BAJ
Member
I've got a weird one. I'm helping a customer with a CompactLogix system. They have a 5069-IB16 with several spare inputs and we are trying to add a dry-contact pressure switch as an input, but the 5069-IB16 is not registering the 24vdc that is passed to the input terminal as "on", either via the LED on the front or in Logix5k.
The pressure switch is new, mounted inside the same panel as the 5069-IB16. I confirmed the wiring, confirmed the N.O. contacts are working with my ohm meter when I cycle air on and off, confirmed the 24vdc is making it to the switch, confirmed the 24vdc is making it to the 5069-IB16. I tried a couple other spare inputs, same result.
I tried jumping the 24vdc direct to the 5069 terminal, then it lights up and registers. I get 23.8vdc everywhere I measure, so there is no voltage drop in the system. If I jump 24vdc supply to the input WHILE the pressure switch is wired to the same, the LED comes on and will stay on when I remove the 24vdc source jumper. However when the pressure switch cycles off-on, the 5069-IB16 fails to register the 23.8vdc on it's terminals coming through the pressure switch.
I tried running all new wiring to the switch, same result.
The DMM I have is a Fluke, but a less expensive one. It measures 0.2 ohms across the pressure switch contacts when they are closed, OL when they are open. I also measure 6mA going through the pressure switch when it's closed and wired to the 5069-IB16 module (multiple spare inputs tried), which is the exact value specified in the manual as nominal for the 5069-IB16.
Anybody every seen anything like this? I'm at a loss.
Thanks,
-Brad
The pressure switch is new, mounted inside the same panel as the 5069-IB16. I confirmed the wiring, confirmed the N.O. contacts are working with my ohm meter when I cycle air on and off, confirmed the 24vdc is making it to the switch, confirmed the 24vdc is making it to the 5069-IB16. I tried a couple other spare inputs, same result.
I tried jumping the 24vdc direct to the 5069 terminal, then it lights up and registers. I get 23.8vdc everywhere I measure, so there is no voltage drop in the system. If I jump 24vdc supply to the input WHILE the pressure switch is wired to the same, the LED comes on and will stay on when I remove the 24vdc source jumper. However when the pressure switch cycles off-on, the 5069-IB16 fails to register the 23.8vdc on it's terminals coming through the pressure switch.
I tried running all new wiring to the switch, same result.
The DMM I have is a Fluke, but a less expensive one. It measures 0.2 ohms across the pressure switch contacts when they are closed, OL when they are open. I also measure 6mA going through the pressure switch when it's closed and wired to the 5069-IB16 module (multiple spare inputs tried), which is the exact value specified in the manual as nominal for the 5069-IB16.
Anybody every seen anything like this? I'm at a loss.
Thanks,
-Brad
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