Intermittent encoder reading

[ijan]

Hi all...

I have a problem with rotary encoder reading and it's already occured several time. the problem is encoder reading working intermittent...i never can figure out what caused this problem. the strange thing is the scale of encoder in NI Max become zero by itself. I thought the problem is on the operating system because NI Max database on this PC already crash 2 times and the whole channels and task configuration corrupt. I solved this with re installing NI Max without knowing the caused of the problem. And now the encoder reading intermittent and i'm still struggling to find the problem. I use NI Max 9.4...

Please help?

Thank you

[Prickly_Pear]

This sounds like a strange problem. Usually reinstalling MAX and reseting the database will solve problems like this.

Is the only problem that the scale turns to zero or is there another problem? When does it turn to zero--when you save the scale, when you use the encoder, or some other time?

Jeremy P.

[ijan]

Yes its very strange problem. Reinstalling MAX and resetting the database will solved the problem but i don't wan't to do that again and again everytime its occured. I just need to know what is cause the problem. right now the problem is the encoder reading intermittent, the scale is ok now. i'm not sure if the problem comes from the daq or the software, i suspect the problem is come from the OS itself i mean the ms windows which affect to ni software. I don't know when the scale turn to zero, what i know is the software suddenly giving intermittent encoder reading. 

Let me clear this problem so maybe some body can help...

the intermittent reading and scale turn to zero is different problem. When the scale turn to zero the encoder not reading at all but after entering the correct scale value the problem solved. what i'm struggling is the intermittent reading which i'm still can't figure out why and how to solve it.

Thank you

[Prickly_Pear]

The reason that the first problem happened was that there was a corruption in the MAX database. Corruptions can happen for a lot of reasons. They often have to do with improper installation of hardware and hardware drivers. By reseting the database, you erased the corruption. I believe that when you reset the database it also reset your scale value to zero. Have you experienced a problem with the scale since you entered the correct value again?

Also, could you describe the problem that you are having with your encoder reading? Was it working before you reset the MAX database? What hardware are you using? Are you looking at the data in LabVIEW or some other software?  What do you mean that the readings are "intermittent"? Do you mean that the encoder misses a lot of pulses?

Jeremy P.

[ijan]

First thank you for your help....

For the encoder i use NI 9215 and i'm looking the data using labview. This problem alread occured 3 times, everytime it happened i reinstalled Max to solve the problem and now it happen again. Actually i can reinstall Max to solve it but i really wonder why it happen?

I have a question can it be solved only by resetting NI Max Database and restore the task and channels from previous backup? if it does then it will be a faster solution.

In another place i have another encoder problem too which not reaading at all. Is it possible that a corrupt database could cause this problem. The encoder is attached to a motion devices (using PXI and PCI). Again if the problem is caused by corrupt database can i solve it with reset and restore it? i already export the task , channel and ni motion configuration.

Thank you

[Prickly_Pear]

You are correct that sometimes the corruption can be fixed by reseting the MAX configuration database and restoring the database from a backup. It is good to try that. However, if the problem is with MAX itself and not just the database then you will have to try to repair the installation of MAX.

There are many reasons why your other encoder might not be working. Does it show up correctly in MAX and Windows Device Manager? You mentioned that this is using a PXI chassis. What PXI card and chassis are you using exactly? It is possible that this needs another driver besides DAQmx. Is it able to pass a self test in MAX? Do the other functions of the card work besides the encoder? It is possible that the problem could have something do to with the corruption in MAX, or there is a problem with the driver, or it could be that the encoder is broken.

It might be a good idea to make another thread to talk about the problem with the other encoder not reading at all. More people respond to new posts because they show up at the top of the forum. It would be good for you to include exactly what hardware you are using, whether or not the device shows up in Windows Device Manager, whether or not it shows up in MAX, whether or not it passes a self test, and any other information you think would be helpful..

Good luck with all of this. I hope that you are able to get it working soon.

Jeremy P.