I have a problem with a 1769-HSC module...
Occasionally the internal counter counts the wrong way !!
I have a rung which asserts the correct setting of the direction bit in the Local:4:O tag, and the picture shows that this does re-assert the direction to the correct one, as the direction changes abruptly (which wouldn't be the case if the machine did actually move in the wrong direction first).
The wiring is correct - differentially connected - encoder A to A0+ and A0-, B to B0+ and B0-, and the HSC modules (3 of them), sit immediately to the right of the CompactLogix power supply, so it's not a distance issue.
Has anyone ever seen this happen ?
As the whole panel is fed from a generator, I'm thinking this may be a supply noise problem, possibly corrupting the data sent to the module, or it is internally being hit with RFI.
The site is currently providing a cleaner mains feed to supply the CompactLogix, and the next step after that may be some form of Line Conditioning...
In the picture I was using manual controls, alternately going forwards, then backwards....
Occasionally the internal counter counts the wrong way !!
I have a rung which asserts the correct setting of the direction bit in the Local:4:O tag, and the picture shows that this does re-assert the direction to the correct one, as the direction changes abruptly (which wouldn't be the case if the machine did actually move in the wrong direction first).
The wiring is correct - differentially connected - encoder A to A0+ and A0-, B to B0+ and B0-, and the HSC modules (3 of them), sit immediately to the right of the CompactLogix power supply, so it's not a distance issue.
Has anyone ever seen this happen ?
As the whole panel is fed from a generator, I'm thinking this may be a supply noise problem, possibly corrupting the data sent to the module, or it is internally being hit with RFI.
The site is currently providing a cleaner mains feed to supply the CompactLogix, and the next step after that may be some form of Line Conditioning...
In the picture I was using manual controls, alternately going forwards, then backwards....