eight_bools
Lifetime Supporting Member
Been struggling to wrap my head around this all day, maybe someone else has an idea.
I've got a pressure sensor connected to a 1771-IFE analog input card. The signal is bouncing around, both in the PLC displayed value and measured in series with a fluke 773.
When I check the sensor on its own, its giving a stable output, around 5.51mA. When I simulate a current directly to the input card, it reads a stable value matching the Fluke output. When I connect the sensor to the PLC it starts to bounce around.
I'm currently trying to find another analog sensor I can test this with, I checked both ends of the cable and have the same result. I drew up some photos, hopefully they help.
Forgot to add that there are two inputs, the first two channels on the card that are behaving like this. All the other 6 inputs are working normally. I checked the input by moving the wire to a known good input and it is doing the same thing. Both of these are connected to devices that are wired out of the same remote panel.
I've got a pressure sensor connected to a 1771-IFE analog input card. The signal is bouncing around, both in the PLC displayed value and measured in series with a fluke 773.
When I check the sensor on its own, its giving a stable output, around 5.51mA. When I simulate a current directly to the input card, it reads a stable value matching the Fluke output. When I connect the sensor to the PLC it starts to bounce around.
I'm currently trying to find another analog sensor I can test this with, I checked both ends of the cable and have the same result. I drew up some photos, hopefully they help.
Forgot to add that there are two inputs, the first two channels on the card that are behaving like this. All the other 6 inputs are working normally. I checked the input by moving the wire to a known good input and it is doing the same thing. Both of these are connected to devices that are wired out of the same remote panel.
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