alive15
Member
Good afternoon, I have an Allen Bradley PLC 1768-L43 with one 1769-IQ32 input card and two 1769-OB16 cards (all three on the right side of the processor), along with some other communication cards and power supply module to the left of the processor.
I have an issue where my outputs only send 18V+ out of the card, not the full 24V, despite have 24V going into +VDC on the card (on the 2nd output card). After replacing the 2nd card, the first card began showing the same issue. We replaced the first card. Everything was good, but then the first card started showing this problem again.
This issue occurs intermittently, confusing our techs. We will recycle power a few times to get it back up and going eventually. One of my techs merely pushed the output card to the left a bit to get it fixed one time, so perhaps a connection issue between the cards?
What I need is a way to check the connection between the cards. Is there any way to accomplish this through the PLC or checking any voltages or ohming any pins out on the card? I really don't want to keep swapping parts out and using trial-and-error method.
My only theory is a bad connection between the first input card and the first output card.
Edit: Thanks
I have an issue where my outputs only send 18V+ out of the card, not the full 24V, despite have 24V going into +VDC on the card (on the 2nd output card). After replacing the 2nd card, the first card began showing the same issue. We replaced the first card. Everything was good, but then the first card started showing this problem again.
This issue occurs intermittently, confusing our techs. We will recycle power a few times to get it back up and going eventually. One of my techs merely pushed the output card to the left a bit to get it fixed one time, so perhaps a connection issue between the cards?
What I need is a way to check the connection between the cards. Is there any way to accomplish this through the PLC or checking any voltages or ohming any pins out on the card? I really don't want to keep swapping parts out and using trial-and-error method.
My only theory is a bad connection between the first input card and the first output card.
Edit: Thanks
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