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Allen Bradley 4-20 mA input signal

Allen Bradley 4-20 mA input signal

Allen Bradley 4-20 mA input signal

(OP)
Is it possible to set up my PID in RS Logix 500 for a 4-20 mA input signal. I've done it a couple of times just using thermocouple inputs but know have a 4-20 mA Omega Infrared Thermometer/Transmitter. I'll appreciate any help.

RE: Allen Bradley 4-20 mA input signal

In general, if your device can accept a voltage input, you can use a 4-20 mA signal by simply putting a precision resistor across the input terminals to develop an appropriate voltage proportional to the signal current.

The resistor size should generate enough voltage a 20 mA to give you reasonable input range, but should also be kept as small as practical to reduce burden on the 4-20 mA transmitter.  A 500 ohm resistor will 10V out at 20 mA and will generally work if you don't have too many other devices in series with the resistor.  A 250 ohom resistor will provide 5 volts and this is generally adequate for most controllers.  

RE: Allen Bradley 4-20 mA input signal

(OP)
I should have no problem working the input signal since I placed a 16 channel analog current input on my SLC, but the thing I don't know is how to set up the PID to work by using the 4-20 mA input, like I said I have worked it before using Thermocouple signals, but wouldn't know if I could set it up alike.

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