# Rectification of 5 megaamps current

#### Just Another Sparky

Joined Dec 8, 2019
213
For perspective, the largest interrupting rating you'll probably ever see in a fuse is somewhere around 300kA. That sort of available fault current at the voltages you're talking about is typically only found directly off the secondary lugs of a 6~20 MVA transformer. If my math skills hold up, with a voltage of 1kV you're going to need a total circuit impedance of not over 200uΩ to achieve 5MA. For 5 feet of wire (2 wire circuit), that translates to 700KCMIL conductors - and this is without accounting for any sort of inductive reactance or the load/line characteristics. Pushing it to 10 feet would require 1250 or 1500KCMIL conductors - wire bigger in cross-section than a half-dollar coin! And the I^2R losses even at that would be near 100%.

Not only that, the magnetic forces alone from 5MA of current would rip your circuit apart in an instant!

And on the odd chance you really are working with currents above 5-10kA at 500 volts, you should probably be wearing a 40 cal flash suit! Arc flash is a shitty way to go.

Last edited:

#### jpanhalt

Joined Jan 18, 2008
11,088
For perspective, the largest interrupting rating you'll probably ever see in a fuse is somewhere around 300kA. That sort of available fault current at the voltages you're talking about is typically only found directly off the secondary lugs of a 6~20 MVA transformer. If my math skills hold up, with a voltage of 1kV you're going to need a total circuit impedance of not over 200uΩ to achieve 5MA. For 5 feet of wire (2 wire circuit), that translates to 700KCMIL conductors - and this is without accounting for any sort of inductive reactance or the load/line characteristics. Pushing it to 10 feet would require 1250 or 1500KCMIL conductors - wire bigger in cross-section than a half-dollar coin! And the I^2R losses even at that would be near 100%.

Not only that, the magnetic forces alone from 5MA of current would rip your circuit apart in an instant!

And on the odd chance you really are working with currents above 5-10kA at 500 volts, you should probably be wearing a 40 cal flash suit! Arc flash is a shitty way to go.

You need to think outside the box. Once you do that, solutions become obvious.

#### Just Another Sparky

Joined Dec 8, 2019
213
You need to think outside the box. Once you do that, solutions become obvious.
That's got to be a reference but it escapes me.

#### BobTPH

Joined Jun 5, 2013
3,507
Logic would dictate that, if things were as the TS states, he would be dead by now.

Bob

#### Javier Lopez 1

Joined May 21, 2019
8
Over 100kA "wires" are forbidden, only plasma and large bars must be used, if some hockey pucks SCRs are used must be installed directly on large aluminum, copper, or brass solid bars. In my first test, a thick cable disappeared, also a titanium bolt
It is impossible to stop that currents, so it must be stopped just when the current is zero before going negative

#### Just Another Sparky

Joined Dec 8, 2019
213

That's about what your circuit would look like if it were actually achieving 100kA... much less 5,000kA.
Here's 3,500kA... achieved by shorting out a pallet full of 18,000 volt high performance low-Z capacitors:

And so on and so forth;

Last edited:

#### schmitt trigger

Joined Jul 12, 2010
453