What got me on this track was discovering the replacement fuse for the Trango ApexPlus/Lynx/Stratalink POE boxes is a 3.5 amp medium blow. It’s kind of amusing because the single radio power supply they sell is only rated 1.5 amps, so it can’t blow the fuse. But when I power it from a 6 amp Mean Well, the fuse glows like a little incandescent bulb for a fraction of a second before opening.
So I was just wondering if the medium blow fuses had their place. Some distributors like Allied don’t even have them in their catalog, so I guess they are a rare bird. I also learned from perusing the spec sheets that fast blow fuses actually take 30-60 minutes to blow until you get over 200% of rating, at 300% it comes down to milliseconds. That probably explains George’s experience with 1/2A fuses. But also with a 5A fuse on a Syncinjector, if the power supply can’t put out at least 240 watts, things are going to cook for awhile before that fuse blows. From: Forrest Christian (List Account) Sent: Wednesday, August 19, 2015 12:16 PM To: af Subject: Re: [AFMUG] medium blow fuses A fast blow fuse is really very very slow when compared to electronics. I'd recommend sticking with the fast blow fuses. If you're asking because you have nuisance blows I might consider just moving up a amp or so depending on what you're protecting. On Aug 19, 2015 6:47 AM, "Ken Hohhof" <af...@kwisp.com> wrote: I use fast blow 5x20 mm fuses for radios and other electronics, but recently became aware that medium blow fuses exist. Not widely available, but examples are Belfuse 530-5MT and Littelfuse 233 series. So is anyone using these? Any advantage? I'm thinking devices that might have enough inrush current to blow a fast blow fuse, although that hasn't been a problem so far.
