Metal Halide - Remote Ballast Output Wire Requirements?

[Æonic]

Hi,

You'd think this would be mentioned everywhere, but I can't seem to find a definitive answer.

What is the required voltage rating and minimum gauge for the wire between a metal halide ballast and the lamp?

For voltage, I see most people using common extension cords rated at 300v or sometimes 600v. Is that within the maximum that a M-57 or M-58 (175w or 250w) ballast ever going to put out? I mean suppose at startup, or attempting to start a hot light, it outputs 800v, and at that same moment I happened to be holding onto the cord... with my tongue... whilst standing in a bucket of water. It could happen. Could I get shocked? I know these ballasts put out a wide range of voltages... but there has to be a safe maximum wire rating, right?

For wattage, it's less of a concern because a 175w system is probably not going to exceed what a typical extension cord can handle. But if I end up buying some special high voltage wire, it could matter. And I know it would depend highly on the lamp/ballast rating. Is there a chart somewhere?

Thanks!

 

[DustinB]

14 AWG stranded should be fine. I believe that is what most of them use anyway. The same wire that is used in computer power cords.

 

[Æonic]

Well, hmm. I have a computer power cord right here and it reads 300v. But according to this thread (RC), the voltage ratings for the lamp are all in excess of 300v (no info on what a typical ballast actually puts out though). However, I have never heard of anyone getting shocked by their MH setup, and I don't think I've ever seen a post from someone mentioning an internal short or insulation breakdown due to this either.

It seems odd to me that a company that makes MH equipment would use a cord rated for less than the voltage passing through it.

Maybe I'm mistaken about what the rating on a wire means, but I thought it was the maximum voltage that the insulation can contain without potentially arcing through the insulation at you, or to ground, or at the other conductor in the same wire.

 

[DustinB]

I'm not very well versed in the electronics behind ballasts, maybe someone with a bit more knowledge will chime in.

I do know that some people, myself included, have used computer cord extenders from icecap 250w ballasts to a fixture without issue. I can't comment on the voltages or insulation ratings.

 

[on the spot]

It's probably not safe (disclaimer) but I use the cable from the local hardware store. 14 gauge, 600v nickle plated copper strand. If you drive to Michigan, Godwin hardware will set you up. By the foot, they have huge spools.

 

[Humu Humu]

All of my MH cords read 600V 18gage.