Hi All,
I have a weird situation that I have been unable to figure out. I have a 1769-OFC8 card on my Compact system which is running an L33ER processor and randomly I will lose one of the 4-20 ma outputs on the card.
The card only has two devices wired to it; one is a proportional valve and another is a motor speed input card for a remote motor, both are 4-20 ma.
I have checked the clamp settings and they are 4-20ma limits, so that's right. There are no faults on the module or the processor.
Sometimes, seemingly random in fashion, output 0 on the card just stops outputting (verified with a multimeter). Output 1 still works fine during this time (verified with a multimeter). The only way to "fix" it it so either inhibit/un-inhibit the module or power cycle the system.
The program still shows the output value being sent to the card so I know that it's not a logic issue...plus logically the "fix" wouldn't work if it was.
Any ideas why that happens? A weird random back feed to the card from the device or a loose or shorting wire somewhere are the only things I can think of and I checked for that too.
Thanks!
I have a weird situation that I have been unable to figure out. I have a 1769-OFC8 card on my Compact system which is running an L33ER processor and randomly I will lose one of the 4-20 ma outputs on the card.
The card only has two devices wired to it; one is a proportional valve and another is a motor speed input card for a remote motor, both are 4-20 ma.
I have checked the clamp settings and they are 4-20ma limits, so that's right. There are no faults on the module or the processor.
Sometimes, seemingly random in fashion, output 0 on the card just stops outputting (verified with a multimeter). Output 1 still works fine during this time (verified with a multimeter). The only way to "fix" it it so either inhibit/un-inhibit the module or power cycle the system.
The program still shows the output value being sent to the card so I know that it's not a logic issue...plus logically the "fix" wouldn't work if it was.
Any ideas why that happens? A weird random back feed to the card from the device or a loose or shorting wire somewhere are the only things I can think of and I checked for that too.
Thanks!
