mcheavens

I could not test the ESR, just the capacitance. I replaced them all while I was in there. I have another failed one that I will work on in the next few weeks (It is at another location). My plan was to start with C7 remove and test/replace first on that unit. - I also plan on drilling a few holes around the device to lower the internal temperature. FYI, I also tried to replace the serial interface board and put it on a USB version that I had sitting around. (the daughter board location and header was the same) - That will NOT work! The USB version has different software in the mainboard. (But the mainboard looks more robust). Mark

I had two dead PLM's. Both failed in similar fashions. They became unstable and would not communicate. LED's were very dim. Rebooting would fix them for a short period of time that got shorter as time went on. Replaced the five capacitors listed in this thread. C3 - 6.8uF 250v with digikey 491-4771-1-nd 10uF 400v C7 and C13 - 10uF 35v with digikey 493-5976-ND 10uF 50v C8 10uF 16v with digikey 493-10390-1-nd 10uF 16v C11 100uF 25v with digikey 493-3276-nd 100uF 25v As I removed them I tested each cap. On BOTH PLM's just repaired (and now working) the only caps not within specs were C7 On PLM#1 that would not work at all anymore the value was now 3.6uF. One my second one that would work for a few hours at a time was 6.04uF Hope this helps. In the future I might just try to replace C7, and replace it with a higher voltage rated cap. Mark