Does any one have any info on installation of a M7100 with an external Bell? I can not find any info in any of my manuals.
Depends on how to want to connect it. You can plug a bell right in the phone itself or use the "Aux Ringer" option.
Not sure exactly what info you are looking for.
So I will suggest a couple ways.
1) External Bell runs off analog ring.
Set up the Bell off an ATA unit. Then assign the ATA either the lines you want to ring, or (as your post says) if you want it to ring anytime the M7100 rings, then set the ATA as the DN that you want to be called - then set up the M7100 with ANSWER DN for the ATA extension.
2) External Bell runs off Closed switch.
Set up the Bell to run off the AUX RING contacts (no voltage remember-just dry contact). Then on the M7100 turn on AUX RING=YES
on the bottom of the M7100 there is a plug in for an aux. ringer. I have used this once, but can not fined any of the info on it now. The Aux ringing contacts in the KSU are already being used for and other phone.
An ATA will work I am looking for options now..