Finding replacement fuse caps!

[nevetslab]

This is an on-going task maintaining a large fleet of rental backline gear. Just last week I had to replace a Littelfuse '345' fuse holder in a Peavey Classic 50 Combo amp, and the week before, a different Littelfuse '345' fuse holder in a older Fender Twin Reverb. The current Fender Twin's, Deluxe Reverbs and others are using the 'current' Littelfuse 345 Series fuse holders (P/N 0345LF8H), whose fuse cap does NOT fit these older Littelfuse '345' fuse holders, as the mechanical design is quite different in the throat and flange details. And, I can't find any data sheet that mates up with this older design on their website. Here's images of the current 345 Series holder & 3AG type mating cap (also uses a 5 x 20mm cap).



The first two images are P/N 03453LF8H....shock-safe 3AG Fuse Holder & Cap. The next two are also type 345's, and in getting the data sheets ready to add to this post, I think I found the missing information on one of the type 345 data sheets in my files. I haven't yet tried to purchase any of the fuse caps for those, until now, and hopefully this exercise will lead to being able to get replacements.

Littelfuse_Fuse_Holder_345_Panel_Mount_Datasheet.p-1317217.pdf

Datasheet for the first two images

Littelfuse 345 Series Holder.pdf

On page 3 of the second datasheet, it lists the mating fuse cap (knob only, as they call it) for each '345' holder style. So, my mystery unfolds. Now to see if I can still purchase those parts. It gets old not having a supply of all the different types of fuse caps in use on all of the gear in our inventory, and, while it does make me more money having to pull a chassis from a cabinet and replace an entire fuse holder for lack of that silly part, it still is a PITA.

First attempt to find a fuse cap for one of the 'older' 345 style holders on Mouser is unsuccessful.

[Leo_Gnardo]

Now to see if I can still purchase those parts. It gets old not having a supply of all the different types of fuse caps in use on all of the gear in our inventory, and, while it does make me more money having to pull a chassis from a cabinet and replace an entire fuse holder for lack of that silly part, it still is a PITA.

CE/Antique carries a couple of fuse caps. Other than that, I dunno where to look. Over the course of decades I've developed a coffee can full of spare odd fuse caps plus other related bits 'n bobs. It comes in handy once or twice a year.

[Justin Thomas]

Yah, anything that is cheap in a junk shop that I can strip I do, just for times like these... Other than replace the whole thing, I don't know besides part out another amp....

Justin

Justin

[nevetslab]

I found Digi-Key had a page for the Littelfuse 345 603-020, but zero stock, 100 pcs min qty. Part looked like what I was seeking for the knurled knob version. Allied was a waste of time, and Newark denied me access to their website altogether (XP O/S, Firefox browser). I've already exhausted my boneyard of fuse caps.

I did find the screw-in cap for the older 345 series that has the notched front, which came out of the Peavey on ebay. Then, found new complete cap-style versions of that older 345 also on ebay, but saved that auction, having found a better deal on the current 345 series in qty.

[g1]

$10 minimum.
https://www.fusesunlimited.com/circu.../03450603hx020


edit: fusesunlimited.com seems to be a good bet for any obscure fuse/circuit protection type needs.

[nevetslab]

$10 minimum.
https://www.fusesunlimited.com/circu.../03450603hx020


edit: fusesunlimited.com seems to be a good bet for any obscure fuse/circuit protection type needs.

Ah, excellent. I was on their site earlier today, kept clicking on their Fuseholder Folder, but it would only open to Fuses, and not FuseHolders, and I finally gave up on them. Firefox browser issue again, I wonder? Thanks, g1!

[g1]

I was on their site earlier today, kept clicking on their Fuseholder Folder, but it would only open to Fuses, and not FuseHolders, and I finally gave up on them.

Yikes! I just tried it and had the same problem if I clicked on 'products'. (I had found the part via google search)
If you scroll down the main page, and click on 'sitemap', the website will become more usable:

https://www.fusesunlimited.com/sitemap.aspx

[nevetslab]

Yikes! I just tried it and had the same problem if I clicked on 'products'. (I had found the part via google search)
If you scroll down the main page, and click on 'sitemap', the website will become more usable:

https://www.fusesunlimited.com/sitemap.aspx

I used your 'back door' path, and went on today, set up an account and ordered the fuse caps. So, two more found, more to go (Bussman, and who-knows-what-else).

[nevetslab]

An update on the fuse caps. Having bought a small stash of the Littelfuse P/N 03450603HX020 that g1 had found, which led to Fuses Unlmited, the Fender Twin Reverb I have on the bench right now, having date codes from 2005 and 2006 inside on the bias pot & S/B switch, this generation has the 'older' Littelfuse 345 Fuse holder that uses that P/N above. Images are here:



That fuse cap assy isn't stocked at Mouser, but is the part that you'll find on the late 90's thru probably the next 10 yrs from Fender, before they changed to the current 345 series like these:



Those parts you CAN find inventoried at most distributors of Littelfuse. Of course the fuse caps of the newer series do NOT work on the older series, and vice-versa.