Fuse Query?

[Adrian]

The fuse in one of my Paramounts blew on startup after being idle for a while .  It worked great before this.
I didn't have any of the supplied fuses on hand (came with F1AL 250V - a 1A GMA type) so I went to Radio Shack and got a bag of 4 1A GMA Type fuses (the Radio Shack Brand).
I kept blowing these fuses on start.  The unit worked fine with the fuse block from the other channel (original supplied fuse) but these new fuses just wouldn't cut it.
Fuse specs and quality vary alot, maybe I got a bad lot (damn you, Radio Shack!).

Should I try a 1.5A GMA, a 1A GMC (time delay or slow), or short it out (just kiddin')?

[galyons]

Fuses blow for a variety of reasons.  Some are benign.  You need to determine if you have an issue that needs to be addressed. Run the resistance and voltage checks. Make sure both of the tubes are still good. You want to know why the fuse blew.  F1AL is the designation for a fast blow 1 amp fuse.   Be careful going to a higher amperage fuse, you may make another component the "new" fuse.  You do not want to do that!

Cheers,
Geary

[Adrian]

Thanks Geary
The unit works great with the original type fuse from the other channel.  Its just blowing the Radio Shack fuses.

[galyons]

Thanks Geary
The unit works great with the original type fuse from the other channel.  Its just blowing the Radio Shack fuses.

Perfect! Should make it easy to do the tests!     Remember the other "original" blew before, hence why you are trying the RatShack fuses.  Better safe than sorry!

Cheers,
Geary

[Paul Joppa]

Fuses from different makers often use different materials for the same specification, so while they may meet the spec the surge capacity may be different. Slow blow usually works best with audio gear which has conventional capacitor-input power supplies; they are more expensive and hence hard to find.

[Adrian]

Thanks Paul
All of the fuses supplied in BH kits are fast-acting.
This could be for proper protection or simply because they are easier to find and less expensive.
I default to the original design unless BH has designed in enough margin to allow for a time-delay fuse.

In general, does BH design allow for time-delay fuse protection?

I will try another source for the replacement fuse.
Like I said - probably just a manufactered variance or from a bad lot.

Geary
The unit runs great with a BH supplied fuse - all resistances and voltages are proper.
The original fuse may have been at the wrong end of the specs and ended up with a shorter life.

_________________
It seems that everyone likes to trash Radio Shack, but I have had good luck with almost everything I have gotten from them.  They definately are not a high-end dealer and in some respects I would admit that on occasion you might just get what you paid for.

[Paul Birkeland]

Put a 2A fuse in it and see what happens. 

-PB

[Adrian]

Seriously, PB!
It works great with a F1AL 250V fuse from another BH kit.  The Radio Shack fuses were the problem.
Why would I want to lower the protection offered by a 1A fuse by installing a 2A fuse?


I installed a 1 Amp slow-blow from the same Radio Shack (works great) and ordered some 1A GMA fuses from Cooper Bussman so I can then put in the same rated fuse supplied by BH.

[Paul Birkeland]

Yeah, that has been my experience with RS fuses; you just have to go a little bigger for them to work.

[Adrian]

PB
Thanks for the info.