Paper run error 12-10

Hi Everyone,

We are experiencing a paper run error on our QMDI Classic. Whilst printing the press stops suddenly indicating error 12-10 "Paper Travel Monitoring Sensor at delivery 12B6 - sheet lost" (this is according to the fault sheet).

Occasionally there is a lost sheet - sometimes not. However, once the lost sheet is recovered or removed, the 12-10 error does not clear. Even if the press is advanced through one or more complete cycles using the crawl function, the error won't clear. I am also unable to run the press.

If I shut down the press and restart, the error is cleared - only to happen again after a few hundred sheets.

Any advice / help would be greatly appreciated.

Regards

Shawn

 

Have you opened the side doors and accessed the sensor? clean and look to see if there may be a sheet or piece of paper flopping around in there. Sometimes they hide just out of sensor range and begin moving around as paper passes over them triggering another lost sheet.

I should also add you may want to look at the gripper (rubber pads) on the gripper bars at the delivery. Occasionally they do come off and/or barely catch the lead edge of the sheet in the grippers, sometimes loosing the sheet in transfer.

 

Bill is correct on those items, in my experience dust and paper scraps have been the culprit. Also make sure you run Short grain cover stock if you are running with cover stock, long grain does not curve around the delivery cage and sets the sensor off. If you have to run long grain cover stock turn off S18.

 

Hi Bill / Paul,

Thank you both for our feedback. I have checked that the paper path is free of any loose sheets or any other scrap pieces that my have become trapped inside the press. Unfortunately I have found nothing. The sensor eye appears clean and dust free. Thecable is attached properly and the LED on top of the sensor flashes as normal when the eye is triggered.

The problem I am still experiencing is that the 12-10 error won't clear even after a lost sheet is removed from the press. Normally, pressing S11 and the cancel button sould clear this error but it won't clear. The error only clears when the press is turned off and switched on again. Then when the error occurs again, the same thing happens.

All other errors clear as normal once the situation has been rectified except for the 12-10 error. Could it have something to do with the sensor/eye in the feeder? Also - which board controls these two sensors viz. 12B6 and the feeder sensor (double sheet detector / front edge detector) - Sorry I know i am not using the correct terminology.

Please - any advice or help would be most welcomed!

Kind Regards

Shawn

 

Sorry Paul,

I forgot to mention - this is occuring with normal 90gsm paper stock which is long grain. I ran the same paper through the press last week with no problems - the error only started last Friday.

Thanks again.

 

It sounds as if the sensor itself may be failing. There is a way you can check it. The signal wire from 12B6 goes to the SVK board, plug X4 Pin 5. If you use a volt meter the is pin will read "0" volts with no paper in front of the sensor and 24 volts with the sensor blocked.

If there is no paper in front of it and it is reading 24 volts the sensor is bad.

 

Hi Paul,

Many thanks for that. I will definitely try that.
Is it possible to run the press with the sensor turned off (S18) - I suppose the only hassle would be not knowing when we really lose a sheet.

Thanks again for your reply.

 

Hi Paul / Bill,

I managed to solve the 12-10 problem. It was a bad connection on the cable that connects to the sensor. I sprayed it with some switch cleaner and this seems to have solved the problem. There is however something curious about the sensor 12B6 though. The green LED on top stays lit when there is no paper infront of the sensor and turns off when there is. The sensor on our other DI works opposite to this one.

Also - the sensor gives a reading of 22.8 volts with no paper in front of it and 0 volts when it is blocked. That is also the reverse of what Paul said to check for. Is it possible that the sensor may be incorrectly wired?

Thanks again for the help!

 

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