Differential Pressure Control ladder logic


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I am needing to control a valve to handle a control valve between a upstream pressure transmitter (upstream of control valve) and a downstream pressure transmitter (downstream of the control valve). I need to have the control valve maintain a certain amount of positive differential pressure and at the same time not allow the downstream pressure to go over a maximum pressure, say 300 psi. Any ideas of how to handle this in ladder logic, with of course a PID loop.

Add a control loop for the downstream pressure. The maximum setpoint of the PID loop being 300 psig or a safe value underneath 300.

Use a remote setpoint from a control loop based on the upstream pressure to generate the downstream setpoint.