Mitsubishi Electric MELSEC-Q Series User Manual page 57

3 SPECIFICATIONS
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(c) Wait alert
Choosing the wait alert ignores the alert status if the measured value
(PV)/deviation is in that status when the setting mode is changed to the
operation mode, and makes the alert function invalid until the measured
value comes out of the alert status.
Example: Selecting the lower limit deviation alert with wait makes the alert
function invalid until the process value exceeds the alert set value.
POINT
After the alert mode is set and an alert judgment starts, if the system has reached
the non-alert status even once, the wait function no longer operates.
(d) Re-wait alert
The re-wait alert is a wait alert-based feature which has the additional
function to make the alert function invalid again when the set value (SV) is
changed.
For the control required the set value change, the alert status that may
occur when the set value is changed can be avoided by setting this function.
Example: If the measured value (PV) is at the position as shown below
before the setting is changed, changing the set value (SV) for
deviation alert will put the measured value in the alert region and
turn on the alert. To prevent this, the function makes the alert wait
operation valid and the alert output to wait.
MELSEC-Q
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