KnuKonceptz claimed ampacity

[ejschultz 10+ year member]

You've stated your obviously limited knowledge. Turn on a light and see how it really works. The internet should educate people. I've not the time to find a link for you.

That 20000 foot run of 1/0 at 265 amps will probably be brighter than a 60 watt bulb.

 

[ejschultz 10+ year member]

Considering you'll have a voltage drop of 531v, I don't think you'll make it.

According to the OP it will work, and somehow I'm the one who has shown my "obviously limited knowledge."

 

[MakeshiftAudio 10+ year member]

That 20000 foot run of 1/0 at 265 amps will probably be brighter than a 60 watt bulb.

I want to go through the math on this again, but I'm too tired.

20*0.09827=1.9654 ohms

(265*265)*1.9654=138020.215W

Oh **** yes that'll glow.

 

[smoka 10+ year member]

In other words, 0.157226584 degrees C/second, or 0.2830079 degrees F/second. Five seconds, and it's slightly more than a degree hotter. :\ I don't know if I would run it for too long. Let's run this for five minutes, assuming that none of the energy is lost/absorbed by the environment. 0.2830079(60*5)=84.90237 degrees F. I am not about to go into the math for dissipation of this heat into the surrounding air/insulation. After consideration, I would say the wire has a temperature rise of about 50-60 degrees F after five minutes.

But as the wire heats up, the resistance changes right? (or did your equations account for that because I didn't really read your whole post).

Also what type of eng are you? I'm (EE) industrial controls.

 

[McIntosh 10+ year member]

I would recommend people to go back to page 4 and read post #60. :\ Then comment on that.

Read that and commented as I recall. Heat generation, insulation breakdown. I squared R basically. Does that change the fact the length of the conductor has absolutely no effect? People here seem to think a short wire can carry more current than a longer wire (of the same size). This myth needs to be debunked.

 

[MakeshiftAudio 10+ year member]

But as the wire heats up, the resistance changes right? (or did your equations account for that because I didn't really read your whole post).
Also what type of eng are you? I'm (EE) industrial controls.

It changes roughly, but not enough to change the numbers to matter.

I'm not an engineer yet. I don't know the fields, but I'm on my way to being one. Some sort of electrical engineer. Thinking about RF of analog/digital circuit fields.

 

[ejschultz 10+ year member]

Read that and commented as I recall. Heat generation, insulation breakdown. I squared R basically. Does that change the fact the length of the conductor has absolutely no effect? People here seem to think a short wire can carry more current than a longer wire (of the same size). This myth needs to be debunked.

Go ahead and debunk it with your 20000 feet of 1/0 and 265 amps. You'll see at that point that the length does matter.

 

[ejschultz 10+ year member]

It changes roughly, but not enough to change the numbers to matter.
I'm not an engineer yet. I don't know the fields, but I'm on my way to being one. Some sort of electrical engineer. Thinking about RF of analog/digital circuit fields.

Not that it matters too much, but I'm also currently seeking a degree in electrical engineering. I'm in the Electrical and Computer Engineering Tech. program at Purdue. Two years down and two to go.

 

[MakeshiftAudio 10+ year member]

Read that and commented as I recall. Heat generation, insulation breakdown. I squared R basically. Does that change the fact the length of the conductor has absolutely no effect? People here seem to think a short wire can carry more current than a longer wire (of the same size). This myth needs to be debunked.

:facepalm: It's kind of hard to grip.

A short wire can carry a LARGE amount of current, but as long as it doesn't heat enough to cause a thermal runaway issue. This short wire can be using for a short period of time with a high current.

For example, I have made a pulse discharge system capable of 100kA pulses, but I only use 300kcmil in a 1' run for the interconnects. There is not enough heat generated in this 100kA 1mS(I think) pulse to break the connection or to get worried about extraneous heating.

I've had an argument with TnT_Sounds about an 8" piece of 1/0 being able to stand 600A(I think it was) and not flashing the insulation off. I will go find it if someone wants. I used the specific heat explanation as well.

 

[Pioneer~Saturn 5,000+ posts]

Read that and commented as I recall. Heat generation, insulation breakdown. I squared R basically. Does that change the fact the length of the conductor has absolutely no effect? People here seem to think a short wire can carry more current than a longer wire (of the same size). This myth needs to be debunked.

I give up...

 

[smoka 10+ year member]

Not that it matters too much, but I'm also currently seeking a degree in electrical engineering. I'm in the Electrical and Computer Engineering Tech. program at Purdue. Two years down and two to go.

Cool. The 3rd year is usually the toughest. Good luck.

 

[McIntosh 10+ year member]

Considering you'll have a voltage drop of 531v, I don't think you'll make it.

If I started with 12 volts I've done quite well! I gained 519 volts! I should've started lower to gain even more.

 

[ejschultz 10+ year member]

I give up...

I don't think there's anything anyone can say. He needs to actually test it to see. I guess he's a "hands on learner." He needs to get that 20000 feet of 1/0 and put 265 amps through it and watch what's going to happen.

 

[ejschultz 10+ year member]

Cool. The 3rd year is usually the toughest. Good luck.

Ha, you're not the first to tell me that. Thanks though, I'll probably need all the luck I can get with my "obviously limited knowledge."

 

[MakeshiftAudio 10+ year member]

I don't think there's anything anyone can say. He needs to actually test it to see. I guess he's a "hands on learner." He needs to get that 20000 feet of 1/0 and put 265 amps through it and watch what's going to happen.

He's going to need a higher voltage than 12.8, as we've already discovered above. If he shorts a battery with that 20kft of wire, he will only draw some 83.3W from the batt. Nothing. Nor will there be a lot of heating.