HPS 400 sufficient ? ... heat ?

[the image reaper]

I have grown exclusively with Flourescents for many years, 320 watts of 4-footers, because I just never wanted to deal with the heat put out by the sodium lamps ... but, I am thinking of experimenting with a 400-watt sodium at the next flower time ... my cabinet is 2ft x 4ft x 6.5ft ... would a 400w be sufficient , or just barely ? ... also, how much heat will the 400 produce ??, finally, how high above the plants would the 400-watt HPS need to hang ?? ... thanks in advance for answers :smokin:

[Sinsemilla Jones]

of the cab and you keep the room cool that the cab is in, you should hopefully be able to stay sub 90. Probably have to keep the ballast outside of the cab, tho. If your doing hydro, you might have to take measures to keep the water temp sub 78.

Start at a foot away and move in with the light, and use the back of the hand method - if you don't want to leave your hand there, you don't want to leave your plants there. If you blow a fan between the light and plants it will help get it closer.

400 is probably about as big as you want to go in a cab/closet type setup.

:thumbsup:

[karmaxul]

With a 400watt hps 300 watts produce the heat needed for illumination.
Its a 300 watt heater and a 100 watt light basically. How do they flower under the flouro tubes?
One love
c

[jamstigator]

My cabinet is pretty close to those dimensions (20" deep, 6' high, 4' wide), and I have a 400 watt HPS in it. The (digital) ballast is in there too. I have no problems with heat - I run 3-6 degrees higher than ambient, and it's not been difficult to keep it in the 75-77 degree range. I'd say the light is about right, but I also run eight 26 watt flouros in there for accent/sidelighting, for a total of 604 watts, and 65,000 lumens or so. I do use a cooltube and a 440 CFM 6" centrifugal inline fan (dialed way down speed-wise because that's an awful lot of fan power for my cabinet). You can get your plants quite close if you go the cooltube route - I've had no problems getting within 4 or 6 inches. But to provide better spread over the width of the cabinet I usually keep it a foot or 18" away.

400 watts isn't the highest you can go either. There was an interesting growlog on overgrow (R.I.P.) by a guy who had a really nice looking armoire about the same size as my cabinet. He put a 1000 watt light in there and had no problems. He did it knowing that that much light was way overkill, because he wanted to see if it was doable (it was), and because he already had the light laying around. Personally, I think a 400 is just about the right size, and any more than 600 would just be a waste of electricity.

[the image reaper]

yeah, I was thinking 400 would be about right, just will have to deal with the heat ... I have top-mounted exhaust fan, and floor-level intakes, but heat isnt an issue with my flourescents, I will need a better fan with the HPS400 .... regarding an earlier question, I had good results with 6x40watt tubes, potency-wise, but no large yields ... plus, now I am at 8 tubes, and weight of the light unit is a pain in the ass, so HPS400 looking better every day ... thanx for info ... :smokin:

newest cabinet, just finished it a few days ago ... 2' x 4' x 6.5'
eight 4' 40W 6 blue, 2 red now
will flower w/ 6 red, 2 blue
may buy HPS400

http://i15.photobucket.com/albums/a368/roadcam/935e1204.jpg

[karmaxul]

do you know the degree kelvin of the red or blue?

One love
c

[the image reaper]

the 'reds' are definitely 3000K, I believe the 'blue' were 6700K, if memory serves me right ... and you know how our memories are ... :stoned:

[the image reaper]

forgot to mention, the 'blues' are GE coolwhites, and the 'reds' are GE Kitchen and Bath , ... :smokin:

[karmaxul]

Cool thanks

One love
c

[karmaxul]

So 5466 (548nm) for veg and 4233K (708nm) flower. I like it. How big do they finish?

One love
c

[the image reaper]

I cant say for sure ... this is the first time I got specific about the 'color' of my lights ... I know this sounds wild, but I must have the world's best luck, because since 1977, I just bought the cheapest flouro tubes I could find, I would guess they were all 'blue' spectrum, these reds' look differently than I'm used to ... here's a real kicker: I have only had ONE male plant develop in my life ... so far ... hope I don't jinx myself ... this is also the first time I ever bought seeds, I always just used the seeds found in half-decent bags of street weed, only had an indica one time, all others just happened to be sativas, judging by their looks ... but I always had quality smoke from those grows, just not big on yield ... :smokin:

[MisterSource]

i am using a 400w HPS in a cool tube. i jigged up a stanley fan, and i can touch the glass and it's warm at best.

i have a thread in this forum with pics. Using MH for veg, and HPS for flowering.

[notanotherteensmoker]

hi...if you want a reference from a beginner who had to work with limited resources:

It sounds like you have ventiliation under control, but I didn't...

In an unheated bedroom, when the outside winter temperature in Northern California was in the 50s and low 60s, it ran anywhere from 78 to 82 degrees a foot or more under my 400w lamp.

When the outside temperature was unusually warm, in the 70s, the closet temperature pushed 90...all depending on how much the doors were cracked.

I had two oscillating fans, one angled over the top of plants and back toward the bulb, and another placed right next to the light, blowing heat away from the unit and back into the bedroom.

2 other possible factors building heat:

I switched to a MH conversion bulb with great results, but more heat
I used an Econogrow Mini with a built-in ballast, so heat was hard to dissipate.

It sounds like your setup should give you lower temperatures than I had.

And, as far as hanging distance, I kept mine 12 - 18 inches above the tops.

"Here's where my future quote will go"

[louisville97]

I agree totally with N.A.T.S. The room temperature has a dramatic effect on the inside temperature of your box. If the cabinet is drawing cool air, you would be okay. But if your room temperature is too high, like a little uncomfortable for people, then the inside of your cabinet could reach high
90's and even more. Been there Done that, but caught it in time before any major trauma affected my WW children. WHEW!

[the image reaper]

thanks for your response, but this is an OLD thread, things are already done now ... all is well :smokin:

[notanotherteensmoker]

All right, an abbreviation to N.A.T.S! Just when I thought I was going to have to re-register with a shorter handle! Thanks, louisville97! :)