Replace fuse for broken fans

droftarts

And check your fan wiring connections before turning it on, once you put a new fuse in!

Ian

jontek2

I've now replaced the blown fuse with a generic mini fuse 2A and the fans are now working again - thanks everybody!

May i suggest to the mods that you change the title of this thread to "Replace fuse for broken fans" or something. It may help somebody else in the future.

TLAS

Also a shout out to the electrical designers of the cards - thanks for putting this in!

The fuses are pretty recent addition and I’ve blown them out a good 1/2 dozen times now (got a huge pack off of Amazon...). So very grateful to replace the fuse over a dead board.

Thanks!

TLAS

+1....

Make that 7 now.

Upping the fuse to 15 Amps based on this thread:
https://forum.duet3d.com/topic/1925/max-hot-end-heater-current?_=1574893763955

If anyone cares, using PTC heaters may cause unexpected blown fuses. The resistance (and thus current) varies with temperature. As the heater gets over a specific temperature (about 60C effective operation) resistance rapidly increases cutting off power to the heater until it cools down. Great for safety.

Downside is that if the heater is cold, the resistance is even lower than normal and can result in a sudden onrush of current before it starts to warm up. Enough to cause a standard 7.5A fuse to blow.

pipersw

@TLAS it's fan fuse here, not the bed fuse so 1A is good

TLAS

@pipersw

Blown a few of those too.

Tornado-Like Fans - pulls ~2A each

Veti

@TLAS said in Replace fuse for broken fans:

Tornado-Like Fans - pulls ~2A each

thats not for a 3d printer, is it?

deckingman

@Veti said in Replace fuse for broken fans:

@TLAS said in Replace fuse for broken fans:

Tornado-Like Fans - pulls ~2A each

thats not for a 3d printer, is it?

Yes - 252 CFM - it's for blowing the parts off the build plate when the print finishes

Veti

@deckingman
i can see the headlines. tornado created by misconfigured 3d printer.

TLAS

@deckingman said in Replace fuse for broken fans:

@Veti said in Replace fuse for broken fans:

@TLAS said in Replace fuse for broken fans:

Tornado-Like Fans - pulls ~2A each

thats not for a 3d printer, is it?

Yes - 252 CFM - it's for blowing the parts off the build plate when the print finishes

lol. :). I guess I shouldn’t mention the 450 cfm one I have in there as well...