With a Standard M30 further call-outs in a duty Roster are stopped by telephoning the M30 back (or using the DTMF ‘0’ feature). Thus no further calls will be made by the M30 UNLESS either the alarm channel(s) that caused the the dial-out reverts back to a normal condition, and then re-activates or another alarm channel becomes active. The Recycle after Cancellation feature allows a time period to be set (e.g. 30 minutes) whereupon the M30 will begin the dial-out sequence again. This feature is ideal where personal are expected to have arrived on site to resolve the problem and have for some unknown reason failed to do so. An example may be that there is a High temperature alarm and the M30 has called the first member of staff on duty. The member of staff calls back the M30 to stop further calls being made and sets of to deal with the problem, whereupon the car breaks down or he/she has an injury and therefore fails to arrive on site.