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Class t fuse without holder

Bluedog225

Texas
Joined
Nov 18, 2019
Messages
2,829
In one of the vids floating around, I saw a class t fuse, bolted to wire at each end, and the wire/bolt connection heat shrinked. That is, a fuse inline with no holder.

I thought it was brilliant. Is there any downside other than the trouble of replacing if blown?
 
I'd worry about the two wires putting some bending or twisting stress on the fuse. The holder keeps things stress free. Putting a Class T (or any) fuse between two pieces of big heavy stiff wire (for example, 2/0AWG or 4/0AWG) without any support is going to result in some unwanted stress on the fuse. That can't be good.
 
While I don't like hooking a fuse directly to wires hanging loose, I think putting a Class T fuse across a couple of appropriately spaced terminal blocks like these is perfectly fine, as long as nothing will touch the fuse (since there is no cover for it). Saves a few bucks off of buying a Class T fuse holder, especially since you have to get different fuse holders for different sized fuses all the time.
 
You could go one step further, and bolt the fuse between two bus bars. Bring all of the battery positives to one, and all of the loads to the other.
 
Use flexible bus bars on both sides and you can use zip ties to hold t fuse tight....and when you get enough spare change buy T fuse block and make less stressful sleep dreaming about T fuse braking free and running away from you or getting in touch with opposite battery side. Zapping is bad idea in everyone mind and very dangerous.
Good luck
 
Some specific fuses (Cable Limiters) are designed to be mounted this way... but they have a very different construction. (Cable Limiters are used when you have a bunch of parallel sets of wires sharing current and the main protection is insufficient for protecting the individual runs.)
 
" since you have to get different fuse holders for different sized fuses all the time."
No. I have not had that problem. There are only two physical size differences for the Class-T fuses I use. I just buy the holder for the fuse size I need. The holder does one important job, it keeps the two ends of the fuse 'locked' in alignment. It does this by having a common base to connect the fuse.
Please note; I always use a proper holder for whatever fuse I have. I advise to do that yourself.
 
I have argued the holder is an important part of the fuse,as a serious dead short that the t-class fuse is designed to extinguish can compromise the fiberglass body of the fuse, resulting in cable flying loose.
Other members posted instructions they interpreted to say I was incorrect, but I stand by my requirement for the fuse holder.
 
I have argued the holder is an important part of the fuse,as a serious dead short that the t-class fuse is designed to extinguish can compromise the fiberglass body of the fuse, resulting in cable flying loose.
Other members posted instructions they interpreted to say I was incorrect, but I stand by my requirement for the fuse holder.
It's amazing the risk people take to save a few dollars. What's cheaper? A fuse holder or burning down the house?
 
I have argued the holder is an important part of the fuse,as a serious dead short that the t-class fuse is designed to extinguish can compromise the fiberglass body of the fuse, resulting in cable flying loose.
Other members posted instructions they interpreted to say I was incorrect, but I stand by my requirement for the fuse holder.
In extreme conditions and in rush current at the max level this is possible to happen. This is why fuse holder is designed to keep fuse from separation. But we are here not to judge anyone everyone is responsible for his own safe way to design battery. Professional pack builders have a lot of experience and a lot of knowledge how to design safety by the code . So if someone runs on hot head who thinks that know all let him learn on his own mistakes.And other that are not afraid to ask questions and learn we should help them. No matter how it may sound stupid question if someone is not 100% sure ask questions there is no thing as being embarrassed.
 
Unfortunately electrical disasters caused by faulty workmanship can cause damage to other than the builder.
 
How about half a fuse holder? My pack has the last positive bus bar extended and the fuse attache to that. If the fuse breaks, the loose end attache to the cable to the inverter has no voltage.
 
How about half a fuse holder? My pack has the last positive bus bar extended and the fuse attache to that. If the fuse breaks, the loose end attache to the cable to the inverter has no voltage.
Unless it falls towards the battery…
 
Unless it falls towards the battery…
Yes, I took that into consideration extending the bus bar connection beyond the battery so it would not fall on the battery. Also my battery is covered in Lexan so the risk of anything falling on the battery is reduced. I agree that in most cases a fuse holder would be the best risk management strategy but my situation found a solution that eliminated an extra connection of a cable from battery to the fuse holder.
 
Finally high quality and performance power supply for my benchtop power
 

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Do any of you know where I can find a fuse holder for the Littlefuse Class T 400A JLLS fuse I finally found? I cannot find a fuse holder at all. Not sure why the company I got the fuse from (last one) did not sell them but I asked them to call before they ship hoping they have it and I just could not figure it out. Anyway, the specs are Amp rating=400, VAC (V)=600, VDC (V)=300 Thanks in advance.
 
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