Analog Output Question
Analog Output Question
(OP)
I have a system where with a pressure loop that's running three pumps on separate VFD's. I'm limited by the number of analog outputs that I have available on my PLC. Is there a product available that will allow me to output one signal and duplicate it on 3 channels?
Thanks,
Jenkins
Thanks,
Jenkins





RE: Analog Output Question
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Three loop isolators can be placed in series in your PLC output (assuming 4-20 mA PLC output - if voltage output, you'll need to configure as voltage-to-current).
You just need to make sure that the burden of the three isolators is within the capability of the PLC output.
There are many options for signal conditioners/isolators that can do what you want to do. You might even get away with putting all three VFDs analog inputs in series on the same loop.
RE: Analog Output Question
RE: Analog Output Question
RE: Analog Output Question
If you need one, Phoenix Contact has a DIN rail mount signal multiplier:
one 4-20mA input, two 4-20mA outputs which follow the input. The input, both outputs and the power supply (24Vdc) are isolated from each other, so it is an isolator, as well. model MCR-FL-C-UI-2UI-DCI 2814867
Since the input resistance of the module is only 50 ohms, you could probably run one drive and this module in series, and use one of the two outputs for each of the remaining drives.
Dan
RE: Analog Output Question
Mark Hutton