# 600w bulb with a 400w ballast?



## Green Troll (May 21, 2012)

Might be a silly question but does this work? I understand the other way around will blow the bulb but under powering a 600w bulb, will it glow like a 400w? Or would it just sit and blink because it isnt getting enough power? It is just i am getting a 600w light soon, and i will only need a 400w Sodium for one flower stage and i didnt want to waste the money on a bulb i wont use again if i didnt have to. The ballast is digital.


----------



## drolove (May 21, 2012)

from my understanding no it wont work because it wont fully light the bulb and therefor not giving you the right color temp. hope that helps ya man. GOOD LUCK


----------



## Gastanker (May 21, 2012)

You can run a 600w bulb in a 400w ballast and it will fire and put out 400w of light but the spectrum will be compromised. I would recommend you purchasing a cheap $10 400w bulb to use with your 400w ballast until your new light comes in.


----------



## 209 Cali closet grower (May 21, 2012)

Gastanker said:


> You can run a 600w bulb in a 400w ballast and it will fire and put out 400w of light but the spectrum will be compromised. I would recommend you purchasing a cheap $35 400w bulb to use with your 400w ballast until your new light comes in.


fixed.

just run the bulb, till you can get the right one.Been there, done that.You will be fine.

People with dimmable ballast do it all the time.


----------



## drolove (May 21, 2012)

209 Cali closet grower said:


> fixed.
> 
> just run the bulb, till you can get the right one.Been there, done that.You will be fine.
> 
> People with dimmable ballast do it all the time.



ehhh.....i dont wanna say it wont work, but ide just buy a cheap temporary bulb in the right size


----------



## Gastanker (May 21, 2012)

209 Cali closet grower said:


> fixed.
> 
> just run the bulb, till you can get the right one.Been there, done that.You will be fine.
> 
> People with dimmable ballast do it all the time.


Cheap bulbs are really cheap. Here's a philips which is actually a brand name and of fairly decent quality $12 and they are even cheaper at your local home depot - http://1000bulbs.com/product/4752/LU0400-368811.html?utm_source=SmartFeedGoogleBase&utm_medium=Shopping&utm_term=LU0400-368811&utm_content=400+Watt+-+High+Pressure+Sodium&utm_campaign=SmartFeedGoogleBaseShopping&gclid=CPS7zaD9kbACFWsZQgodyT_npg

Work fine for growing plants.

Of course your point is very valid. I run my 600w MH bulb almost exclusively at 400w and have no problems. More you dimm it more the spectrum gets fucked though.


----------



## ScoobyDoobyDoo (May 21, 2012)

i used to run my 1000w bulbs at 600w till i talked to the guys at hortilux, lumatek, and my grow shop. they all said the same thing. it's not worth it. it will actually shorten bulb life and it dies change the spectrum of light. you can do it in a pinch if you have to. i don't think running it like that for a week or so will make that big a difference but like these guys said, get yourself a cheap 400w bulb when you can.


----------



## 209 Cali closet grower (May 21, 2012)

Gastanker said:


> Cheap bulbs are really cheap. Here's a philips which is actually a brand name and of fairly decent quality $12 and they are even cheaper at your local home depot - http://1000bulbs.com/product/4752/LU0400-368811.html?utm_source=SmartFeedGoogleBase&utm_medium=Shopping&utm_term=LU0400-368811&utm_content=400+Watt+-+High+Pressure+Sodium&utm_campaign=SmartFeedGoogleBaseShopping&gclid=CPS7zaD9kbACFWsZQgodyT_npg
> 
> Work fine for growing plants.
> 
> Of course your point is very valid. I run my 600w MH bulb almost exclusively at 400w and have no problems. More you dimm it more the spectrum gets fucked though.


well for that bulb, it came out too $24 with shipping, which is still a good deal.

That bulb at my work cost $33 out the door.


----------



## drolove (May 21, 2012)

ScoobyDoobyDoo said:


> i used to run my 1000w bulbs at 600w till i talked to the guys at hortilux, lumatek, and my grow shop. they all said the same thing. it's not worth it. it will actually shorten bulb life and it dies change the spectrum of light. you can do it in a pinch if you have to. i don't think running it like that for a week or so will make that big a difference but like these guys said, get yourself a cheap 400w bulb when you can.


oh! forgot to mention that as well! ive read in multiple places it'll shorten bulb life


----------



## Josh27glock (May 21, 2012)

been running a 750 watt hps bulb in a 400 watt digital ballast for a long time in veg room, havent noticed any difference in growth compared to a 400 watt bulb. seems like the same thing as running a dimmable ballast. thr 750 watt bulb centers better in my cool tube than a short 400 watt bulb.


----------



## Green Troll (May 22, 2012)

Thanks guys. I think i will just buy a 400w bulb. The spectrum issue worries me as it will be at flower stage and i dont want to lose yield because of it. I wont buy a cheap one, i will always buy the best, but i will maybe get to use it again one day =) They are about £30 and i am sure using the right bulb will get me a few more grams of goodness to pay for itself.

Rep to you all.


----------



## polyarcturus (May 22, 2012)

it will work as gastanker said compromised spectrum underpowered HPS will become more yellow. you can buy a cheapo bulb if you only need it once.


----------

