What's a quality fuse and holder to use inline with the battery connection? Mine is getting HOT at half the rated amperage!

[Gentleman Mike]

I got this 150 amp fuse to go inline on my 1/0 AWG battery cable: https://www.amazon.com/dp/B0BW4TLBST

And even just charging my 48 volt batteries at 80 amps, this fuse and holder get really hot after 15 minutes! Like I can't keep my fingers on it for more than 10 seconds. I turned my charge current down to 40 amps until I can fix this issue, and even at 40 it gets warm. Not warm enough to scare me, but there is clearly a problem here that needs to be resolved.

How can I fix this, or am I just using an inappropriate product here? What brand and type do the experts here recommend I use?

 

[hwy17]

Blue sea is good.

 

[ricardocello]

“ Features a Solid Zinc Core for Maximum Current Flow”

Zinc is less than 1/3 the conductivity of copper. It will dissipate 3x the heat.
Look for nickel or tin plated copper. Or even Aluminum.

<<Link Deleted>>
I just noticed you were 48V, and those Blue Sea were only good to 32VDC.

 

[Sennen]

While Skar Audio makes decent equipment, they make it for 12v systems. Likely rating all of their stuff for 20v max. This matters. Agree on blue sea. Check voltages of whatever you buy. If it's not listed, guess from context. Car Audio mfg only care about normal range for their intended application (10-15v)

 

[Gentleman Mike]

Thanks all, I'll look into Blue Sea.

Do you think it would be a good idea to just not use a fuse at all for a few days until I can get a replacement? Seems to me like it's the better option vs the fuse getting stupidly hot under heavy load.

 

[Sennen]

Thanks all, I'll look into Blue Sea.

Do you think it would be a good idea to just not use a fuse at all for a few days until I can get a replacement? Seems to me like it's the better option vs the fuse getting stupidly hot under heavy load.

Never a good idea to go without a fuse. Is the casing deforming from the heat? (Example of deforming by the electricians who built my house without a torque wrench)

 

[ricardocello]

I recommend you keep the charging current down until you get a new fuse / holder.

I suspect the ANL fuse you have isn’t rated for 48/57VDC either.
Why does it matter? Because even if the fuse blows, the DC may continue to arc right across it at the higher voltages.

 

[Gentleman Mike]

Never a good idea to go without a fuse. Is the casing deforming from the heat? (Example of deforming by the electricians who built my house without a torque wrench)
View attachment 199885

That's a scary pic.

It hasn't deformed, so far. I'll just leave it in place and keep the charge current down while making sure to not draw too heavy of a load while running off batteries until I get a replacement..

 

[ricardocello]

I also recommend you search this forum for:
Class T, MRBF, MEGA, ANL, fuses and holders

These guys/gals have argued about this stuff for a long time, there is lots of shared experience.

 

[Sennen]

https://www.amazon.com/dp/B0753HYKVQ

Ignition protected means it won't catch on fire. If you want a cheap example of this property, take a blowtorch to a Wago 221.

 

[scottpeter]

For your load, the only option is a Class T. ANL type is totally inappropriate.

Check MarineHowTo.com for an explanation of fuse types.

 

[rodrick]

48 volt systems need to use class t fuses it’s probably going to run $75 to $100 for fuse and holder

 

[JWLV]

This is what I use with my 30KWH rack batteries. Using my thermal imager camera, even under heavy loads, the temperature of the fuse is nearly the same as the ambient temperature around it.

I paid $36.99 in Nov 2023. It's now $29.99.

https://www.amazon.com/gp/product/B0C6JKFPKR

 

[scottpeter]

While that is technically a Class T, the fuse is a crap Chinese clone. Real risk of fire.

A proper class T fuse of that rating is at least $60 Go with quality, like Bussman. That is who BlueSeas use.

 

[Nobodybusiness]

Never a good idea to go without a fuse. Is the casing deforming from the heat? (Example of deforming by the electricians who built my house without a torque wrench)
View attachment 199885

How did your neutral bar get burnt?

 

[Sennen]

How did your neutral bar get burnt?

2 of those were not torqued at all. The rest were tightened by the incredible hulk himself. Noticed that when i swapped a breaker to af/gf combo. House is 20 years old.

 

[Gentleman Mike]

Thanks all, I went with a Blue Seas holder and class T fuse. It should be here in a few days.

 

[Supervstech]

I got this 150 amp fuse to go inline on my 1/0 AWG battery cable: https://www.amazon.com/dp/B0BW4TLBST

And even just charging my 48 volt batteries at 80 amps, this fuse and holder get really hot after 15 minutes! Like I can't keep my fingers on it for more than 10 seconds. I turned my charge current down to 40 amps until I can fix this issue, and even at 40 it gets warm. Not warm enough to scare me, but there is clearly a problem here that needs to be resolved.

How can I fix this, or am I just using an inappropriate product here? What brand and type do the experts here recommend I use?

Do you have a picture of the fuse installed?

 

[seneysolar]

For your load, the only option is a Class T. ANL type is totally inappropriate.

Check MarineHowTo.com for an explanation of fuse types.

What makes it inappropriate? Most inverter companies, even Victron carry their own line of ANL fuses / holders and specify their use in the installation manual.

48 volt systems need to use class t fuses it’s probably going to run $75 to $100 for fuse and holder

ANL fuses are rated to 80V. Nothing wrong with using one in a 48V system.

I think the major issue is all of the cheap junk out there on Amazon. If the ANL fuse is in a plastic body, personally id stay away from it. Bussmann rivets theirs together with phenolic plates and are much better quality.

Class T are great, but not "required" in most cases.

 

[Supervstech]

For basic load protection, anl is fine, it will pop under standard overloaded draw and protect the wire.
The issue comes in when a catoustrophic failure occurs and massive short circuit causes full cell output in a bank.
At 48v, 15000A are possible, and anl would simply pass the arc along, and fail to break the circuit.
ClassT can extinguish the arc.