8' Fluorecent Tubes

K2

I'll try.
Ballast input is a real number. 280 watts= 2.3 amps at 120 volts. that's the electricity going through your meter and what your going to pay for. The lamp wattage is a comparison to some older lamp ballast setup somewhere. It's only a reference. Light output is not measured in watts it's measured in foot candles, lumens, candle power and a few others. Light meters for lighting I've used measure in foot candles or the metric lux.

It would be interesting to get a meter reading before you get your old lights down and then after you get your new ones up. I'm guessing your in the 25 ft candles range now and after you'll be in the 50+ range when your done.. .. Some old camera light meter could probably give you a good idea.

Leo G

That would have been interesting to take the two measurements. I wish I had a light meter. I have a camera but it wouldn't give a number reading. The HPS are pretty bright. Still hoping that only 2 of them will be enough. I'll be putting them closer to the floor by about 7' than the HPS fixtures are now. I search around to see if anyone I know has a light meter to see if I can take a before and after measurement.

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Custom Cabinets in Hartford County Connecticut

Leo G

Guess there's a good reason it wasn't answered in this thread. I asked it in another thread. Here was the chart they supplied online on the current draw on the fixture/ballast.

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Custom Cabinets in Hartford County Connecticut

K2

Maybe you could do a before and after photo of your shop with some colors in it. And post...

Bright hps's?? Makes be think of little green plants..

Leo G

Ya, those HPS's are bright. They are 22' up and I have 2 of them and they light the shop up pretty well. The color sucks. I dragged one of the fixtures up on a 12' step ladder up to about 14' off the floor and it was pretty bright on the floor. Not sure if the light spread is going to be enough at that height. I have 10' mounting cables and they can be adjusted shorter. So I will start at the low point and if the spread isn't enough I will move it up until it is, or until the brightness is diminished enough to stop. Remember, light intensity diminishes by the square of the distance it is moved. Holy crap, science came in handy LOL.

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Sawdust Follows Me Everywhere

http://lrgwood.com
Custom Cabinets in Hartford County Connecticut