Siemens UL 1066 Operating Instructions Manual page 25

5.3.1.3 Key interlocking of fuse carriage and FS III fused circuit breaker
The racking mechanism for the fuse carriage is interlocked with the associated fused circuit breaker. In order to rack the fuse carriage, the
associated fused circuit breaker must be open, and the KIRK key must be removed from the circuit breaker, which unlocks the racking
mechanism of the fuse carriage.
(1) Fuse carriage FS III
(2) Circuit breaker FS III
(3) Interconnenction between cradles, according to the rated current of the circuit breaker.
line or load
(1)
(3)
(2)
line or load
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