Can I make calls with my SBCS / UC500 systems even if the power goes out?
Yes, there is a power failure feature included (primarily this allows for emergency calls to be completed even if UC520 is down):
The ports that allow for this are mapped as FXS port 0/0/3 to FXO port 0/1/0. An analog phone must be plugged into the FXS port. The PSTN line gets plugged into the FXO port.
To verify this:
Unplug the power at the back of the UC520
- Go off hook on the analog phone – you should still get dialtone on the analog phone. Dial any number and you are directly connected to an outside carrier.
Andrew Lee Lissitz
I have this problem too.