Is there anyone here who can help me please,

i have a need to try an calculate the AC single phase Arc energy (230v - 20amps upto 470Amps at 50Hz)
I then need to replicate this "Arc energy" at DC at 220volts

Its a totally different application from switchgear and i know most of you would say its to low however i need to try and model this

thanks

Jas

Sorry, out of my league. Sounds like you need someone with the Canadian or European calculations.

Thanks anyway Martin.

i was wondering if i just used VA's, weather or not this would be representative in getting the idea across that an DC Arc is worse than an AC one.

say for instance we pick up load at 230v 420A 50Hz rms (ignoring vectors fro the time being)

That would be 96.6KVA however if the Arc lasted for 1.5s then 1/50 x1.5 = 0.03.
therefore 96600 x 0.03 = 2.9KVA for the duration of the Arc.

If i did the same test on DC (as the AC is rms so should be equivalent to DC)

230V x 420A = 96.6KVA

However with the Arc lasting a 1.5s this equates to 144.9KVA for the duration of the Arc.

so to get similar values at DC as those in AC

2900VA / 1.5 = 1933.3 / 420A = 4.6volts
or / 230v = 8.4Amps
so i think i need a different approach

( this is assuming that the distance and time it take to close the arc is constant)

Why 1/50 x 1.5? That's only 1.5 cycle, quite far from the original 1.5 second...

Ah! its always better to read a post first