I am using an IFM Efector 4-20mA 2 wire sensor on the MC41 inputs capable of sensing current. Their hookup diagram is what I expected connecting one side of the sensor to high and one side to the sensor port. The input shows a high error when I'm in a neutral state and I can confirm with an ammeter in line that I am sending 4mA to the controller. My best guess is there is too much impedance and internally it is not correcting for it so I tried adding a 5k resistor to ground externally to split the current. It now senses 3.8mA but is no longer accurate over the range.
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