Laser Driver Board problems

Has anybody problem with Laser driver boards on Heidelberg Quickmaster 46-4 plus
Before few years one laser driver board has died and we have to replace.
We buy a new driver board , but its too expencive , about 5000 EUR
before few days died another board on the maschine , not the new one.

 

There are a few of things to check.

1. Do you have enough water in the system. Static pressure should be between 1.5 and 2 bars. When running, it should be between 4.0 and 4.5 bars. The temperature needle should be steady and not bouncing around. If it is bouncing around you have air in the lines.

2. The cooling unit should be no lower than 22 degrees Celsius. If you are turning your cooling unit down below this it causes the electronic boards in the control cabinet, the laser drive modules and the laser carriages themselves to develop condensation. Electronics 101: Water and electricity do not mix.

3. Is the temperature in your shop getting over 23 degrees Celsius? If so, the cooling unit is not able to keep the electronic cabinet cool as well as the ink fountain rollers. This causes the LDM's to over heat. Excessive shop temperatures cause operators to turn down the cooling unit which in turn causes the issues I mentioned in #2.

Checking these things should put an end to your LDM issues.

 

We check all things that you say:
1. We have warer in the system static pressure is 2 bars and wen running is 4.4 bars and we are sure that there is no air in the system .
2. The cooling unit is set on 24 degrees celsius and the temperature in the shop is 25 degrees. We keep temperature stable with Air conditioners and printing is more than perfect.
3. We measure the roller temperature with laser termometer and temperature is 26-27 celsius
I dont think that the problem is in the temperature
We work in this conditions almost 10 years
Thanks

 

I must say your conditions are perfect for running your machine and I commend you.

While you do run your machine in ideal conditions there is obviously no guarantee that the electronics will last forever. LDM's do fail on occasion from use alone just as DVD players, PC or TV's do. (Granted all of those are much less expensive.)

Are the failures on the same unit or from different units? How many years have you run the press without have to replace an LDM?

 

The failtures are on different units and the maschine is almost 9 years old , with about 40 mil. impressions
One electrician came in our shop and we told him about the problem
Ondemand on electrician we remove the two boards , one working board and the nonworking board
Also we give him the old board that we replace before few years
He make some measurments on the boards and he say that the all boards are fine , he think that the problem is in
the some so called UP-DOWN power controler or DOWN-UP power controler
Tomorrow we will continue with work and he think if the problem is in that controler
we can buy only the controler not complete board.
He say that the controler is very cheap about 30-40 EUR

 

I think that Jan exactly can tell you ( if he want to ) what part you need to replace on the LDM board.

 

Who is Jan ???
Do you mean Jan Rozek ???

 

I only know his first name is Jan and he's from Austria.

 

Hi dimaster,
if you are Ognen, just contact me directly when you need any help from me.
rgds
Jan

 

I had a similar problem on mine...one of the boards was bad. But later the same problem came back , so I looked at the connections and the ribbon cables were bad. The coating on the cables had dried up and was cracking toward the end of the connections, which was shorting out several lines.

I would inspect your ribbon cables carefully to see if that may be your problem.

Cheers,

Tracy