From the manual
"DURESS EMERGENCY (SILENT DIAL OUT)
If you wish to have a button in your home that activates a SILENT dial out, (no lights flashing and no sounder) it should be connected to a zone that is configured as a DURESS EMERGENCY. If this zone is accidentally tripped, you will not know that the OmniPro II is making a silent dial out, and hence won't know to stop it.
To stop a silent dial out once it has started, you must go to the console and press OFF then enter your code."
Other related info
"The digital communicator will not dial out until the DIAL OUT DELAY has expired. If the alarm is canceled prior to the expiration of the DIAL OUT DELAY, no transmission will take place. After the DIAL OUT DELAY has expired, though, all alarm trips will be transmitted followed by a CANCEL code.
When the digital communicator is used, all voice dial outs will be delayed for five minutes after the expiration of the dial out delay to allow time for the central station to call the premises after an alarm code has been sent. If the digital communicator is unable to successfully communicate with the central station, the user will be alerted to the trouble condition. When the system status is requested using the voice, this condition is reported over the phone as "SECURITY PHONE MESSAGE" trouble"
" When an alarm is activated, the OmniPro II will wait the Dial Out Delay. If your system is monitored by a central station, it will be notified first. Then the voice dialer will dial out to the numbers as described above.
If the alarm is turned off at the console while a voice dial-out is in progress, the dial-out will be canceled immediately and the voice dialer will hang up. If the number dialed is busy, or if all lines are busy, the dialer will immediately hang up and go to the next number in the Dial Order. The dialer will wait up to 45 seconds after it finishes dialing for a voice to answer the call. If it doesn't hear a voice in that time, it goes on to the next number. The voice dialer will respond to answering machines.
After it has dialed the last number in the dial order, the OmniPro II stops dialing and reconnects the in-house phones."
Hope this helps!
