MicroLogix 1400 HSC

I am testing a program using a 1766-L32BXB
I have a single ended Encoder attached to I:0/0 with a HSC:0 set up.
the Encoder is on a 6" Diameter roll with paper driving it and a prox switch on the stand the roll us unwinding from give a pulse each rotation.
My problem is the count is a little erratic, although it should keep counting down as the roll unwinds which it does for the most part I don't seem to have any consistency in the number flow and I also get some counts that actually go back up a few pulses from the previous count.
I am going to see if I am getting slippage of the paper but that should make the count be a lot less which possibly could make the next one greater.
Being new the the HSC in Micrologix I am wondering if the problem is in my program. I have tried just having the counter and a reset with no other program yet I still see the problem.
I am using an input from the prox through a [ONS] to MOV HSC:0 to L9:0
and a RAC to reset. Could there be scan delay on the reset and should I set it up with the reset as an input (I:0/5)
Thanks for any advice.

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here is program, last 2 rungs I added fifo to see encoder counts

Is the reset through input I:0/2 for HSC:0 faster than the RAC in a program

Also- check what your hardware input filters are set to. IIRC, the default is 8ms which is crazy slow for a HSC application.

I have them set at min 5us

Use the hardware reset if you can but it can be pretty awful using a single ended reset signal if there is any noise on the system. All you need is one ****ty DC contactor/brake and the thing will be resetting all over the place.

edit: if your count direction is erratic it might even be a problem with the encoder. In the bad old days, sometimes a disk in the encoder would drift out of alignment and the shape of the quadrature would get messed up. Have you put a scope on it to check the channel phasing?

I noticed that your program has the Left Prox OR the Right Prox switch resetting the HSC. Is it possible that one is true slightly before the other? If that was the case you would get a reset of the HSC then a some time later you would get another reset. That would throw your counts off.
Just a thought.

Only one roll is running at a time. While its running they are setting up the next roll to run and possibly could fire the other. I intended to add rungs to tell it which roll is running to prevent this later if I could get the count to work. I noticed yesterday while running I think the roll is slipping on the chuck and thus throwing the prox off in relation to the roll.
Maintenance said they will change the grips in the chuck for me to retest. Thanks for the input.