Control Logix 1756-IF16 Analog Input with Isolators


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Is it possible to connect all channels of the allen bradley 1756-IF16 with analog input via intrinsic safe isolator like MTL 5041? All of my signals are intrinsic safe and I have isolators (not barriers) installed inside the PLC cabinet. I have to wire the analog signal from the isolator to 1756-IF16.

The wiring drawing of the card 1756-IF16 doesn't show the 4 wire transmitter connection (isolators are sourcing the 4-20mA). The wiring says the card is single ended (i think it means non-isolated).
So will it be possible to connect the current (4-20mA) signal from intrinsic safe isolator to 1756-IF16, if yes please explain how.

Hi Kevin

Thanks for the reply. I shouldn't have said 4 wire. all of my transmitters are 2 wire, powered by the intrinsic safe isolator. So basically the loops behave like 4 wire but not 4 wire and the analog signal from the isolator (sourcing from the isolator) to be connected to IF16.

All of the isolators and PLC powered from the same 24VDC power supply. Is there going to be any issue.