Lighting HPS actual consumption vs. bulb rating

[Chanvremec]

I am wondering about the difference between the rated wattage of lights based on their bulbs vs. what the whole fixture actually consumes. For example, I was considering buying a HydroFarm Mini Surburst ( http://www.amazon.com/Hydrofarm-SBM150S-150-Watt-Mini-Sunburst/dp/B0055F80H0/ref=cm_cd_al_qh_dp_t ), which they list simply as a 150 watt fixture. However, if you read the reviews on Amazon, one person pointed out that this is only the wattage rating of the bulb and the fixture itself uses considerably more, which means it is not very efficient. According to him if it draws 150 watts the current draw should be 1.25 amps but he tested the unit and said that at startup it draws 4.5 amps and then lowers the draw to 3.2 amps. This would mean it is actually using more than 300 watts.

In other words, an efficient 250 watt lamp would probably be a better deal - it would be brighter and use about the same current.

Do all lights have this problem? Many of them are actually rated for the wattage they draw, which is what matters here, but the Mini Sunburst apparently is not.

Thanks!

 

[pop22]

I am wondering about the difference between the rated wattage of lights based on their bulbs vs. what the whole fixture actually consumes. For example, I was considering buying a HydroFarm Mini Surburst ( http://www.amazon.com/Hydrofarm-SBM150S-150-Watt-Mini-Sunburst/dp/B0055F80H0/ref=cm_cd_al_qh_dp_t ), which they list simply as a 150 watt fixture. However, if you read the reviews on Amazon, one person pointed out that this is only the wattage rating of the bulb and the fixture itself uses considerably more, which means it is not very efficient. According to him if it draws 150 watts the current draw should be 1.25 amps but he tested the unit and said that at startup it draws 4.5 amps and then lowers the draw to 3.2 amps. This would mean it is actually using more than 300 watts.

In other words, an efficient 250 watt lamp would probably be a better deal - it would be brighter and use about the same current.

Do all lights have this problem? Many of them are actually rated for the wattage they draw, which is what matters here, but the Mini Sunburst apparently is not.

Thanks!

Its my understanding that yes, MH/HPS lights are not very efficient especially the lower wattage unit ( those under 400 watts ) The most efficient are the 600 watt units. Ballasts on all units from 250 watts up consume about 100 to 140 watts. The old magnetic ballast are even bigger energy hogs, and considering they cost about the same as the digitals, I don't see why they even sell them anymore.

 

[GoeRilla]

I am wondering about the difference between the rated wattage of lights based on their bulbs vs. what the whole fixture actually consumes. For example, I was considering buying a HydroFarm Mini Surburst ( http://www.amazon.com/Hydrofarm-SBM150S-150-Watt-Mini-Sunburst/dp/B0055F80H0/ref=cm_cd_al_qh_dp_t ), which they list simply as a 150 watt fixture. However, if you read the reviews on Amazon, one person pointed out that this is only the wattage rating of the bulb and the fixture itself uses considerably more, which means it is not very efficient. According to him if it draws 150 watts the current draw should be 1.25 amps but he tested the unit and said that at startup it draws 4.5 amps and then lowers the draw to 3.2 amps. This would mean it is actually using more than 300 watts.

In other words, an efficient 250 watt lamp would probably be a better deal - it would be brighter and use about the same current.

Do all lights have this problem? Many of them are actually rated for the wattage they draw, which is what matters here, but the Mini Sunburst apparently is not.

Thanks!

No normally it´s not that bad.
My 400W magnetic draws about 450W, thats more normal and electronic ballasts waste even less.

Rilla.

 

[KsjAuto]

My 100w Old ballast draws 110w

 

[waah]

I'm not an expert on lights, but I got to say led lights are the only way to think.








I
have a couple, one is 136x3w, draws real 193w, and a mars 600w with veg or flower switch set. Just got it today. I just plugged it in and checked it out. No glass over the leds for max light, chrome reflectors, and a switch set that lets you optimize the light for whatever. I'm impressed as hell.
I don't know why I had this thought after turning it on and switching it back and forth. I took a quick peek at the bulbs in each mode,and I thought I should get another and put 1 on each side of my big chair. Maybe some Stevie ray sunglasses too. I could veg myself or go for bloom'. Anyone got ideas on nutes?
Cabin fever time around here, mid coast Maine.

 

[mephisto]

I did some tests the other day for my LED vs HPS SOG thread.

1) Phantom digital adjustable ballast, uses a microprocessor to dim the output, however consequently, whatever power setting you have it on.. It draws the same power.
60%
75%
100%
all pull 624w

2) Cheapo adjustable digital ballast - by CSL
50% - 380w
75% - 483w
100% - 630w
'SUPER' - 640w

3) Lumatek digital adjustable
400 - 410w
400w Super Lumens - 438w
600w - 630w
600w Super Lumens - 657w

I can't comment on smaller units as I have none to test.

Tried some newish magnetic ballasts, and they took an age to get up to full brightness/consumption. But I remember from measuring with our laser thermometer when they are up to temperature they are running 20-ish degrees hotter than the digital ballasts.
Could be some influence coming from the design of the casing, they are flat whereas the ridged design of the digitals will help dissapate some heat I'm sure.

 

[growbiewon]

I also noticed this about cfls too. a 55w cfl draws .8a @120 and a 23w cfl draws .38a @ 120. I had two of each bulb running a total of "156" watts but drawing 2.38a

 

[mauricem00]

I am wondering about the difference between the rated wattage of lights based on their bulbs vs. what the whole fixture actually consumes. For example, I was considering buying a HydroFarm Mini Surburst ( http://www.amazon.com/Hydrofarm-SBM150S-150-Watt-Mini-Sunburst/dp/B0055F80H0/ref=cm_cd_al_qh_dp_t ), which they list simply as a 150 watt fixture. However, if you read the reviews on Amazon, one person pointed out that this is only the wattage rating of the bulb and the fixture itself uses considerably more, which means it is not very efficient. According to him if it draws 150 watts the current draw should be 1.25 amps but he tested the unit and said that at startup it draws 4.5 amps and then lowers the draw to 3.2 amps. This would mean it is actually using more than 300 watts.

In other words, an efficient 250 watt lamp would probably be a better deal - it would be brighter and use about the same current.

Do all lights have this problem? Many of them are actually rated for the wattage they draw, which is what matters here, but the Mini Sunburst apparently is not.

Thanks!

magnetic ballast are a reactive load so will show a higher current draw but with this type of load the current and voltage are out of phase so you cant determine power draw by simply multiplying current bu voltage.the power meter on your house and a good commercial power meter measures actual power draw. a 150 watt hps with a magnetic ballast will draw about 180 watts and thats what a true power meter or the one on your house will show.many led light bulbs use the same kind of power supply and will show a high current draw but you need to factor in the phase shift between voltage and current to get the actual power draw. that 150 watt hps will give you 16000 lumens at about 180 watts actual draw. about 89 lumens per watt almost as good as a T5HO light for hps you need to use 250 watts to match the efficiency of T5s and over 400 watts with MH bulbs larger bulbs will give you greater efficiency but these are the points where HPS or MH start exceeding the efficiency of T5HO lights. hope this helps

 

[minime]

Lol I really need to get rid of my 150w hps,