[Milsurplus] Fuses to protect transformers

[hwhall at compuserve.com]

>
You might try placing some amount of inductance (RF choke?) in the
transformer secondaries.? I can't help you with an inductance value, but
it's worht considering and researching.
>

Thanks for the thought, it's novel & sometimes that leads to breakthrough methods, but I expect that an inductance large enough to save a secondary rated for just a couple hundred milliamps from a short circuit would, for 60 Hz, be larger than there is room in or on the chassis to install. It would be interesting to experiment with, but wouldn't such a choke also impede the normal current flow? Might require careful design & contruction. An RF choke would be next to invisible in its effect, I think. I really do believe that what is needed in the short run is something to disconnect the winding as fast as possible.

So far my findings seem to be that HV rated fuses exist (450, 500 & 1000 VAC) but often are not available in smaller current sizes, such as less than one or three amps. I'm not done looking, but have had to pause for another project. I am heartened by several folks who indicate the 250VAC fuses have been found to serve adequately. I may run a few through a short test to see if they part clean or flash a lot of vapor to the interior surfaces. Ought to be fun!

Wayne
WB4OGM