if it should open automatically, even though its closing circuit is maintained closed.
What is a MHO relay?
A mho Relay is a high-speed relay and is also known as the admittance relay. In this relay operating torque is obtained by the volt-amperes element and the controlling element is developed due to the voltage element. It means a mho relay is a voltage controlled directional relay.
What does 86 do on a relay?
Realizing that 85 and 86 are the coil pins, these pins will be transferring the current through the coil. 85 will be used to ground your relay, while 86 will be connected to the switchable power. 87 and 87a will be connected to your controlled accessories that you wish to turn on and off with your relay.
What is the difference between earth relay and overcurrent relay?
Over load relays are used in control and power circuits to protect the motor from over load /over current. Earth fault relay that means phase to ground fault will occur the relay gets activated but phase relay means phase to phase fault, open circuit fault and short circuit fault occuring that relay gets activated.
What are the limitations of overcurrent relay?
The disadvantage of this type of protection is that it’s difficult to coordinate and requires changes with the addition of load and that the short-circuit fault close to the source may be cleared in a relatively long time in spite of its highest current value.
