Ballast needed for metal halide bulbs.

I got a whole bunch of metal halide horticultural bulbs (175/250 w), with an E39 socket.

I see so many options for ballasts, do I need a transformer/capacator/resistor - kit - or one of the "digital" ones?

I have LED lighting, but would like to fill in wiht some of these MH bulbs.

Thanks

Don't know, I only know a HPS ballast wont work. It has to be a Metal halide ballast, if that helps.

Modern digital (electronic) ballasts usually fire and run both.

There are switchable magnetic ballasts that run both hps and mh.

Or you can buy a metal halide mag ballast but I haven’t seen them lately.

They will be watt specific. Some digital run multi wattage. They are dimmable.

Those kits you mentioned would be the cheapest way to do it. Good ol diy.

MichiganMedGrower said:

Modern digital (electronic) ballasts usually fire and run both.

There are switchable magnetic ballasts that run both hps and mh.

Or you can buy a metal halide mag ballast but I haven’t seen them lately.

They will be watt specific. Some digital run multi wattage. They are dimmable.

Those kits you mentioned would be the cheapest way to do it. Good ol diy.

Click to expand...

I'm sure that's more correct cuz I'm way back before digital. But I'm also thinking the kit mentioned transformer, capacitor and resistor, so that is not digital, and unless you know better I would recommend you need instructions for building a kit that specifies it is for metal halide, not hps. I'm a little leery of taking random bulbs if you don't know what they were paired with. I'm gussing kit should say it's specific for your E39 socket. I'm no expert with electronics, all the more reason I'd say do this. I don't know the difference between MH and HPS ballst for sure, but I think it probably is because the impedence of the two metals is difference. This means the impedence of the ballast has to be balanced to whichever bulb you got, meaning different size capacitors, etc. And maybe the socket type effects the bulbs impedence too, and I don't know what else.

And if you do it wrong at worse it may explode and even if it lights it doesn't mean it's well balanced and could be wasting electricity or burning too hot. Plus old bulbs still light for several years but are already compromising your capacitors.