compact logix and encoder count

Have a machine we recieved for evaluation that is from Italy that has a compact logix 1769-L24er plc. It has a high speed counter that has a encoder connected and is using this encoder count to determine when to turn on and operate motors, cylinders etc as product moves through the machine. It the program they are taking the actual counter0currentcount and moving that into another tag MainMotorPosition. What we have found if that for some reason you stop the machine and turn the power off and the encoder has not make a complete revolution and reset its count, the value in the counter0currentcount will go to zero. The machine is designed so that if it is stopped during the cycle you can resume the cycle and finish it and all the cams work as they should, but if power is turned off you loose the counter0currentcount.
The folks that designed the machine are coming it to take care of this as well as some other issues we have found. Based on experience from folks on this site is there a memory retentive area that the counter0currentcount value can be moved into or a way to set that up so that when you turn the power off and on it does not loose the count value.
Thanks

Maintain your own counter in the program, by using the difference in counter module counts each scan. Add that to an internal DINT.

Now you have a counter that retains its value through power cycles.

Thanks for the reply.

has anyone used a ethernet encoder? I was talking to my ab rep on the phone and he said that it may be possible to use a ethernet allen bradley absolute encoder. Never tried this and wondering if anyone has and if so what did you think?
We are still at the position that if requested the machine manufacuturer would have to change the incremental encoder they have feeding into the high speed counter input to a absolute type.
Thanks

I put an Allen-Bradley 842E-S Ethernet encoder on the project we're finishing up now. I'm not using it for motor position, but I have it attached to an axis as a hydraulic cylinder bends a part, the encoder measures the table as it rotates up and reports the bend angle. It gives me absolute position data, so it doesn't lose it's position on shutdown. It's a single urn instead of multi-turn, which works for me, but there's a multi-turn option if you need it. MUCH more accurate than I need, but I'm a big fan so far. Much better than how we were doing this before. If there's any info I can provide to help you, let me know.

Yes, I've used the AB Ethernet encoders in one particular application. They work fine, but I wouldn't deploy them universally. I can swap any old quadrature encoder with any other, whatever is on the shelf. Using the Ethernet encoder ties you to only a single source.

thanks
I got a copy of the changes the manufacturer said he is looking at making so the encoder counts do not go away when you turn the power on and off. I will try and explain and post some screen shots. I have looked it over but have to admit that most of my experience is with the micrologixs so do not quite understand the code. Could someone take a look that has a whole lot more experience than i do and if possible explain how this would work any different.
Thanks