Zero setting values on QMDI +

Hi,

Anybody got any ideas as to why the zero factory settings (in service via the keyboard) is not working on the diode calibration settings display but is working on the register settings display.

Thanks.

 

Because they did not put in any. When the diodes were calibrated at the factory the power settings typically were not saved as there is no true zero for the diodes. Each diode has a base setting written on it which would be input. Over time with a customer replacing diodes and changing values to make them even, going back to a factory zero, if there was one, would just put the diodes all over the place and you would have to reset them from scratch all the same.

What the factory did do, is send along with the press a "factory" footprint 3.5 floppy that had the diode settings on it which was made just before the machine was packaged for shipment. It was located in a zip lock bag in the console along with the electrical diagrams. Typically the customer either lost this disc or made footprints over it.

 

Hi Paul,

So if i read what you are saying correctly, is insert the factory footprint disc and re-set the footprint via that disc or make a new footprint onto that disc and that will allow me to zero the diode readings.

Thanks

 

The factory footprint disc will set all the diodes back to whatever power values they were at prior to leaving the factory. If there were not many changes made, which I find highly unlikely, you will be relatively close. Making a new footprint will only save the power levels the diodes are currently at.

The factory zero settings you are talking about for skew, register, align_B, etc. are not truly a "Zero" per se. They are a zero setting based on what it took to get those specific imaging heads aligned to that machine. In most instances the imaging heads themselves will stay with the machine for the life of the press so those values are always kept on the hard drive to retrieve when you go into the service functions to re "zero" the press. The Diodes on the otherhand as I mentioned previously would get changed by the customer over time so there was no reason to save a "Zero" for them.

My guess is that you have replaced and imaging head complete and are trying to get the diodes to a starting point?

 

Hi Paul,

No, what exactly is happening is when i am trying to adjust the laser power on say for instance PU4 laser #8 , it is currently reading say 120 in the info screen which is fine, now if i adjust that particular diode by say -30 and ok and then re-image and then check the info screen the reading is still saying 120 when it should say 90 and also the diode power is not moving.

All the diodes are working ok and there isn't an issue with any of the laser drive modules.

All the figures in the set diode level screen are all over the place and i just wanted to zero everything to make it easier for the customer, which is what the new zero levels button is not allowing me to do.

Also on the same machine which i don't think is related, the screen is freezing after an imaging when its trying to send over the ink values to the ducts, keys 1 - 8 will alter on all units but 9 -12 stay closed (if starting from a shut down position) the only way to get going again is to re-boot the machine.

Regards.

 

Out of curiosity have you tried swapping that laser diode with another one? Also are you on a Pro or a Plus machine?

A couple of things can be happening with the ink profiles locking up. The first one I always check for on a Classic or Plus machine is if there are too many saved ink profiles. The press uses the hard drive as virtual memory, once the storage space starts getting used up it can't process information as quickly. The CPC functions require the most memory as you can imagine. If there are over 75 ink profiles stored the CPC starts locking up. Furthermore it will not let you delete them through the GUI any longer and you will have to go into DOS to do so.

The other thing that causes issues is if a command is sent from the GUI to the ink keys instructing them to move. Once the command is sent the PC keeps polling the press to see if the keys have reached the values requested, if they do not move within a certain time period the PC times out and locks up. The typical reason for this to happen on a Plus or Pro with 12 ink keys is the ink keys have a large amount of ink under them preventing them from opening. This is why they can reach zero but not go up. Also it is usually the outside keys that have the most ink under them as most people wipe the ink from one end of the ink keys to the other, inadvertantly pushing it under the ink keys on one end. (If you ask the operator which way he wipes the fountain you will know which keys are the worst.)

The last thing that can cause all this but is unlikely is a corrupted hard drive with crosslinked files.

 

Hi Paul,

It's a plus.