Help: FAN-outs = faulty. Suspect damaged FETs, need replacing?
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So... I believe I have a faulty fan that over taxed the FET that it was on the past number of years; I feel silly that I didn't consider it bad to keep using since it still powers on and blows hard... I don't know why it's shorting out these FETs?
So I tested it for a bit on FAN0... then I think I heard a lil pop, and the fan stopped... then I tried a new fan on it... and it's only blowing at 20% or so even set to max. when I looked at the FETs, I could swear that 0 had a dot on it, but not 1 or 2, then 2 had a dot on it after the popping sound... least I'm pretty sure there was a physical change.
SOOO I'm with out of cooler fans it seems... I need to replace these FETs... Can someone tell me where to order new ones?... and also note if this problem could be worse than just loosing those?
ALSO! as a work around is it possible to use a different set of pins to power a cooler fan? I have spare heater and extruder slots free.
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I've got a similar problem, except none of my fans are working. I'm considering just getting a bunch of cheap 24v power supplies if I can't fix the fan headers.
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@ottobawt the part numbers are here:
https://duet3d.dozuki.com/Wiki/Connector_and_spare_part_numbers#Section_Fan_mosfet -
I ordered a few of both the AO3400A and AOSS32334C, last night, thanks.
Do you know which one is "better" ? more robust/reliable?
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@ottobawt the AOSS32334C is rated at slightly higher current, but they are both rated a lot higher than the 2.5A we rate the FAN outputs to so either is fine to be used and wont blow in normal use. They will probably both blow in a failure where the output is shorted to ground due to wiring or a failed fan. The situation where 5.8A is passing (which in theory would blow the AO3400A but not the AOSS32334C is less likely, and is also a higher current that the headers, pins etc are rated for.
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Thank you for the explanation.
I do believe I found the gremlin that started this, seemed the power wires to the fan's PCB start to fray and looked possible that they were shorting... but I tossed it just in case it was something else.
I sure hope this repair isn't too tricky.
