High-Power Grow Lights (250-400W): Installation Tips and Other Advice?

January 15, 2004 12:59 AM

botanical / electric

I want to set up some high power grow lights, like 250 - 400 watt HPS. Any one know how to install something like that? Would anyone wise in the ways of wiring suggest an amateur even attempt something like this? I don't wanna get electrocuted.

posted by Tryptophan-5ht to home & garden (8 comments total)

Are you going to do this inside your house? Watch out for a drastic rise in your power bill, and cops pointing infra-red radiation detectors your way from all directions...

In any case, they're going to be sucking some serious amperage, that's the main thing. Make sure you do your calculations and have heavy duty cables, and make sure your house's internal wiring / fusebox can handle the load. Those are the main areas you might have to talk to an electrician about.
posted by Jimbob at 3:01 AM on January 15, 2004

Seems the odds are against me.

Im trying to grow a tropical 'sunflower' that grows on the slopes of a dormant volcano in Hawaii. They are notoriously hard to keep alive. Im thinking if i can get enough 'sun' on them and simulate the drastic weather conditions, I can cultivate one.

So just in terms of lighting, do you know of any better alternatives? I need a lot of blue and green band.

If i cut it to just a 250 watt HPS bulb, do you suppose my 'standard middle class home's wiring could handle that kinda load?

Cops don't worry me - if i was ever searched, they'd leave disappointed. :-T

"talking to an electrician" - So i don't even want to try to wire this myself?

Also, i was told that i could expect an $80 yearly operating cost for a 400 watt high pressure sodium bulb. If you were to guess - what kind of spike should i anticipate? wouldn't a 400 watt bulb of any sort eat the same as 4 100 watt bulbs - or am i completely ass backward?
posted by Tryptophan-5ht at 4:10 AM on January 15, 2004

I need a lot of blue and green band.

Have you looked into metal halide lighting? There are a lot of fixtures and kits out their designed for marine aquariums, with peaks in the blue end of the spectrum. You can purchase complete systems with no wiring required. They are expensive though. Expect to spend $200-$800 USD.
posted by piskycritter at 4:41 AM on January 15, 2004

A simple Google Search throws up at least a couple of informative sites.

Micro Climes & Green Coast Hydroponics.

It all looks pretty uncomplicated to me: attach transformer to ordinary ~240 volt mains.
The main thing you need to be sure of is the load bearing capacity of your house wiring. If it can handle, say, an electric radiator or other mains heaters (which come in values of 500 to 1500+ watts) then you'll be ok with a 400 watt bulb.
posted by Blue Stone at 4:41 AM on January 15, 2004

How many lights were you planning on Tryp?

I was just talking to my father about this, as he knows about matters electrical, he said that standard, up-to-shape house-wiring would be fine for one 400 watt lamp. Not so for, say, ten.
posted by Blue Stone at 5:03 AM on January 15, 2004

wouldn't a 400 watt bulb of any sort eat the same as 4 100 watt bulbs

Yes. Your electrical circuits can probably handle 15 - 20 amps / circuit (check your circuit breakers / fuses, they should say how many amps they can handle). 400 watts (the light) / 110 volts = 3.63 amps for the light. Won't be any problem.

I've had a 400 watt HPS, a 250 watt MH, and a bunch of florescent lights all on one 15 amp circuit with no problems.

I need a lot of blue and green band

Like pesky said, check into Metal Halide. HPS has lots of red, MH has lots of blue light.
posted by Sirius at 6:39 AM on January 15, 2004

There are many sources of information about indoor lighting available when you consider that the needs of one tropical 'sunflower' pretty much mirrors the needs of another, more popular, tropical plant.

Overgrow
Natureshigh
Weedgrow

Also, one thing to consider that is often overlooked is that HPS lighting generates a great deal of heat that has to be properly vented. This residual heat is easily detected from the air and coupled with a drastic rise in your electrical use can provide probable cause for investigation. Insulation is critical and basements almost always better than attics.

Remember, these lights are going to be on for 16-23 hours a day during vegitative growth.
posted by cedar at 7:47 AM on January 15, 2004

all of the suggestions and information *greatly appreciated*

thanks :)
posted by Tryptophan-5ht at 10:39 AM on January 15, 2004