Does the AWG size of the fuse holder wire matter?

[poot_traveller]

[font=Tahoma,Verdana,Arial,Sans-Serif]I have 30 Amp fuses and fuse holders with [/font][font=Tahoma,Verdana,Arial,Sans-Serif][font=Tahoma,Verdana,Arial,Sans-Serif]14 AWG[/font] size wire.  The rest of my wiring is 10 gauge.[/font]

[font=Tahoma,Verdana,Arial,Sans-Serif]Does the wire size matter on the fuse holders (for blade fuses) or should I get fuse holders with 12 AWG wire?[/font]

 

[highdesertranger]

yes size matters. I can't believe I said that.

they make inline fuse holders with 10gauge wire. like this one,

https://powerwerx.com/atc-ato-inline-fuse-holder-10-gauge-red

highdesertranger

 

[Elbear1]

It matters but wire size and LENGTH = voltage drop. So if its as short as possible it will have less impact.

 

[B and C]

Do not connect different size wires together unless you change the fuse to match the capacity of the smaller gauge wire. A smaller wire also adds resistance (voltage drop).

 

[poot_traveller]

yes size matters. I can't believe I said that.

they make inline fuse holders with 10gauge wire. like this one,

https://powerwerx.com/atc-ato-inline-fuse-holder-10-gauge-red

highdesertranger

OK, now I've got something to work with. I'm looking for fuse holders with 10 gauge wires.

Thanks

 

[poot_traveller]

It matters but wire size and LENGTH = voltage drop. So if its as short as possible it will have less impact.

The solar feed will be about one metre, and the controller to battery will also be about one metre. The battery to inverter will be less than two feet.

Total length: Just over 2.5 metres

EDIT: Actually about 3 metres.

 

[poot_traveller]

Do not connect different size wires together unless you change the fuse to match the capacity of the smaller gauge wire. A smaller wire also adds resistance (voltage drop).

I'm currently in the market for fuse holders with 10 gauge wire. Pretty easy finding such an item in the US, but here in NZ it's going to be quite a challenging task. Visited three electrical shops today and two out of three didn't have fuse holders of any kind. The third only had fuse holders with 14 AWG size wire and the auto electrician that sold me the fuse holders said the wires are fine, don't need bigger wires. He didn't even know or ask what I was planning on using these for.

 

[regis101]

Stay away from that shop

 

[Elbear1]

Even 10awg is undersized fyi. Many MC4 come in that gauge and thats ok, not ideal but ok. But the run from the controller to the battery should be at least 6awg. You can run 2 or 3 10awg wires and effectively give yourself a bigger gauge.

IDK if you can get these in NZ but they handle 4awg and probably 2awg.

https://www.amazon.com/ANJOSHI-Prot...inline+fuse&qid=1568299668&sr=8-16&th=1&psc=1

I use the kind of fuse holders youre talking about with different size wire (10awg) but for low current usb/12v plug. Its not the end of the world but should NOT be used inline with panels or from co troller to battery. Just too small.

 

[Ticklebellly]

Take a close look at the cross section of the fuse material itself. Cut the leads on the fuse holder as short as practical and stop worrying. It is the total length of thinner wire in the cable run that needs to be minimised.

Another way to minimise the length of small cross sectional wire in a cable run is to use cartridge fuse holders rather than blade fuse style holders. Cartridge fuse holders often have solderable connection tabs so you can have serious size copper all the way up to the clips tha hold the fuse. A lot of cartridge type fuse holders used in sound equipment have screw down connections so again, you can minimise the total length of narrow copper or conductor in the total cable run by having serious size copper all the way up to the fuse material itself.

 

[highdesertranger]

please don't use car audio stuff especially the stuff that has set screws to pinch the wire like the one linked to above. 99% of it is junk. also most DC circuit breakers only work in one direction. the power can flow both ways but there is only circuit protection one way. highdesertranger

 

[Giuseppe Hardblast]

You'll burn up those thin wires before the fuse

 

[Ticklebellly]

99% of it is junk. 

I must have lucked out getting the 1% that is very very good.

I use MIL-Spec fuses and use fuse holders with gold plated clips.   I get a smaller voltage drop across a fuse when compared to a Cct Breaker in the same position.   I have never had a fuse blow in my installations.   I also do a Failure Mode Analysis on the system before deciding where and how many fuses to install.    Both the DC to DC chargers I currently use are internally fused so they take care of themselves.

If you do not have access to the precision measuring equipment necessary to measure voltage drops across fuses and fuse holders and mechanical connections, you can use a cheap Infra Red thermometer to find heat nodes and HR joints.    Organise for a current just lower than the fuse rating in that circuit to flow for about 15 minutes before running the thermometer along the wire run.   HR joins stand out like Xmas lights.

If you are so worried that the leads to a fuse holder will negatively effect transmission losses in that wire run, it would be worthwhile checking what the voltage losses are across the wire run, end to end.

 

[poot_traveller]

Even 10awg is undersized fyi. Many MC4 come in that gauge and thats ok, not ideal but ok. But the run from the controller to the battery should be at least 6awg. You can run 2 or 3 10awg wires and effectively give yourself a bigger gauge.

IDK if you can get these in NZ but they handle 4awg and probably 2awg.

https://www.amazon.com/ANJOSHI-Prot...inline+fuse&qid=1568299668&sr=8-16&th=1&psc=1

I use the kind of fuse holders youre talking about with different size wire (10awg) but for low current usb/12v plug. Its not the end of the world but should NOT be used inline with panels or from co troller to battery. Just too small.

6 AWG is easier to find than 10 AWG. If I can't find 10 AWG, I'll settle for 6 AWG.

All my other wires are 10 AWG, so I prefer to keep the fuse holder wires at 10 AWG.

 

[poot_traveller]

Take a close look at the cross section of the fuse material itself. Cut the leads on the fuse holder as short as practical and stop worrying. It is the total length of thinner wire in the cable run that needs to be minimised.

I'm going to use blade fuses because it's easier than cartridge fuses.

So much different advice, all of the advice seems logical but strangely opposing to each other.

Your advice is no different, very logical advice but opposing to the advice of others who insist on a larger wire size. Which should I go with? lol

My choice of advice doesn't count either because I seem to choose the answer I WANT to hear. And that may not necessarily be the correct answer.

The most popular opinion seems to be fuse holders with 10 AWG wire, so I'm going with that. But I'll combine it with your advice to shorten the wires as much as possible.

Thanks

 

[poot_traveller]

please don't use car audio stuff especially the stuff that has set screws to pinch the wire like the one linked to above. 99% of it is junk. also most DC circuit breakers only work in one direction. the power can flow both ways but there is only circuit protection one way. highdesertranger

Keep in mind the car audio stuff here in NZ is mostly NZ made stuff, not American made junk

But you seem pretty insistent on it, so I'll try to avoid car audio stuff if I can, it's just that my choice of options here is limited and I might have no other choice but to choose car audio stuff.

There is a boat shop down the road that sells marine stuff, I'll take a look there for fuse holders, I might get lucky.

 

[poot_traveller]

You'll burn up those thin wires before the fuse

Duly noted.

 

[Elbear1]

6 AWG is easier to find than 10 AWG.  If I can't find 10 AWG, I'll settle for 6 AWG.

All my other wires are 10 AWG, so I prefer to keep the fuse holder wires at 10 AWG.

Just so we are clear you know the higher the number the smaller the wire? Maybe its different over there. 10 gauge wire (2.58 mm) is like pretty small stuff. Its like speaker wire. Battery cables are 2 gauge (6.54 mm)....size of a finger

10 gauge x 1 meter wire on say a 20 amp system is bordering on, if not outright, dangerous.

 

[Elbear1]

Keep in mind the car audio stuff here in NZ is mostly NZ made stuff, not American made junk

But you seem pretty insistent on it, so I'll try to avoid car audio stuff if I can, it's just that my choice of options here is limited and I might have no other choice but to choose car audio stuff. 

There is a boat shop down the road that sells marine stuff, I'll take a look there for fuse holders, I might get lucky.

What I linked you is what I use. Wouldnt do so if it wasnt good as I would be changing it out on my system. It is not a one way kill. It is a physical disconnect with zero continuity when tripped. Then it can be reset like a circuit breaker.

 

[highdesertranger]

you know there is always Maxi Fuse holders. these have terminals so you eliminate the small wire issue. they will handle 4-14 AWG.

https://www.bluesea.com/products/5006100/MAXI_Fuse_Block

the fuses are very common and regular auto part stores carry them. at least around here.

also here in the states car audio junk is mad in China.

highdesertranger