Bulbs

[growell]

Can i use a 600watt hps bulb in a 400watt ballast and light anyone know thanks guys

[Xena]

Just speaking as a guy with a construction/electrical background I would say no.

[buds73]

I wouldn't put a 400w in a 600w ballast that would probably blow your bulb but the other way round as you've asked i would say yes probably but the ballast will only give you 400w so your bulb would run with only 400w. That would probably mean that your bulb would be much dimmer than it should be and i would have though that could change the spectrum although i'm not sure about that.

[growell]

Thanks guys as long as nothing blows that what i dont want to happen i trying to change all bulbs metal halide for veg hps for flower and i just fell across a 400watt ballast and shade but got know 400watt bulbs thanks for replys guys

[buds73]

Shouldn't blow anything. Way i see it you can get dimmable ballasts.All they do it lower the wattage going out from the ballast to the light. 400w is under-powered for a 600w bulb. Should be like running a 600w ballast dimmed down a third.
p.s is dimmable a word? iv'e had a smoke and it just don't look right lol

[growell]

Ye mate that is a word haha

[buds73]

Thanks. thought i was losing it lol

[ChadWestport]

This would not be an effective choice. The ballast does not provide enough wattage to properly light the pressurized gas inside the bulb, meaning even if it shines, it won't be the desired or intended spectrum for optimal plant growth. The mismatch in wattage is enough to stop me, but the above is a scientific reason.

[growell]

Cheers mate it was a short term thing till i got a 400watt bulb i will probably just wait now i have heard peoples comments so nice one

[ChadWestport]

Cheers! I replace bulbs once or twice a year, but usually hold onto one of the old ones incase I have an outage and can't get a new bulb for a few days / week. I've also had to stuff my flower tent with lamp bulbs once..... after that I started holding one of the old bulbs

[dphipps1020]

I have a 1000W bulb running at about 375W and it's working just fine. Been running it that way for a few months now with no issues.

[ChadWestport]

Are you using a digital dimmable ballast?

[dphipps1020]

Yeah it's a 750W ballast dimmed to 50%

[growell]

How are u running the bulb through what

[dphipps1020]

The reflector hoods are usually rated to handle up to 1000W bulbs and ballasts from what I've seen, so they can fit whatever wattage bulb you put in it. The ballast is the part that actually matters because that's what controls the wattage. As long as your ballast wattage doesn't exceed your bulb wattage, you shouldn't have to worry about a blown bulb or otherwise. I hope that made sense.

[ChadWestport]

Digital ballasts have specialized electrical stepping that makes what you are describing possible. But that doesn't mean your higher wattage bulb is going to run proper from the lower wattage. Check out this article which explains it better - https://growlightinfo.com/should-i-dim-my-ballast/

[dphipps1020]

Yeah I understand that part too. I've been running mine like this for about a year now with no issues yet so I've stuck with it. Too much more wattage and my heat gets out of control.