Fan buzz progressive dynamics 4645-
I've installed two of these converters (orig and replacement). Both exhibit buzzing variable speed fans.
1. Nothing wrong with the fans themselves-when they operate, they're quiet.
2. Occurs when converter is producing about 10 amps and fans are cycling off and on.
3. Occurs when the fans cycle off, and have stopped turning.
4. At that point fans are acting like a speaker-producing approx 60 cycle buzz.
Evidently there is still some power applied to fans, even when not turning. That power is evidently not well filtered.
The fans are 12V DC Sunon computer fans. Both converters were functionally normal.
Wondering if you can think of any electrical solutions? How about a filter capacitor across the fans? If so what value (sounds like about 60 HZ noise)?
Thanls_
1. Nothing wrong with the fans themselves-when they operate, they're quiet.
2. Occurs when converter is producing about 10 amps and fans are cycling off and on.
3. Occurs when the fans cycle off, and have stopped turning.
4. At that point fans are acting like a speaker-producing approx 60 cycle buzz.
Evidently there is still some power applied to fans, even when not turning. That power is evidently not well filtered.
The fans are 12V DC Sunon computer fans. Both converters were functionally normal.
Wondering if you can think of any electrical solutions? How about a filter capacitor across the fans? If so what value (sounds like about 60 HZ noise)?
Thanls_
