I have a samsung 7200. running ver 4.98. SIP trunks a mgi16 and a oas card. the system is equipped with a 8sli3 card. The problem is, we are trying to connect a alarm panel to the sli port, the panel will dial out with no issue however it appears that the called number can not hear any of the tones from the panel. Will the Samsung 8sli3 support a modem? Fax machine works fine on the sli card.
Alarms and fax modems don't generally work well over SIP in my experience. Have always had to keep a pots line or have it go cellular.
Alarms on a phone system is a bad idea.
Alarm systems have a battery backup so they'll still work during power fail.
Phone systems generally don't.
Also when the internet is down, your sip trunks won't work so it can't dial out.
I've done a lot of testing with this and I've found that the dtmf tones get distorted by the provider so they alarm receiving equipment doesn't recognise them.
You can try using g.711 and setting the dtmf to inband (this emulates a pots line as best as voip can).
You may also have an issue with the voltage on the sli3 card not being exactly the same as a pots line (48-52v DC here) the sli card will likely be about half that.
Thank you. Already set to g711. Rfc2833for dtmf. Not sure if Centry Link will accept anything else. Worth a try. Thanks again Ill have to measure the voltage