Yes, the intruder alarm system will still work without a telephone dialler. However, in case of an intrusion, the main panel will only alert the sounders to go on and there will be no way of alerting you by telephone. The telephone dialler’s job is to call the numbers which are saved in its memory to alert the property owners. A pre-recorded message is saved as well, which will be heard once a call from the dialler is done. One can assign up to five numbers which the dialler calls in a sequence upon an intrusion. The first number assigned is usually that of the owner, whilst the second number is usually that of the police depot. When the dialler’s call is answered, the person taking the call will hear the pre-recorded voice message and, in case of the police, send the closest patrol.