Verilink AS420 (34-00294) Product Manual - Manual (Page 20)

12 A S 4 2 0 R e f e r e n c e M a n u a l
The power bypass mode is done using relays that switch the network and
equipment connections. When the unit is powered and stable, the relays have
the network and equipment connections switched into the AS420’s internal
circuitry. When the unit loses power, the relays switch the network connection
to a direct connection path to the equipment connection. When power is
reestablished and the unit passes self test, the relays switch the network and
equipment connections back into the AS420’s internal circuitry.
The AS420 powers up and remains in the power bypass mode for two
minutes. This delay allows for any power glitches that may occur as power
resumes after an outage. This minimizes the unit switching from power
bypass to normal operation.