1/0 gauge wire suggestion?

[wew lad 5,000+ posts]

good luck finding a 350 amp fuse, or anything over 300 amps that works properly for that matter... I've been wondering myself how I'd ever get a fuse that large if I just use 2 runs of 2/0 with dist blocks instead of a ton of 4 gauge and 0 gauge runs. I've read you can stack similar fuses and it doubles the amperage rating but I'm not sure if that's the ideal way.

 

[JarodM]

good luck finding a 350 amp fuse, or anything over 300 amps that works properly for that matter... I've been wondering myself how I'd ever get a fuse that large if I just use 2 runs of 2/0 with dist blocks instead of a ton of 4 gauge and 0 gauge runs. I've read you can stack similar fuses and it doubles the amperage rating but I'm not sure if that's the ideal way.

Stacking fuses is definitely not a good way to go. Yes it may theoretically allow more amperage through, but electricity goes where it wants and without dedicated runs for each fuse, it could still try and push more than one of the fuses could handle since maybe it has a fraction less resistance than the other fuse and you'd just end up blowing all the fuses.

What's wrong with this fuse?

350A Fuse - XS Power

 

[wew lad 5,000+ posts]

from what I've seen the larger you go with a fuse, the amount of power it can handle in bursts goes up exponentially. I found a 500amp anl fuse and after doing some research and looking at the specs it takes 5000amps for it to be interrupted. That's more amperage than a battery can put out and the fuse wouldn't blow fast enough to save anything anyway.

 

[adulbrich 5,000+ posts]

good luck finding a 350 amp fuse, or anything over 300 amps that works properly for that matter... I've been wondering myself how I'd ever get a fuse that large if I just use 2 runs of 2/0 with dist blocks instead of a ton of 4 gauge and 0 gauge runs. I've read you can stack similar fuses and it doubles the amperage rating but I'm not sure if that's the ideal way.

Stacking fuses is definitely not a good way to go. Yes it may theoretically allow more amperage through, but electricity goes where it wants and without dedicated runs for each fuse, it could still try and push more than one of the fuses could handle since maybe it has a fraction less resistance than the other fuse and you'd just end up blowing all the fuses.
What's wrong with this fuse?

350A Fuse - XS Power

I have two 300 amp fuses for each 2/0 gauge wire. Stacking fuses is perfectly fine. No, there is nothing wrong with that 350 amp XS fuse either.

 

[JarodM]

from what I've seen the larger you go with a fuse, the amount of power it can handle in bursts goes up exponentially. I found a 500amp anl fuse and after doing some research and looking at the specs it takes 5000amps for it to be interrupted. That's more amperage than a battery can put out and the fuse wouldn't blow fast enough to save anything anyway.

I think you are getting terms confused. It doesnt take 5000A to blow the fuse, the fuse is capable of interrupting 5000A. Meaning, when it blows at its rated amperage (actually it usually takes 125-150% of the rating to blow the fuse, depending on the fuse and its make) it can hold back up to 5000A, so it creates a gap large enough so that 5000A cant arc across to gap and ruin your components. This applies more to home electrical systems where they could see a huge spike from a blown transformer, lightning, etc. You're not going to see that kind of amperage in your car and a fuse rated at 500A will blow at its specd rate which could be anywhere from 500 to 750A

 

[JarodM]

I have two 300 amp fuses for each 2/0 gauge wire. Stacking fuses is perfectly fine. No, there is nothing wrong with that 350 amp XS fuse either.

So, because you do it, it makes it "perfectly fine"? Hmm, yeah, no.

 

[adulbrich 5,000+ posts]

So, because you do it, it makes it "perfectly fine"? Hmm, yeah, no.

Hmm, yeah, yes. It is fine. //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[wew lad 5,000+ posts]

I think you are getting terms confused. It doesnt take 5000A to blow the fuse, the fuse is capable of interrupting 5000A. Meaning, when it blows at its rated amperage (actually it usually takes 125-150% of the rating to blow the fuse, depending on the fuse and its make) it can hold back up to 5000A, so it creates a gap large enough so that 5000A cant arc across to gap and ruin your components. This applies more to home electrical systems where they could see a huge spike from a blown transformer, lightning, etc. You're not going to see that kind of amperage in your car and a fuse rated at 500A will blow at its specd rate which could be anywhere from 500 to 750A

the problem i have is that it takes more than one second for the fuse to open at 500 to 750 amps. I might be incorrect, if larger fuses are effective I'd like to use them. To be honest I'm not too familiar with the subject but this is what I've gathered from others opinion.

theres a chart showing the relationship between percentage of rated current and time for a 500amp fuse shown here: https://www.bluesea.com/products/5137/ANL_Fuse_-_500_Amp

 

[JarodM]

the problem i have is that it takes more than one second for the fuse to open at 500 to 750 amps. I might be incorrect, if larger fuses are effective I'd like to use them. To be honest I'm not too familiar with the subject but this is what I've gathered from others opinion.
theres a chart showing the relationship between percentage of rated current and time for a 500amp fuse shown here: https://www.bluesea.com/products/5137/ANL_Fuse_-_500_Amp

You're correct in that the length of time before it blows can be longer depending on the % of the rated current its seeing at the time of failure, but the chart is also a general chart for 50 to 750A fuses, so a larger fuse wont take any longer to trip than a smaller fuse if they are both seeing say 400% of their rating at time of failure.

 

[adulbrich 5,000+ posts]

Fuses take a while to blow, even above their rated current.

There are "quick blow" fuses, if that's what you want.

I mainly use fuses to protect against electrical failure due to a short. Not really worried if thay don't blow immediately, as long as they prevent a fire.

@JarodM;

With your logic, multiple runs are useless, yeah? "Electricity goes where it wants". So one run of 1/0 is as good as 10 runs of 1/0??? Same thing applies to fuses buddy.

Car audio wire is made up of many small strands. Woth your logic, electricity would flow through each strand individually and melt everything. Honestly, give me a break

 

[JarodM]

[quote name='adulbrich']Fuses take a while to blow, even above their rated current.

There are "quick blow" fuses, if that's what you want.

I mainly use fuses to protect against electrical failure due to a short. Not really worried if thay don't blow immediately, as long as they prevent a fire.

@JarodM;

With your logic, multiple runs are useless, yeah? "Electricity goes where it wants". So one run of 1/0 is as good as 10 runs of 1/0??? Same thing applies to fuses buddy.

Car audio wire is made up of many small strands. Woth your logic, electricity would flow through each strand individually and melt everything. Honestly, give me a break[/QUOTE]

Ha! Ok, obviously you dont understand. Get back to me when you've got a clue.

 

[adulbrich 5,000+ posts]

Ha! Ok, obviously you dont understand. Get back to me when you've got a clue.

It's you who does not understand.

 

[wew lad 5,000+ posts]

Do both fuses have exactly the same resistance? You need to have a background in understanding the laws of physics when it comes to electricity before you can understand why having two fuses would cause problems. Two fuses stacked will blow sooner than a single fuse that is equal to the rating of the two stacked fuses. Try it. Do you think the fuse that's stacked on the top has the same resistance as the one closer to the source?

Is the difference negligible for what we're doing? Maybe. Only a thorough test could say, and I don't have the resources to do that. However, theory does tell us that there is a difference between two stacked fuses and a single fuse.

 

[adulbrich 5,000+ posts]

Do both fuses have exactly the same resistance? You need to have a background in understanding the laws of physics when it comes to electricity before you can understand why having two fuses would cause problems. Two fuses stacked will blow sooner than a single fuse that is equal to the rating of the two stacked fuses. Try it. Do you think the fuse that's stacked on the top has the same resistance as the one closer to the source?
Is the difference negligible for what we're doing? Maybe. Only a thorough test could say, and I don't have the resources to do that. However, theory does tell us that there is a difference between two stacked fuses and a single fuse.

I have two runs of 1/0 that are each fused with 300 amp fuses. They converge and connect to 2/0, which goes into my amp inputs. That is fine. A single 300 amp fuse would not be the best option.

Total, I have 1,200 amps of fusing for my amplifier input wires. At 1 ohm nominal, I charge at 14.8 and the lowest I drop to is 14.4 at idle. After I get another alternator, I'll be running the M4a at .25 daily. If I maintain a high voltage, this will not be an issue.

 

[n2audio 5,000+ posts]

Jarod, Mitchell...

Your hypotheses are totally unfounded in anything relating to fact.

Using a pair of fuses in parallel would be no better or worse than using one.

Look at fused d-blocks for example. If you're using two different sized fuses does the lower current side get choked for power? No.

So one fuse has maybe 1% more resistance. So? It would blow at 1% less current. It's not like it would for some unknown reason just resist all current flow leaving the other fuse to try to pass it all.

You don't need to understand ANY physics theory to understand this. Just use some common sense.

Totally baseless.

Move on.