Ism Emergency Opening - TAVRIDA ELECTRIC VCB15 Product Manual

5.2.4 ISM Emergency Opening

The ISM can also be opened manually. To open the ISM manually, apply force to the manual trip button. See Figure
31 below.
The button moves the ISM synchronization plate. When the synchronizing plate is moved, a force exceeding the
magnetic attraction forces of the ring magnet is applied to the ISM armature, which subsequently starts to move.
As the air gap increases, the opening springs and the contact pressure springs exceed the magnetic holding force
and the vacuum interrupter opens.
Figure 31
ISM manual trip execution
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