400W HPS with 600W ballast - possible?

[sv4run]

I wonder if i could use 400W HPS with 600W Lumatek dig. ballast. I saw some posts where users mention some switch on ballast for lower watt lights. I only have some "Super Lumens" switch.

Maybe stupid question to some, but summer is near by and i already have problems with temperature in hot days. So i thought i could try 400W. But i don't want to spend more money on new ballast or damage my current one.

I found some debate about this on some other forums via google. Some say yes, some no.

So ...
What do you think, or better, know?

 

[guest845704]

400W ballast = 400W bulb
600w ballast = 600W bulb
400/600w if digital ballast have switch, 400W/600W

 

[krompir]

It will work.But only for a few minutes ,maybe hours. To much power from 600W ballast will burn your 400W bulb ,thats for sure.So if you dont have a switch for 400W on you lumatek, then i wouldnt do it.

 

[foomar]

Stuck a good quality 400 on a 600 once in error , lasted three weeks and was as bright as a 600 to the eye, eventually got so hot it melted the solder and failed.

At 50% over service load am suprised it lasted that long , absolutely not safe practice.

Have seen ballasts of 750 watts that run 600 w bulbs , so some overclocking is possible.

A 600 on a 400 ballast is safe but probably less efficient , and not all brands will ignite properly , or restrike after power cut.

 

[sv4run]

Thanks for replys.

So i will probably have to take a break during summer or maybe run AC during grow time so i won't have sauna in my apartment. Last week i had close to 35°C (95 F) in my cab at the end of 12/12 cycle and is not even summer.

 

[foomar]

Found that moveing the exhaust inlet close to the bulb dropped 10 deg , proper cooltube dropped another ten , might get you by unless you already do this , a larger fan might be the cheapest option to increase the air exchange rate.

 

[magiccannabus]

I am pretty sure some digital ballasts are built to accept a variety of lower wattage bulbs than the given rating. I think this is not the case for most ballasts though.

 

[joe guy]

You can only run a bulb that is rated higher like a 600 watt on a 400 ballast but you won't get the correct par the bulb was designed to emmit but never run a bulb that is rated lower than the ballast u run the risk of blowing the bulb up and as we all know they get hot as shit and that shatterd glass runs the risk of setting your carpet on fire... so stick with the ac idea and little bigger fan to move the hot air around... hope it helps a lil...

 

[joe guy]

Except as noted above unless the ballast says 400w. 600w and super lume then its safe to run the 400 if switched to the proper wattage. Not sure where ur from but I've gottn all my grow gear from craigs list super cheap if being brand new in the box dosnt matter to you then there is huge savings to be had hate to say it but alota people need rent money and are willing to price shit to sell that day.. best time is about a week b4 the end of the month.. so its somthing to look up.. good luck and hope it works out hate to hear a fellow grower have to shut down cause the heat

 

[sv4run]

Thank you all for your post.

Today i tried to run AC to see how low i can push it. Well, i started 7 hours into 12/12 cycle, so i could probably push it lower if i would start AC with 12/12. It went from 31-32°c to 27,5-28°C.

 

[Hüsker Dü]

Buy the right equipment.
Do not experiment.
Do not compromise.

Life is priceless....


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