Encoder problem query

I have a 1000 PPR encoder existing, this rests upon my product. I need the 1000 PPR for one part of the manufacturing process(plc controled print). The problem that is created is that sometimes my product "stutters" as it is being made(simpler term: goes forward and backward as like a vibration). This causes the problem in the second part of manufacturing process, (I know that the encoder works with light thru etched openings), and here lies the problem, the "stuttering" aspect "wiggles" this opening in and out of the light path but it may not really be a full opening movement. I would be far better off using just a 100PPR encoder but thus I would not get proper print. What can I use that could give me a solution? Some thing that would take a 100PPR and change it to 1000PPR??

Use a 'quadrature' encoder with a suitable counter. This will detect both forward and backward movements and keep the actual position correct. The 'quadrature' encoder has two outputs for position, 'A' and 'B'. Is the encoder going to a PLC? Investigate the abilities of the PLC to handel this type of signal, either with the hardware you have,or possibly with an add-on module.

If I understand correctly, your problem is excess counts due to the product moving backward occasionally. The simplest way to eliminate this is to use a quadrature encoder (and connect it to a device that can accomodate quadrature counting).

A quadrature encoder delivers two pulse trains (channels A and B) that are 90 degrees out of phase with each other. The device connected to the encoder watches each transition (off-to-on and on-to-off) of each channel. As long as each successive transition is from a different channel (A On, B On, A Off, B Off, etc), the counts continue to accumulate in the same direction. When two successive transitions are from the same channel (A ON, A Off) the direction is assumed to have reversed and the counts accumulate in the opposite direction.

I am using the "A" pulse to my printer and the "B" pulse to my length count, should I be using something which takes these 2 signals and interperts them differently before sending them to the "ends"

He stated forward and backwards but I think the material has a "wave" or "ripple effect" (he said vibration/stutter) that may be making the encoder and material separate and either lose counts or freewheel too fast and add bad counts.

I have a 1000 PPR encoder existing, this rests upon my product.

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That statement leads me to think its an encoder with a wheel.

Sounds more like issues with tension control.

yes it is an encoder with a wheel

the product is moving a slow rate 12in/min so no bounce or slipage

If your A and B channels are going to two different devices, then you're not taking advantage of the ability of a quadrature decoder to differentiate between forward and backward motion. If that's the root cause of your problem, then you should should connect both channels to a device that is capable of properly interpreting the signals.

Check to see if your device for 'length count' is capable of accepting a quadrature signal. (Note: if it does and upon connecting you see negative movement just swap the A and B lines.) If the encoder has enough drive you may be able to also connect one of the lines to the printer as you are doing now.