I would like to know if it is possible to setup the system not to require 9 to reach PSTN? I saw this question on an FAQ regarding PSTN connectivity, and it was answered "You can configure the UC500 in keysystem mode, where the user can seize available FXO or T1 CAS to dial numbers directly to CO."
I have our UC500 currently configured as a keysystem, with our PSTN/FXO dial peers set up as shared-dn's on all the phones. On our old phone system, it was possible to just press a line button and begin dialing a number, or just pick up the phone and a line was automatically selected and you could being dialing (without having to dial a number).
Is it possible to do this on the UC500, and if so, how would you go about configuring it?
If you are just picking up the handset or pressing speaker to make the call, then you are going offhook on the internal line and you do indeed need to dial 9 to reach the PSTN, even though this is a key system. To avoid dialing 9, you need to explicitly select a CO line to place the call on by pressing the corresponding button. When you do this, you are immediately connecting to the associated phone line, will hear dial tone coming directly from the telephone exchange, and will be able to place calls without dialing 9.