Thread: Fuses
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Old 22nd Mar 2014, 12:49 pm   #44
Tubeglow
Retired Dormant Member
 
Join Date: Mar 2014
Location: Wolverhampton, West Midlands, UK.
Posts: 153
Default Re: Fuses

Quote:
Originally Posted by kalee20 View Post
I do confess to using a 250V-rated fuse (1.25" type) on a 400V 10A DC rail, but it was to hopefully save the PCB in case of a downstream fault, not as a primary means of safety protection. As it happened, it was never put to the test.
What type of circuit was it?

Its always been a bit difficult to protect HT+ in valve amps. You can use microwave fuses but they are a bit big.
I know in the past any fuse is better than no fuse..I do cap quench on B+.
The HT windings are often mA rated, so its quick blow. Then you have the cap charge to deal with at power up.
Some people put fuses in the cathode of OP valves because its low voltage.
But if you get a supply cap short or OP Tx fault its another story.

Tubeglow.

Last edited by Tubeglow; 22nd Mar 2014 at 12:57 pm.
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