Mitsubishi Electric MELSEC-Q Series User Manual page 55

3 SPECIFICATIONS
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(2) When the Q62HLC uses the alert function, additional settings (alert dead band,
alert delay count, and wait/re-wait settings) can be configured.
The following table lists the alert functions which can be used with the addition of
alert dead band, alert delay count and wait/re-wait.
Alert function
Upper limit alert
Input alert
Lower limit alert
Upper limit
deviation alert
Lower limit
Deviation
deviation alert
alert
Upper/lower limit
deviation alert
Within-range alert
(a) Alert dead band setting
When the measured value (PV)/deviation is close to the alert set value, the
alert status may alternate with the non-alert status due to input instability or
the like.
Setting an alert dead band can prevent this from happening.
An alert dead band can be set in Alert dead band setting (buffer memory
address: 164).
Example: When the dead band value is set to the upper limit input alert, the
system is placed in the alert status when the upper limit of the
input rises to or above the alert set value. The system is put in the
non-alert status when the upper limit falls below the alert dead
band.
Dead band Alert delay
setting count
MELSEC-Q
Wait Re-wait
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