I post this instructable for those who are sick of the extreme high price for spare parts that are not suppose to fail in the first place. In this case a friend who ownes a printing workshop called me to troubleshoot his Roland Versacam VP540 printer/plotter.
The machine did not turn on after several sudden stop during a printjob. First i checked the power supply.... 41 volts DC no problem there. Replaced the servo board.... no result. Then i did what is one of the most common probems in failing equipment. Replace major capacitors.
This problem is verry common in a large scale of equipment like flatscreen TV's, computers, fitness equip. audio equip. etc. The cap don't always show leaking or a fysical defect.
If one capacitor shows leaking or is not completely flat at the top..... replace it. Replace all large caps. If one goes bad its verry likely that the rest are not optimal anyway. These are not expensive components so don't try to save money.... otherwise you'l get frustration in stead.
Its also wise to replace the cap with a higher voltage then the original one used by the manufacturer.
On the board the caps shown by the arrows are 220 mF 50 volts i replaced the caps with 470 MF 63 volts.
The repair costs where about 3,- dollars and and 15 minutes of my time, a repacement board is about 1800,- dollars.
I'll try to post more repair tips on a wide range of failing electronics.