Direct and reverse action of control valves
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Which parameters control whether the control valve acts in a positive manner or in a negative manner. We got the flow control valves on our device completely wrong; they won’t switch to automatic mode at all. When using cascade control, should the control valve also act in the opposite direction? :)
The positive and negative actions of the regulator require consideration of the following factors； 1. The forward and reverse action of the control circuit. 2. The air-on/air-off operation and forward/reverse action of the actuator. Based on the above, the forward and reverse action of the regulator is determined
This is adjusted according to the requirements of the process
The forward and reverse action design of the flow control valve is reversed; this can be corrected through the settings of the instrument. After making this adjustment, the cascade control should no longer need to be altered.