Key-Operated Interlocks; Key-Operated Interlocks For The Withdrawable Part / Switching-Device Truck - Siemens NXAIR Operating Instructions Manual

25 Key-operated interlocks

25.1 Key-operated interlocks for the withdrawable part / switching-device truck

Function and design
Key-operated interlocks are available for circuit-breaker, disconnecting and contactor panels. Access to the
key of any interlock is given with closed high-voltage door.
Key-operated interlocks allow interlocking or releasing associated operating functions depending on the state
of the operated device. Key-operated interlocking is available for the following functions:
•
If the withdrawable part / switching-device truck is racked to test position, racking it to service
position can be interlocked by turning and removing the associated key.
•
If the feeder earthing switch is in OPEN position, switching it to CLOSED position can be interlocked
by turning and removing the associated key.
•
If the feeder earthing switch is in CLOSED position, switching it to OPEN position can be interlocked
by turning and removing the associated key.
The interlocked functions can be released again by reinserting the associated key, and subsequently turning
it in opposite direction.
For customization, the interlocking options are available individually and can be combined at will. When
operating the panel, it is possible to interlock two operating functions in combination: racking the
withdrawable part / switching-device truck and changing the position of the feeder earthing switch. As the
feeder earthing switch must always be either in CLOSED position or OPEN position, removing both
associated keys simultaneously is not possible.
A cover protects the locks against accidental access. The cover is secured on the high-voltage door with a
rotary button.
Fig. 663: Example: High-voltage door with key-operated interlocks protected by cover
Left: Circuit-breaker panel width 600 mm
Right: Circuit-breaker panel width 800 / 1000 mm
110-0134.9 / 13
INFORMATION
Read and understand these instructions before attempting operating works.
NXAIR / ≤ 40 kA
Key-operated interlocks
(1) Cover
Rotary
button to
(2)
secure the
cover
365