COMMON FERRULE NUMBERS USED IN WIRING DIAGRAM

COMMON FERRULE NUBERS

 A:    CT secondary connection for primary protection like Differential, Distance, REF Relay). Small “a” used for PT secondary connection in PT terminal box.

B: Bus bar Protection (CT secondary connection). B for B phase indication.

C: Back up Protection (CT secondary connection for O/C & E/F Relay).

D: Metering (CT secondary connection).

E: Metering & Protection (PT secondary connection).

H: A.C. connection.

J:   D.C. connection (Before Fuse).

K: D.C. connection for control (After Fuse).

L:   D.C. connection for Indication (After Fuse).

M: Motor Supply (Spring charging Motor in Circuit Breaker).

N:   RTCC (Tap Changer) connection. Also for denoting A.C. Neutral connection.

P:   PT primary connection & DC circuit of Bus bar protection scheme.

R:   R Phase Indication.

S:   CT secondary connection in Terminal Box.

U:   Circuit Breaker auxiliary contacts.

X:   TB Numbering.

Y:   Y Phase Indication.