• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

surge current of wires

Frosty_47

New Member
Hello,

I would like to know if there is a chart that lists the maximum surge current of AWG wires. I am close to finishing my 4000 Joule 1600V capacitor defibrillator and would be inconvenienced if the wires explode/melt away.

-Thanks
 

Pommie

Well-Known Member
Most Helpful Member
OK, I'll go along with the joke. A 1 thousandth of an inch diameter wire will easily carry 4000 joules without exploding or melting away.

Now ask a sensible question.

Mike.
 

Frosty_47

New Member
Ermmm I aint volunteering as his patient....:)
Why not ? I mean isn't there a hefty prize given to the family of a Darwin Nominee ?
 

tcmtech

Banned
Most Helpful Member
Do you know the estimated discharge time? A joule is one watt second. If you dump it all in one second that the same as a 14.4 mega watt load at 1600 volts or about 9000 amps for one second.

Two 4/0 welding cables can take that kind of burst. they can hold a continuous duty 1000 amp submerged arc welder without trouble. Even with 20 KA peaks I doubt you would bother them one bit.
 

Chippie

Member
Do you know the estimated discharge time? A joule is one watt second. If you dump it all in one second that the same as a 14.4 mega watt load at 1600 volts or about 9000 amps for one second.

Two 4/0 welding cables can take that kind of burst. they can hold a continuous duty 1000 amp submerged arc welder without trouble. Even with 20 KA peaks I doubt you would bother them one bit.
Cor!...some firework display if you shorted the leads... :)
 

Hero999

Banned
I hate meausing cable in AWG or SWG. Cross-sectional area mm² is much easier to understand.

So you're building a defibrillator; how do you plan to spend in getting it approved?
 

tcmtech

Banned
Most Helpful Member
At 4000 joules and 1600 volts its not a defibrillator. Its a vaporizer!:eek::D
Still, I would play with it!
 

Willbe

New Member
Onderdonk vs. Preece

16 gauge copper wire: Tmelt = 1083, Area = 2581 circ mil, Time = 5 sec, Tamb = 25

E= Area in CM
B = Tmelt - Tamb in deg. C
D = 234-Tambient in deg. C
T= time in seconds.
So, E = 2581, B= 1058, D=209, T=5
Then
Ifuse = E* SQRT {<LOG[(B/D)+1]>/(T*33)}
Ifuse = 2581* SQRT {<LOG[(1058/210)+1]>/165}
Ifuse = 2581* SQRT {<LOG(6.04)>/165}
Ifuse = 2581* SQRT {0.781/165}
Ifuse = 2581* SQRT {.00473}
Ifuse = 2581* 0.0688
Ifuse = 178A
 
Last edited:

smanches

New Member
So that's 178A for 5 seconds to hit the melting temp?
 
Last edited:

Hero999

Banned
What about the insulation?

The plastic/rubber insulation will burn up long before the conductor vaporises.
 

Chippie

Member
Jeez....I have a Tens machine for pain relief and thats enough for me....178Amps...boy you can weld with less than that....
 

EE World Online Articles

Loading

 
Top