ABB
19
Uniswitc h Operation a nd
Mainte na nc e Manua l
UNI S14GB 05-02
Figure 3.10
Operating and interlocking mechanism of earthing switch type EM.
The earthing switch (
46.1
) (Figure 3.2) can only be switched on if the
withdrawable part is in the test/disconnected position or outside of the
cubicle (mechanical interlock) (
61.3
and
61.4
).
If the earthing switch is on, the withdrawable part cannot be moved from
the test/disconnected position to the service position (mechanical
interlock).
References
Details of other possible interlocks, e.g. in connection with a locking
magnet on the withdrawable part and/or earthing switch drive, can be
obtained from the relevant order documents.
