Alert Function - Mitsubishi Q Series User Manual

3 SPECIFICATIONS

3.2.10 Alert function

1) Upper limit input alert
When the measured value (PV) is equal to or greater
than the alert set value, the system is put in an alert
status. The setting range is the same as the input
range.
Measured value (PV)
Alert set value
Alert status
[When alert set value is positive]
Measured value (PV)
Alert set value
Temperature
set value (SV)
Alert status
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(1) The alert function is a function which sets the system in an alert status when the
process value (PV) or deviation reaches the alert set value. It is used to turn on
the device's hazard signal or operate the safety device.
The alert function is classified as follows:
• Input alerts ............. Upper limit input alert, lower limit input alert
• Deviation alerts...... Upper limit deviation alert, lower limit deviation alert,
If an alert occurs during the control, the control continues its operation. Output
doesn't turn off.
(a) Input alerts
Process value (PV)
(b) Deviation alerts
1) Upper limit deviation alert
When the deviation [measured value (PV) - set value (SV)] is equal to or
greater than the alert set value, the system is put in an alert status.
The setting range is full-scale.
Measured value (PV)
upper/lower limit deviation alert, within-range alert
2) Lower limit input alert
When the measured value (PV) is equal to or
less than the alert set value, the system is put in
an alert status. The setting range is the same as
the input range.
Measured value (PV)
Alert set value
Time
Alert status
Measured value (PV)
Temperature
set value (SV)
Alert set value
Time
Alert status
MELSEC-Q
Process value (PV)
Non-alert status
[When alert set value is negative]
Measured value (PV)
Non-alert status Alert status
Time
Alert status
Time
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