Alarm Hysteresis; Standby Sequence; Alarm Latch - Omron E5CN User Manual

Alarm Hysteresis

4-2

Alarm Hysteresis

4-2-1

Standby sequence

Restart
4-2-2

Alarm latch

44
• The hysteresis of alarm outputs when alarms are switched ON/OFF can
be set as follows:
Upper-limit
alarm
Alarm hysteresis
ON
OFF
Alarm value
• Alarm hysteresis is set independently for each alarm in the "alarm hyster-
esis 1" and "alarm hysteresis 2" parameters (advanced function setting
level). Default is "0.2".
• "Standby sequence" is a function which allows the alarm outputs to be
temporarily disabled while the first alarm condition occurs. From here on,
the alarm output is active for future alarm conditions.
• For example, in a standard heating application, if you used the standard
"low alarm", the alarm would be active from switching the controller ON.
However, with "Standby Sequence", the alarm output is disabled during
the first warmup, and the temperature has to rise above the alarm set
point before the alarm can become active. Then, if the temperature falls
below the alarm set point, the output is active.
• The standby sequence is canceled when an alarm is output. It is, how-
ever, restarted later by the "standby sequence" parameter (advanced
function setting level).
For details, see the "standby sequence" parameter in "Section 5, Parame-
ters."
• "Alarm latch" is a function where alarm output once turned ON stays ON
regardless of the temperature.
• The alarm latch can be canceled by turning the power OFF. (Note, how-
ever, that it can also be canceled by switching to the initial setting level,
communications setting level, advanced function setting level or calibra-
tion level.
Section 4-2
Lower-limit
alarm
Alarm hysteresis
ON
OFF
Alarm value