Deadband is an area of the alarm range where no reset action occurs. The purpose of the deadband is to prevent unintentional activation-deactivation cycles.
For example, an out of range alarm has an upper limit of 10 and the deadband is 2. The monitored variable must be equal to or fall below 8 (10-2) before the triggered alarm is reset.
Deadband can be set for out of range alarms and out of reference range alarms.