FXO CO trunk line power failover

[chsu]

How do I design a power failover to analog trunk lines to CO. For example, I have PRI line connected to my VG200 gateway. I also have 8 analog lines from CO that currently connect to the FXO ports on another VG200. These two VG200's also have 4 FXS ports that are currently connect to 4 analog phones. What I would like to be able to do is to have these analog phones get power from the CO when the building power goes out and UPS shuts down. Gordon Kapes has many PFT (power failure transfer) devices but they all seem to designed for legacy PBX's. In the case of Callmanager, you will have to walk to the computer room or wiring closet and manually plug the phones to the jacks. These PTF's will even do automatically transfer for the PBX's.

http://www.gkinc.com/PDFFiles/bp5atp_2.pdf

[r-reed]

This works. THe PFT device will connect the FXS and FXO ports on the VG200s and the CO lines and analog phone lines. When the power fails the unit will switch the CO lines to the analog phone lines. When powered, the CO lines will be connected to the FXO ports and the phones to the FXS ports. See http://www.gkinc.com/PDFFiles/BPds_1.pdf for a diagram of the PBX version.

[pcantore]

If you're buy new analogue only equipment, there is a net module for 2600/3600/3700 - the NM-HDA, provides upto 2 (I think) power fail FXO to FXs bypass ports when the router is powered down - haven't played with one so don't know if there's CLI to toggle operation.