VFD Capability Question

I have got a rheostat wired in to the analog input to adjust the speed of the VFD and now I want to add a flow transmitter to monitor the flow. The problem is the drive only has one analog input. Can I do this?


I am using a Micromaster VFD.

Thanks,

T.S

Are you trying to set up a PID loop?

What brand VFD and family is the drive? IE: Magnatek GPD502, Allen Bradley 1336.

If you only have one analog input to the drive, it is not capable of doing internal PID and you need and external PID control PCB.

Leadfoot said:

Are you trying to set up a PID loop?

What brand VFD and family is the drive? IE: Magnatek GPD502, Allen Bradley 1336.

If you only have one analog input to the drive, it is not capable of doing internal PID and you need and external PID control PCB.

Click to expand...

Yes we are tring to set up a PID control the rheostat will cause the disturbance and the flow transmitter will detect the disturbance and we want the VFD to correct this change.

The VFD is a early addition of Siemens Micromaster drive. We are tring to control the speed of a motor with a flow transmitter while also tring to adjust the speed with rheostat.

Thanks for your response.

T.S

If the drive does not have built in PID capabilities, it could have 10 analog inputs and not help you out.

You need to get a PID control PCB or MODULE and have it then control the VFD speed.

There are an abundance of Relay looking PID controls that plug into 8 or 11 pin sockets that your Potentiometer and flow control feed and it then calculated the necessary VFD speed and signals the VFD to do so. It is a bit of a throw back, but not every drive has built in PID.

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