Reverse/Forward Action Select Function; Rfb Limiter Function; Sensor Compensation Function - Mitsubishi Electric MELSEC-Q Series User Manual

3 SPECIFICATIONS

3.2.3 Reverse/forward action select function

3.2.4 RFB limiter function

3.2.5 Sensor compensation function

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With the Q62HLC, "reverse action" or "forward action" can be selected to perform the
PID operations.
(1) Default setting
The default is set to "reverse action".
To perform PID operations with the forward action, set "forward action" in
Forward/reverse action setting (buffer memory address: 54, 86).
(2) Control details
(a) Reverse action: The manipulated value decreases as the measured value
(b) Forward action: The manipulated value increases as the measured value
REMARKS
The Q62HLC does not support heating/cooling control. If a target device is
controlled using two channels of the Q62HLC, the temperature does not
stabilize.
(1) RFB (reset feed back) limiter function
The RFB limiter function prevents the PID operation result (manipulated value
(MV)) from exceeding the range by the integral control action when a deviation
continues for a long time.
If the PID operation result exceeds the upper/lower output limiter value, this
function feeds back the exceeded value to the integral value, and holds the PID
operation result within the specified range.
Setting is not necessary as the RFB limiter function is automatically operated at
PID control execution.
(1) Sensor compensation function
The sensor compensation function compensates the difference between the
measured value and actual temperature, humidity, pressure, and flow rate
caused by measurement conditions.
(2) Sensor compensation value setting
When there is a difference between the measured and actual temperature, set a
temperature (-500.0 to 500.0 ) in Sensor compensation value setting (buffer
memory: 45, 77). When there is a difference between the measured and actual
humidity, pressure, or flow rate, set a full-scale percentage (-50.00 to 50.00%) in
Sensor compensation value setting (buffer memory: 45, 77).
For example, when there is a 0.3V deviation with the input range 0 to 10V, set 3%
(0.3÷10 100= 3%) because the full-scale is 10V. (Set 300 in the corresponding
buffer memory area.)
increases. This action is effective for heating control to
increase temperature.
increases. This action is effective for cooling control to
decrease temperature.
MELSEC-Q
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