Two bulbs per ballast?

[Dawg56]

I've looked in some electrotech forums and now I'm more canfused than ever!
Has anyone ever run two bulbs on one ballast at the same time? I'm wondering if it's possible to run two 175W bulbs off one 400W ballast, and would the bulbs necessarily have to be wired in series or in parallel?
Anybody ever had strech things out like this?

Dawg56 Reviewed by Dawg56 on 04-06-2010. Two bulbs per ballast? I've looked in some electrotech forums and now I'm more canfused than ever! Has anyone ever run two bulbs on one ballast at the same time? I'm wondering if it's possible to run two 175W bulbs off one 400W ballast, and would the bulbs necessarily have to be wired in series or in parallel? Anybody ever had strech things out like this? Rating: 5

[killerweed420]

I suppose its possible. I know there is a manufacturer that sells a ballast that will run 2 600w lights.

[Dawg56]

The problem is that I need lighting for a veg area. Currently I have two ballasts running two 400W MH lights in my grow room. One ballast is rated at 1000W, the other at 400W. I have two 175W Multi-vapor bulbs, so as you can see by the math, (2x400W bulbs on the 1000W ballast, 2x175W bulbs on the 400W ballast) I could solve my problem. I'm just not ready to experiment and risk screwing up my current grow!

[Rusty Trichome]

If you are not an electrician, (obviously you're not) I wouldn't dick with the ballasts. Fire and electrocution are a definate possibility if you screw-up.

I'd use the 175's for either side lighting, or perhaps in a seperate clone-n-seedling closet.

[Dawg56]

If you are not an electrician, (obviously you're not) I wouldn't dick with the ballasts. Fire and electrocution are a definate possibility if you screw-up.

I'd use the 175's for either side lighting, or perhaps in a seperate clone-n-seedling closet.

Thanx, I took your advice and built a small veg closet. I found a couple of street light "heads", and used the ballasts and fixtures. I probably could have electrocuted myself with less effort, but I'm liking my little closet a lot!

[seventhchild]

Thanx, I took your advice and built a small veg closet. I found a couple of street light "heads", and used the ballasts and fixtures. I probably could have electrocuted myself with less effort, but I'm liking my little closet a lot!

is that the 'street light head' in the center? if so i'm thinking it is a mercury vapor not a MH.if i remember correctly[not sure i do]a mv does not have a capacitor in the circuit and puts out a very poor spectrum for growth.

[seventhchild]

175watt is the most common size of mercury vapor lamp.

[Dawg56]

is that the 'street light head' in the center? if so i'm thinking it is a mercury vapor not a MH.if i remember correctly[not sure i do]a mv does not have a capacitor in the circuit and puts out a very poor spectrum for growth.

That's a fan in the middle. One of them came with a MH bulb in it, the other one was bulb less. Therefore, having realized that I have "assumed" what kind of ballasts they were, I feel like I've properly exposed myself as an idiot.
Having said that, these ballasts appear to be nothing more than a transformer of sorts. Yes, they do fire up MH bulbs, but the SLIGHTEST draw of power stops the arc, and they won't burn without shutting the power to them off, then restarting. Before the "awakening" that they were most probably designed for mercury vapor, I changed course because I thought reliability was the issue. Having read some on cfl's, and the fact that Wal-mart has a sale on Chinese built cfl's for $.92 each, I bought a bunch, and with an old six bulb bathroom fixture, we re-engineered the grow box a little.
At present, I have six 19 watt bulbs which are rated at 1200 lumens with a color temp. of 2700K. The floor of my box is approximately 18 inches by 30 inches. Also, I realize that for vegging, 6500K bulbs are needed, but should I replace, or add?

[seventhchild]

if heat control is not an issue i would add 65's