You can google the manual, ars is a dial number to route, not for emergency calls but can be programmed to send the numbers out the correct route.

When using it for different areas you will need to use tenants and class of service.

If one site is using one trunk provider to make all calls on, including 911 calls, then that is in a tenant that doesn’t have ars enabled,

If one site has a different line for 911 then it will need ars enabled on its tenant and the dial plan configuration to send 911 on the correct line. It is complex when you have not done it before so if you can send the site clip out on all calls, that should cover you for 911 calls.

Note: I know the USA have a lot stricter emergency policy than we have, so you have to make sure what ever you do is within those policies

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