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SECTION
5 1 8-450-1 00
O K
Calls received at attendant
station or alternate location.
OK
Power failure ringers
operate.
Page 1 00
TABLE U
POWER FAI LURE TRANSFER CI RCUIT - 452A KTU
CO/PBX ringing on
line under test.
Disconnect commercial
power or remove B SIG at
power unit.
CO/PBX ringing on line.
FAI LURE
1 .
N o commercial power t o KSU.
2.
No battery and/or ground to
452A KTU-B SIG fuse on
19C-type power unit.
3 .
Defective 452A KTU.
FAI LURE
1 .
Defective 452A KTU.
2.
Improper connections at
block 1 .
3.
Ringer connected improperly
or defective.