With “Fail Safe” door opener:
The locking latch is only released when the operating voltage is absent (rare type,
used, for example, for escape route doors, as the door can be opened in the event
of a power failure).
A “Fail Safe” door opener
B Power adapter
C Code lock
D Door opener button (NO contact, normally open contact)
E Door sensor (NC contact, normally closed contact)
F Protection diode: The protective diode must be connected near the door opener with the
correct polarity. This protects the code lock from voltage peaks.
G Alarm siren
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