screen 8000 burning issue

[heitechpro]

i have a screen 8000 ctp. its laser timer shows around 4500hrs of usage. i m facing a burning problem on the plate. when i expose plates at 800rpm and 85% light, the image is not visible on the plate before been processed thus heavily relying on the developer. well image does appears up after processing but the developer only lasts around 50-70 plates. after this scumming appears on the plate and u have to develop it twice even when running the processor at the slowest speed. but when i reduce the speed to 500 rpm and light value 85% the image is visible but not to that extent before processing and works alright with the old developer as well thus increasing the recording time on the machine. can someone leme know what is actually wrong. i have tried cleaning the lens and the diode glass twice and never helped much.

[Dolev4press]

Hi there, Main problem of Yours is wrong plate calibration.
Depending on the plate and developer You use, You must calibrate clear point of the plate.
Please let me know what plates You use. I had a lot of plate types used and know many params.
Also if You use Ipagsa or any other Spanish plate You must set power to 100% on 800rpm.
In thermal technology You can't overburn plate!
If You have any questions in advance please contact me.
Andrey.

[heitechpro]

hi, thanx for replying to my message. well if i increase the light value more than 85%, an error appears as ''Some LDs cant be calibrated to target enough power. Contact our agency to replace them''. i m using Kodak Capricron GT plates.

[Dolev4press]

HI again.
In this case You need to replace some diodes or if all of LD values are low just clean the optics inside the head.
It's no any other exit from this situation.
If I can help, just ask.
Andrey.

[heitechpro]

thanx for the quick reply. u think replacing some diodes instead of all would increase the light value?? what if all of them are weak

[Dolev4press]

I think it's not possible. Just make laser calibration, then find IopD-Iop value and give me know what are they.
Andrey.
Please contact me on dolev4press@gmail.com