When the EnviroMon network is being set up there are several alarm options that can be configured for each sensor.
High and low threshold
Alarms can be enabled or disabled for each sensor. Enabled sensors can have both high and low thresholds. It may be desirable to have an alarm on sensor failure, but not if a parameter goes out of range. This can be done by leaving the alarm enabled and setting a wide parameter range.
If the parameter normally goes out of range for short periods, it is possible to hold off (delay) alarms for a specified period. For example, if a freezer periodically goes through a defrost cycle lasting 15 minutes, an alarm hold off of 20 minutes would prevent the defrost cycle from causing alarms.
If it is necessary to keep the parameter in range only during working hours, it is possible to specify the time range and days of the week that the alarm should be enabled. It is also possible to disable the alarm during holiday periods.
The deviation alarm can only be enabled when an EL042 is connected to the EnviroMon network. With this advanced feature you can set up the EnviroMon system to monitor a number of channels as a group. The EL042 can then activate an alarm if any channel differs from the group average, or from any other channel in the group, or from the median of the group, by more than a specified amount. You can even define nested groups of sensors.