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GEH-1753
Time Overcurrent Relays Type lAC
DEVICE FUNCTION NUMBERS FOR USE
WITH ALL EXTERNAL DIAGRAMS
50
Instantaneous Unit
51
Overcurrent, Relay, Type lAC
51N -
Ground Overcurrent Relay, Type lAC
52
Power Circuit Breaker
SI
Seal-in Unit, with Target
Trip Coil
TC
A
Auxiliary contact, closed when breaker
closes.
A-C BUS
1
2
3
.li
I
.ll::,l
Tij)pPJ•(;
..: ACTOR�
-
llcl
Fi�. 5
(K6375668-l) External
Connections of Three
Type IAC51A
R�lays used
in Conjunction
with
Tripping
Reactors
for Protection of
aTihree-Phase
Circuit,
6
A-C BUS
...
ll=1
1-1
Fig. 4
(K-6375667-2)
E
x
t
e
r
na
l
Connections of T
h
re
e
Type
IAC51A
Relays used for Phase-to-Phase
and
Ground
Ove
r
cu
r
r
e
n
t
Portection of a 3-Phase
Circuit.
A..C
BUS
Fig.
6 (K-6375669-6)
External Connections of
Three
Type
IAC51R Relays
used
for
3-Phase Circuit Protection,
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