Converting an old metal halide fixture into a grow light

Well hello again chaps. So I acquired a free 330 Watt metal halide lamp and I’m curious if and how I could make it a grow light.

The culpret:

First I’ll need to get a a new cord with a standard three prong outlet. Easy part I think.

Next, I’ll have to make a some type of reflector/hood that I can run my exhaust fan through for cooling.

Lastly, will any of this work or am I wasting my time? Lmao. Really hoping to get this working as it’ll save me hundreds on new veg lights.

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I wish I could help ya bro but I’m not an indoor lighting genius and I have never ran a HPS or MH bulb in my life lol. . . Hopefully more people will comment

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Haha it’s good dude. I’ve only ever used LED’s so this is new to me as well.

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Lol I’ve never ran leds either, well except my solar ghetto grow ones but I haven’t even done a full run under them yet so I still say I haven’t lol

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I know these are not exactly cheap, but I picked up the Ray44, best lighting investment I have made in a while.

https://2xuwao2gok1v2wn2em9n5ys8-wpengine.netdna-ssl.com/wp-content/uploads/2018/02/RAY-180215.pdf

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I would love to buy one but at the moment I want to save my money for Soil. :wink:

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If it works as is and lights up the bulp, it’s easy going from there.

You will just need to unbolt the screws and bolt, removing the cover where the fixture is mounted.

There should be two wires going from the ballast to the fixture, you will most likely be able to unscrew them.
Mount a flexible 3x1.5 mm2 (15-14 AWG) cable, this you can extend 3 meters and connect to a aircooled hood.
At that point you can fire up 400 Watt MH’s or HPS bulps, with out risk of fire or damage to the ballast.

Vertical lights have heat problems, when they hang socket top-wise. All the heat go directly up, into the socket.
Vertical growlights are often aircooled, and still it’s recommended to hang them so the bulp points up.

That looks like a vertical shoplights without the reflector, but the ballast is labled for more then 380 Watt.

Unscrew some things and let’s see how it looks inside!

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@99perCent I’m new to the forum very nice to meet u man I live in the UK and was passed some of ur crosses jumping Cindy’s and Space X can u tell me anything about them the time from seed to harvest and r the ey photo or autos cheers

I

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Top of the morning to you brother.

Jummp Cindy is a cross of (Jacked Up x C99) x (Agent Orange x [XJ13 x Penny Wise]) = Non-stabilized Poly-hybrid

Space X is a cross of Space Candy and the (Agent Orange x [XJ13 x Penny Wise]) = Non-stabilized Poly-hybrid

These are regular seeds. I have not run any of these yet myself. Hoping the JC will bring some fruit flavors and the Space crosses are all fairly robust. Plants in both crosses should yield lots of variety.

Make sure you post your thread when you are up and running.

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This may be the new thing I learn today. I thought as mine were in cooltubes with the heat from the bulb being drawn away from the socket end it would be fine.

What are the problems?

When the bulp is hanging in the socket, the air flow might cool the outside of the bulp.
But inside the bulp, the heat will go directly up into the socket.
The glue or what ever it is, that they fix the socket onto the glass with.
Over a few grows, it often becomes brittle and the gas inside the bulp will leak out or something.

I had bulps that died after 2-3, grows untill someone pointed this out to me, in an old verticval setup I did a long time ago.
It changed when I flipped then tubes, even tho I at first thourt it was BS. I had seen lot’s of 1000K bulps hang in the socket, but replacing bulps got borring. Having to get the broken socket out of the lampfixture, can be anoying as I had to unmount the fixture inside the cooltube… it was a PITA.

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In this setup, the top bulp suffered and the bottom bulp did not.

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Wait so are you saying mount the ballast else where and extend the socket? Or turn the whole thing upside down? I’ll take it apart tonight after work.

I had the impression you should open the ballast and find the two wires that lead to the socket then connect a longer wire to those electrical connections (noting which goes to the centre and which to the outside of the socket) so you can have the ballast away from the light outside your tent.

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I would remove the socket, hook up a new wire instead of the ones going to the socket.

Here is a old 600W Greenhouse light, that I converted into a remote ballat.
The bulp was original mounted, directly into the ballast.


Now the socket is gone tho.

Inside you have a electromagnetic coil (The big square thing), a capacitor (the cylendric part) and a igniter (The small square thing.

Just replace the wire from the ignitor, to the socket with a wire maximum 3 meters long. And be sure to use a 1.5 mm2 core wire, and there is no problem in doing this.
Be sure to connect the positive and negative side correct, but doing it wrong won’t harm the ballast or bulp.
It will just not light up, IME no damage done if your just testing it.

The new 3 meter wire, you can connect to any aircooled light from the grow store.
They also come with a cheramic socket and all, it’s just connecting the wire and screw in the bulp.

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You’re awesome dude thank you so much for the help. OK so now would I need to cool off the ballast as well or should most of the heat be from the bulb?

Your welcome!
All the real heat is gonna come from the bulp, the ballast will just get warm nothing that will cause any damage.
But if you have a small grow space, it can be a benefit to be able to place the ballast outside the room.
Or below the grow table for bottom heat, that is also a option if you have a uninsulated cold concreate floor.

I house my ballasts in the attic, even tho I now use electronic ballast that give off a little less heat then a magnetic ballast.

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Thanks for the info good sir anything with c99 in I’m a sucker for I only run a small room so need to make sure I’m planting fems is how I roll for now I need to maximize what room I av but as n as I pop a few Ill give u the heads up mate

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OK so I’m not entirely sure what that means, but is this the right type?
6’ 14-3 Lighting Fixture Whip at Menards https://www.menards.com/main/p-1444442917587.htm

https://www.menards.com/main/electrical/electrical-wire-cable/indoor-electrical-cable/14-gauge-nm-b-cable-with-ground-wire/147-1403a3/p-1474478926956.htm

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