Pressure sender wiring question

[Richard Connell]

I can’t get my head around what should be an easy question…
I have a MH bottle which uses a 4-20mA sender to drive the pressure gauge on the panel. So far so good.
I know I could also put a resistor in parallel to ground at the GEA to convert this to a voltage to read the tank pressure using one of my spare GP inputs. I want to do this because I like data and this way I’ll be able to track usage. Also it’s easy.
My question is can I do both at the same time? So two gauges in series off the same current loop sender. One current based and one current but converted to voltage at the receiver - or is this going to lead to two incorrect readings?
Thanks!

 

[Bill.Peyton]

I would think you could put a 10K pull-down resistor to ground at the GEA GP input to set the input to zero, and measure the voltage drop at the red lead of the O2 pressure sending unit. Create a custom scale for the GP input.

 

[Richard Connell]

Thanks bill.
Yeah there’s no problem measuring it this way in Volts at the GEA. But what happens if im concurrently measuring the mA at that same lead on a different receiver.

 

[Bill.Peyton]

As I recall, GEA GP inputs are high impedance and should not put a load on the other instrument. In reviewing the Installation Manual, you should not need a pull down resistor.