Hi, in our plant we have different AC drives, and with none of them we can use the analog input for reference (4-20ma) and the analog output for current measurement (4 - 20 mA) at the same time because those work, it’s there any recommendation on how we can solve this?
I think just check the VFD configuration parameters, it should work.
Also, check the VFD technical manual and configuration procedures.
What is your VFD model and make?
Also, you need a additional PID controller either a stand-alone hardware unit or a PLC or DCS system’s PID controllers.
we have yaskawa a1000, GE AF-300p11 and Parker ac10, whit the same situation, the only ones that are working fine are some GE and the reason is that they have a option analog card. when we use the analog input alone (for speed reference) works fine, but when we connect the output (for current measurement) at the same time, the reference loop goes to overload (+22mA).
all the drivers are connected to a PLC.