Topics

Fuse size for UBITX

Jason N3YUG
 

I am starting to build my uBITX here, and am wondering what size fuse I should use?  


Jason
N3YUG

John McFadden
 

A prior discussion said a fast blow 2.0 amp, I've only seen draws in the 1.3 amp range,  so I've been happy with that fuse so far. 

John

On Jan 6, 2018 11:47 AM, "Jason N3YUG" <jbr13@...> wrote:
I am starting to build my uBITX here, and am wondering what size fuse I should use?  


Jason
N3YUG

Jerry Gaffke
 

I think the ideal is a 1n400x diode for reverse battery protection plus a 0.5 Amp fuse, both in series from the 12v supply into the main uBitx board.
Then a separate 3 Amp fuse for power into the IRF510 finals, no diode as we don't want to lose power due to the forward voltage drop here.

Could reduce those fuses to 0.25 Amps and 2 Amps respectively for better protection, but might be more likely to blow unnecessarily.

Jerry


On Sat, Jan 6, 2018 at 01:14 pm, John McFadden wrote:
A prior discussion said a fast blow 2.0 amp, I've only seen draws in the 1.3 amp range,  so I've been happy with that fuse so far. 
 

Don, ND6T
 

I've been using a polyfuse in series with the entire power, followed by a 1N7001 to ground for 3 weeks now. Although only rated at 1.5 amps, no problems.
ND6T