If I want to run my 250 Watt MH lamp on this, I would have to switch to the 250 Watt dim setting, right?
It just says "400 Watt", But it talks about 250 Watt settings.
Is it also safe to run my MH bulb unprotected in our fixture?
What's the risk of explosions?

If I want to run my 250 Watt MH lamp on this, I would have to switch to the 250 Watt dim setting, right?
It just says "400 Watt", But it talks about 250 Watt settings.
Is it also safe to run my MH bulb unprotected in our fixture?
What's the risk of explosions?

That will run 250w halides just fine. However, if it is going to be in an open fixture, use a protected lamp. Are you growing something you shouldn't be? 

Quote from: wattMaster on June 02, 2016, 03:05:41 PM

If I want to run my 250 Watt MH lamp on this, I would have to switch to the 250 Watt dim setting, right?
It just says "400 Watt", But it talks about 250 Watt settings.
Is it also safe to run my MH bulb unprotected in our fixture?
What's the risk of explosions?

That will run 250w halides just fine. However, if it is going to be in an open fixture, use a protected lamp. Are you growing something you shouldn't be?  

No, Just some tomatoes, and a couple other plants I can't remember.
We were afraid to use the superlumen mode because we thought it needed special lamps.
Would a big sheet of plastic be fine to contain explosions?
I'm just testing my 250 Watt MH lamp for just a couple of minutes.

As long as the plastic is at least 3mm thick, it will be fine.

As long as the plastic is at least 3mm thick, it will be fine.

And where do I get such plastic?

That Lumatek ballast operates the lamp on high frequency which isn't ideal and may actually increase the risk of rupture compared to 60hz operation. Also the "superlumens" setting drives the lamp at about what you'd get from a 400w magnetic ballast, which is completely fine. An electronic ballast such as this one operates a 400w lamp at exactly 400w, a magnetic ballast will always overdrive slightly. Also, regarding the lens, if the fixture/reflector includes the lens then thats all you need. If not, ide rather find an "O" rated lamp than trying to fabricate a lens from sheet plastic. Most styrene and acrylics will yellow and become brittle over time. Polycarbonate or UV cured acrylic is what you'd need.

That Lumatek ballast operates the lamp on high frequency which isn't ideal and may actually increase the risk of rupture compared to 60hz operation. Also the "superlumens" setting drives the lamp at about what you'd get from a 400w magnetic ballast, which is completely fine. An electronic ballast such as this one operates a 400w lamp at exactly 400w, a magnetic ballast will always overdrive slightly. Also, regarding the lens, if the fixture/reflector includes the lens then thats all you need. If not, ide rather find an "O" rated lamp than trying to fabricate a lens from sheet plastic. Most styrene and acrylics will yellow and become brittle over time. Polycarbonate or UV cured acrylic is what you'd need.

I'm not trying to make a lens, Just a temporary safety cover as insurance if it happens to explode.
So should I use the superlumen setting for testing my lamp?
And I'm not concerned about UV degrading plastic, It's just going to be used for a couple of minutes.
Are you talking about a lens for a permanent fixture, Or is it just another word for safety cover,
And I'm just thinking of the camera type lens?

Unless the lamp is at or beyond EOL the chances of it exploding are so incredibly small its basically nil. You have better chances of a well used mercury lamp exploding than a new or lightly used MH. The "superlumens" setting only applies to the rated 400w lamp and will drive at about 415w-420w, about what a magnetic ballast does. DO NOT operate a 250w lamp on anything other than the 250w setting. I honestly wouldnt run the 400w lamp on the 250w setting even though the ballast will do it, as it will only be running at partial discharge and therefore a greenish color. Also the 400w lamp cannot be dimmed to 250w while the lamp is operating, when you switch to 250w the lamp will extinguish (ive tried it). It has to be started on the 250w setting.

Unless the lamp is at or beyond EOL the chances of it exploding are so incredibly small its basically nil. You have better chances of a well used mercury lamp exploding than a new or lightly used MH. The "superlumens" setting only applies to the rated 400w lamp and will drive at about 415w-420w, about what a magnetic ballast does. DO NOT operate a 250w lamp on anything other than the 250w setting. I honestly wouldnt run the 400w lamp on the 250w setting even though the ballast will do it, as it will only be running at partial discharge and therefore a greenish color. Also the 400w lamp cannot be dimmed to 250w while the lamp is operating, when you switch to 250w the lamp will extinguish (ive tried it). It has to be started on the 250w setting.

There's also a 250 watt superlumen mode.

Oh, then you have a different model than I have, mine is an older 1st generation of the dimmable version (250w, 400w, Superlumens (400 only))

And could it be used as a regular ballast for a regular fixture?

yes it can, however the largest pitfall to high wattage electronic HID ballasts is their sensitivity to heat, making them unusable for any application where the ballast is mounted inside a non-ventilated fixture with the lamp, such as any waterproof outdoor flood like a parking lot fixture. This is why electronic ballasts over 150w are basically non-existent in the commercial and industrial lighting markets, but are super popular in the hobby markets like horticulture where every fixture is remote-ballasted.

So in short, only use this Lumatek in a remote application, and if it is enclosed in the same fixture as the lamp, the fixture should be fan cooled.

yes it can, however the largest pitfall to high wattage electronic HID ballasts is their sensitivity to heat, making them unusable for any application where the ballast is mounted inside a non-ventilated fixture with the lamp, such as any waterproof outdoor flood like a parking lot fixture. This is why electronic ballasts over 150w are basically non-existent in the commercial and industrial lighting markets, but are super popular in the hobby markets like horticulture where every fixture is remote-ballasted.

So in short, only use this Lumatek in a remote application, and if it is enclosed in the same fixture as the lamp, the fixture should be fan cooled.

If it is a high frequency, then you should never put it remote (with wires longer than about 50cm or so).
With others the limit is usually about 2m (limited by the ignitor).
Generally always observe the maximum cable length limit for the lamp <-> ballast connection.

Medved, this ballast's only recommended application is remote, and the manufacturer also lists ballast-to-lamp distance of 20'. Electronic ballasts start the lamp a little differently than magnetic pulse start, im not sure of the specifics on how it works, but ive read its equivalent to a 6.5Kv ignition pulse, but without that high of a voltage, I think the HF may play a role.

Also Ive seen large installations of these Lumatek ballasts where the cable distance between lamp was greater than 20' and pulse start lamps still fired up reliably. I understand the HF operation and long distance of cable between ballast and lamp isn't a good idea, but these are clearly designed for remote operation.

An alternate solution for a flood light outside would to have the ballast inside (Where it is Air Conditioned, I hope) and the MH bulb outside.