Atlas 550 was powered up with no T1 / PRI plugged in but no alarms are showing.
Is the T1 configured as part of a dial plan or dedicated map? If it isn't configured it won't generate any alarms.
Until the ATLAS has been configured, it shouldn't show any kind of alarms on the front panel. If you go under MODULES, and then go into the ALARM menu, it should show an asterisk next to LOS and RED if nothing is plugged into the port.
FXO ports do not deliver dial tone, they receive loop current and dial tone from an analog line (phone line). FXS ports provide dial tone and loop current, but will only do that once configured in the DIAL PLAN or DEDICATED MAP - and if in the DED MAP, will only pass what is provided on the T1 that the port is mapped to.
Hope this helps,
Patrick
I will check to see if the program got dumped. This unit has been in service for several years as a backup. It is normally powered down, Is memory held by backup battery?
The configuration is held in NVRAM, but if you look at this discussion (Re: Atlas 550 Loses Config ) The batter in the NVRAM chip CAN go bad.
Yep, it's one of the Mostek/Dallas "timekeeper" chips with an epoxied-in-place battery, and the chip is soldered in place.
If you're equipped to work on through-hole components you can replace it. I strongly advise putting in a socket rather than soldering the replacement chip to the board.
It's good that you discovered this now. Much less fun is a box that's in production and has been on a UPS for the last several years, then the UPS takes a hiccup. Don't ask me how I know this.