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(d) Interlocked Relays: These relays are available in 4F/4B, 5F/3B & 6F/2B contact
configurations. The ohmic values of these relays are 615ohms for all contact configuration.

(e) AC immunised relay (Both Top & bottom Relays): These relays are available in 5F/3B
contact configuration only. The ohmic values of the relay is 1840 ohms only.

(f) AC immunised relay (Top AC immunised & bottom Non AC immunised Relay): These
relays are available in 5F/3B contact configuration only. The ohmic values of the top
relay is1840 ohms and bottom relay is 1260 ohms only.

7.0 Metal to Metal Relays - Misc Relays

(a) Double Coil Relays: These relays are commonly used as Z1WR1, Z1NWR, Z1RWR,
WKR3, Z1WR, WLR in point control circuit. These relays are available in 5F/3B contact
configuration only. The ohmic values of the top relay is 1340 ohms and bottom relay
is 1590 ohms only.

(b) Universal ECR: These relays are available in 3F/3B contact configuration only. The
ohmic values of the relay is 83.1 ohms only. It is used as lamp proving relay.

(c) WKR1: These relays are available in 5F/3B contact configurations. The ohmic values of
these relays are 1840 ohms only. It is a part of Point minor group and Point Major
group. It is used for point detection.

(d) WKR2: These relays are available in 5F/3B contact configurations. The ohmic values of
these relays are 1840 ohms only. It is a part of Point minor group and Point Major
group. It is used for point detection.

(e) WJR: These relays are available in 2F/2B contact configurations. The ohmic values of
these relays are 1840 ohms only. It is a part of Point minor group and Point Major
group. It is used to provide 10 sec time duration for point operation.

(f) WR (Heavy Duty contactor Relay): These relays are available in 2F/2B contact
configurations. The ohmic values of these relays are 60 ohms only. It is a part of Point
minor group and Point Major group. It is used for point motor operation

(g) Siemens Motorised Clockwork Timer: This relay works on 11 OV A.C. +/- 10%. It has
a time range of 1 to 5 minutes. The time can be adjusted. Its resetting is automatic. A
synchronous motor drives and switches over contacts after the lapse of preset time. If
the energising circuit is prematurely interrupted, the mechanism returns to its normal
position before actuating the contacts. Usage: These relays are used to count time
delay.

Chapter 21: Relay & Electronic Interlocking Page 468 of 535