input output power

[bullseye]

hahaha!

[chuffer]

It all gets very messy with inductive/resistive loads, whether the load advances or lags. With AC its usually more appropriate to talk about VI rather that W.

 

But Baron if I can take a guess at what you're chasing: a broad idea of how much light you're gonna get, and how much power that draws to deliver:

 

The rating on your bulb is just a compliance plate, there so that folk can quickly add up the load of several appliances and check that they are within their specified limits. That means its almost always going to state tha it draws more power than it really does - just so you don't sue if circuits overload etc. So you can work with the compliance plates if all you are doing is checking that you aren't going to be overloading your powerboards etc.

 

If you want a rough idea of how much power your system is going to draw then its ok to work on your 48w cfls drawing about 48w each (they're fairly stable in what they draw despite varying bulb running temperature and varying supply voltage, as there's a feedback on the electronic ballast that should keep them at about the same power consumption regardless.

 

If you want an accurate idea on power draw you need to do measuring, as per previous posts.

 

Anyway that should sum up the electricity consumption side of things.

 

 

Now down to the problem of output - your light: light is done in Lumens, the lumens the manufacturers publish for your bulb are (supposedly) the amount of light that comes out of the bulb so it would be reasonable to assume that from lumens and power consumption you could make an accurate comparison of efficiency of differing bulbs but sadly, that's not the case.

Different types of bulbs (HID, HPS, CFL etc.) give out light at differing amounts on differing freqencies, so 100 lumen from a cfl is quite different to the same number of lumens from an HID.

 

And now it gets even nastier, because what the light does to your plant is not the same with differing bulbs either! So a 100 lumen of red will do different things to your plant than 100 lumens of yellow.

The further you look into it the more complex it gets, which is either fascinating or revolting, depending upon your point of view.

Reading over this post I had set out to clarify things but I realise that I've only further muddied the waters - sorry. My head hurts, I need a smoke...

I hope that some bits of this were useful, just ignore the rest.

[BaronS]

you want muddy Mr Waters?

 

Type Wattage Lumens Kelvin US$ "Lumens

per watt"

Gro Pro CFL 105 6200 5000 40 59.05

ACF CFL 200 12800 5000 85 64.00

Green Thumb CFL spiral 40 2650 5000 37 66.25

Green Thumb CFL spiral 40 2650 2700 37 66.25

ACF CFL 125 8500 2700 55 68.00

ACF CFL 125 8500 6400 55 68.00

250 MH Conversion 250 19000 38 76.00

2' T5 Light Strip 24 2000 6500 10 83.33

2' T5 Light Strip 24 2000 3000 10 83.33

250 MH 250 22000 24 88.00

400 MH 400 36000 25 90.00

400 MH Conversion 400 36000 39 90.00

4' T5 Light Strip 54 5000 6500 12 92.59

4' T5 Light Strip 54 5000 3000 12 92.59

600 MH Conversion 600 57000 69 95.00

220 HPS Conversion 250 25000 39 100.00

1000 MH 1000 111000 45 111.00

360 HPS Conversion 400 45000 45 112.50

250 HPS 250 28500 21 114.00

1000 MH Conversion 1000 119000 69 119.00

400 HPS 400 50000 22 125.00

940 HPS Conversion 1000 130000 169 130.00

1000 HPS 1000 140000 55 140.00

600 HPS 600 92000 49 153.33

[chuffer]

Thats very useful info Baron, thankyou

[BaronS]

what I gotta do now is look at the light charts for the various types and compare to 'useful light'. Figure out the expected 'useful lumens' from each.

 

There's other factors too. Something important to me is that I'm working in small spaces 550*850*1000 for 18/6 and 550*850*1400 for 12/12. In a bigger space many high wattage lights could be used but in such a small space there are benefits to spreading out smaller wattage units. Heat is also more easily dealt with in a larger space.

 

Basically, I'm trying to figure what's right for me, but as that causes me to collect information potentially useful to others I may as well throw it up for discussion.

 

Though MH/HPS seem, from the table, to give better bang for buck I'll probably stick with CFLs.

I'm concurrently looking at media but for now am going simple 'soil-like substance' in a pot.

 

Was it Anthony Horden?

As I live I grow.

[chuffer]

I'll be very interested to see what you come up with. I had a similar problem to solve, and my grow area is constricted at about .5 x .5 x 1.5m high so not only small space to work with, but I needed efficiency so I didn't get too much in way of overheating problems.

In the end I settled for 2 x 55w cfl at 6400K, and also a 90w UFO LED, 8:2 ratio red 660nm and blue 460nm. LEDS get canned here and other places (probably for good reason) so I feel I'm pretty much on my own unless it works. Anyway with such tight space constraints I've heard of others using just cfl and accepting a smaller/inferior harvest, so I feel that if the LED improves cropping for the paltry 90w it draws, then I shall be happy.

I don't get to collect my seeds for another few weeks so I'm test driving everything on some seed cherry tomatoes. So far the growth has been really great; the plants bushy with big leaves, less than an inch between vertical branches and heaps of lush plump tomato smell (only problem so far the original pairs of leaves have started curling and turning yellow, I dunno why). I know the real test for LED is whether or not they are any good for flower, but at least the signs so far are I should get good veg from them.

 

I confess I'm keen on the idea of using a cheap/efficient main light source and then just filling in the spectrum gaps with exotic stuff if needed hence my system; I like the very specific wavelengths available with LED.

 

At risk of drawing plenty of flak I hope to do a LED grow diary when mj seeds arrive but I'm also happy to chat about what I'm learning with lights on less interesting plants at the moment.

 

Once again I look forward to seeing how your calculations come out, the lighting system (hybrid?) you construct and how it runs in a small space

 

Oh on growing medium - the hydro shop dudes convinced me to go with coco, but I feel that it doesn't drain properly and I fear that if my ventilation becomes inadequate then I'll get a mould problem; so when it comes to the real grow I'll try a tip thats been posted around here and mix it 50/50 with perlite

 

Cheers