If I understand you correctly, this is possible.
The ATLAS routes calls through the DIAL PLAN based on the IN#ACCEPT and OUT#ACCEPT lists. I assume you are using the “$” as the OUT#ACCEPT on your primary PRI. If you want outbound calls to use the backup
PRI when the primary is unavailable you can configure it with an OUT#ACCEPT of “$” as well and set the SEARCH to SECONDARY. When you configure a SECONDARY search, the “Accept Number” must be exactly the same as the PRIMARY “Accept Number” or it will not be used. (There must be a PRIMARY in order for there to be a SECONDARY.)
We haven't seen any follow-up questions on this, so I am going to mark it as "assumed answered". If it is not answered or you need additional information please let us know.
I went back to this site and we still experience this problem. I've verified the programming/configuration is correct. What happens, if the main PRI circuit is out, calls bounce back to the PBX as received incoming digits and the auto attendant answers. They never hit the second PRI circuit which is running and never goes out.
If you are using "$" as your IN#ACCEPT under the USER TERM, and the SEARCH is PRIMARY, then this will be used before the NETWORK TERM entry that has a SEARCH of SECONDARY. SECONDARY will only be used if there is no PRIMARY search for the same number or pattern. I suggest changing your IN#ACCEPT to be more specific for the numbers you are expecting to receive on inbound calls. Alternatively, you can set both NETWORK TERM PRIs with a SEARCH of PRIMARY, and the ATLAS will use them in the order they are listed (top down).
Hope this helps,