Amperage question around 400W bulb with electronic ballast

THP · 08/12/2007, 01:44 PM

Bit of a stupid question here but when looking at the amperage requirements of some electronic ballasts for 400W bulbs, I noticed the operating current was 3.6 amps. With a 400W bulb on a 120v circuit that would be 3.33 so am I right that the ballast only uses 0.3 amps?

I'm trying to determine if a 3x400w MH system would run off a 15amp dedicated circuit and what the total draw from that circuit would be during"start-up"; when the lamps come on since apparently there is a larger capacity needed at that point.

THP · 08/14/2007, 06:07 AM

anyone?

stemonia · 08/14/2007, 07:34 AM

It should run. Your amperage is more like 3-4 amps per light/ballast combo. I would run them off a single circuit as long as i wasn't using it for anything else. The other thing I would do is put each ballast on a timer and stagger the startup so that they don't all come on at the same time. In the end you can get a amp meter to see the total draw from the lights and you might have some room to add another piece of equipment to that circuit.

THP · 08/14/2007, 07:39 AM

thanks very much for the reply. I am planning on staggering their startup as you suggest with timers.

der_wille_zur_macht · 08/14/2007, 08:19 AM

If you're REALLY curious about the current your given ballast/lamp combo will draw, Sanjay lists that info on his lighting test results:

http://www.reeflightinginfo.arvixe.com/

It's important to note that almost no "400w" MH lighting rigs actually draw 400w, and equally important that there are particular combinations that will draw ABOVE 400w, and others that will draw significantly BELOW 400w.

Of course, your circuit should have enough of a safety factor that these little 10 - 20% differences aren't important.

MalHavoc · 08/14/2007, 08:23 AM

I'm not an electrician, but it's generally recommended that you don't run a circuit close to it's maximum capacity for very long. I remember running a concrete saw with a 12A motor on a 15A circuit and the breaker kept tripping every ten minutes or so, and the wires and receptacle started to get warm. Ever unplug a kettle and find the power cord and plug warm to the touch? And that's usually just a few minutes!

If it was me, I'd put my lights on more than one branch just for peace of mind. If I trip a circuit, it'd be nice to not lose all of my lights at once.

THP · 08/14/2007, 08:40 AM

good point and this is exactly what my concern is. My only problem is I have only 2, 15 amp dedicated circuits to my tank. The other 15 amps was going to be for pumps and misc. items

MalHavoc · 08/14/2007, 09:20 AM

I suppose one possibility is to suggest 3x250w DE with really nice reflectors, instead of 3x400w. You'd lower your powerbill a bit, and that shouldn't be a problem for one 15A circuit.

THP · 08/14/2007, 09:23 AM

good point on 3 250 MH. That may be the way to go, at least from a circuit/power consumption perspective. Which is the limiting factor I might add

stemonia · 08/14/2007, 09:24 AM

How big is your tank and how much power (if you add up the listed amperage on the equipment) are you potentially going to draw. 30 amps is exactly what I have with a 150 gal reef. I'm running (2) 250W halides and 720 watts of VHO lighting. Not sure about the amperage on the VHO lighting but I am running them off (2) IceCap 660 ballasts. All lights are on one 15 amp circuit ( and have been for years without a fire) and everything else is on the other 15 amp circuit. My pumps draw a total of 6 amps and the rest of the equipment draws very little. I have lots of head room with 30 amps as far as I can tell. Of course, this is my setup. Just laying this out so you can make a comparison. I'm most certainly not an electrician either and don't want you to burn down your castle. When in doubt solicit the help of an expert. The cost of an electrician consultation is far less than the cost of the alternative... :-)

der_wille_zur_macht · 08/14/2007, 09:24 AM

What other equipment do you have? Unless you've got a ton of very powerful pumps or something, two 15a circuits should be more than enough - you just need to consider the load on each circuit.

Some people advise segregating equipment on circuits, i.e. all lighting on one circuit, all pumps on one circuit, etc. Personally, I like to split it up - put one light(s) and the closed loop pump (or powerheads) on one circuit, and the other light(s), return pump, and skimmer on the other line. That way, if either line goes down, you still have *some* light and *some* circulation.

stemonia · 08/14/2007, 09:32 AM

Agreed... the 250W halides are a great option and the trickle down effect on power consulption over the long term is a good thing. 400W halides generate more heat which means your chiller and A/C will run more often/longer. You can figure out the rest of the story... My 250's are driven by IceCap ballasts as well. Tank measurements are 60LX24WX24H and I have no issues with lighting or lack thereof.

THP · 08/14/2007, 09:36 AM

The tank is a 180 gallon with a 60 gallon sump. I have a dart closed loop on a 4 way oceans motions. It is plumbed with 2 returns through each side of the tank. The main pump is a blue line. (I forget the amperage draw on these pumps...key thing to know, I know, I'll check again when I get home) but the total circulation with head loss is over 3400 gallons per hr. I then have a MarineTech skimmer which runs with 2 Sedra pumps and 2, 300W heaters.

The intention of the tank is for SPS only.

THP · 08/14/2007, 09:38 AM

Oh, one other point on the 180 gallon is size...its a standard, 6 foot by 24" x 24"

stemonia · 08/14/2007, 09:41 AM

I'd be willing to bet (based on experience) that the 250W halides will work perfectly for you. The only dimensional differnce between our tanks is 12 inches of length. I LOVE SPS as well and mine are all growing just fine with 250's. I would agree that three halides on your tank would be better than two.

der_wille_zur_macht · 08/14/2007, 09:50 AM

IME 24" is pushing it for 250's if you want to be able to keep any SPS anywhere in the tank. At the very least, you'll have to stick with the higher output bulbs (most of which are 10kk or so), and as such your bulb choice will be limited.

250's will certainly cut it, but will also be somewhat limiting if you want the absolute best growth, best colors, and no bulb choice restrictions.

MalHavoc · 08/14/2007, 09:52 AM

If it matters, JBNY's tank, which was one of the nicest SPS tanks I've ever seen, was lit with 3x250w MH and 2x140w VHO.

http://www.reefkeeping.com/issues/20...totm/index.php

He won Tank of the Month with that setup.

der_wille_zur_macht · 08/14/2007, 09:59 AM

I want to make it clear that I'm not knocking the 250w option, just providing a point of view that's based on having had both over 24" and taller (26") tanks.

THP · 08/14/2007, 10:09 AM

There is no doubt that JBNY's tank is very nice however, it seems to be missing that brightness that 400s have. However I do realize that the choice of bulbs and ballast can certainly have a different effect regardless of wattage....I guess thats whats making lighting choice so difficult.

THP · 08/14/2007, 10:10 AM

"I want to make it clear that I'm not knocking the 250w option, just providing a point of view that's based on having had both over 24" and taller (26") tanks."

so in your opinion, 400w would be the smarter choice then?

der_wille_zur_macht · 08/14/2007, 10:11 AM

If it were my tank, and I wanted to stuff it with SPS, I would undoubtedly use 400w. Especially since your listed location is the "Great White North." Up here cooling doesn't seem to be much of a problem.

stemonia · 08/14/2007, 10:14 AM

I don't think the 400's are necessary but that's just my opinion. My 250's are very bright and I can't say that i have any issues or complaints. I'm happy I went that way for many reasons. Making a lighting decision is no coin toss by any means.

stemonia · 08/14/2007, 10:16 AM

Ah ha! I did't notice that "Great White North" label. That could have a bearing on my decision as well. I live in the VERY HOT South so making a lighting decision is always impacted by the fact that the temp is in the 90's for almost 7 months out of the year.

THP · 08/14/2007, 11:02 AM

Well then, what do ya know!!! living in the great white north may have an advantage...never thought I'd say that cause I hate snow!

So, from all these posts (and I thank you all very much) I think 400s are the best way to go which by the sounds of it, they would give me the most choice in bulbs without having to worry about PAR as much as I would with 250s. Now my only limiting factor will be the available amperage. Aye! the obstacles we must overcome.

stemonia · 08/14/2007, 11:34 AM

LOL... Back to the original issue at hand I guess! :-) Good luck with the decision. I'll be enjoying our 100 degree day while you contemplate the onset of winter in the next month or so.

08/12/2007, 01:44 PM	#1
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	Amperage question around 400W bulb with electronic ballast Bit of a stupid question here but when looking at the amperage requirements of some electronic ballasts for 400W bulbs, I noticed the operating current was 3.6 amps. With a 400W bulb on a 120v circuit that would be 3.33 so am I right that the ballast only uses 0.3 amps? I'm trying to determine if a 3x400w MH system would run off a 15amp dedicated circuit and what the total draw from that circuit would be during"start-up"; when the lamps come on since apparently there is a larger capacity needed at that point. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 06:07 AM	#2
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	anyone? __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 07:34 AM	#3
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	It should run. Your amperage is more like 3-4 amps per light/ballast combo. I would run them off a single circuit as long as i wasn't using it for anything else. The other thing I would do is put each ballast on a timer and stagger the startup so that they don't all come on at the same time. In the end you can get a amp meter to see the total draw from the lights and you might have some room to add another piece of equipment to that circuit. __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show

08/14/2007, 07:39 AM	#4
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	thanks very much for the reply. I am planning on staggering their startup as you suggest with timers. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 08:19 AM	#5
der_wille_zur_macht Team RC Member Join Date: Sep 2003 Location: NY Posts: 17,749	If you're REALLY curious about the current your given ballast/lamp combo will draw, Sanjay lists that info on his lighting test results: http://www.reeflightinginfo.arvixe.com/ It's important to note that almost no "400w" MH lighting rigs actually draw 400w, and equally important that there are particular combinations that will draw ABOVE 400w, and others that will draw significantly BELOW 400w. Of course, your circuit should have enough of a safety factor that these little 10 - 20% differences aren't important. __________________ Inconveniencing marine life since 1992 "It is my personal belief that reef aquaria should be thriving communities of biodiversity, representative of their wild counterparts, and not merely collections of pretty specimens growing on tidy clean rock shelves covered in purple coralline algae." (Eric Borneman)

08/14/2007, 08:23 AM	#6
MalHavoc Infinitely Prolonged Join Date: Apr 2002 Location: Canada Posts: 10,850	I'm not an electrician, but it's generally recommended that you don't run a circuit close to it's maximum capacity for very long. I remember running a concrete saw with a 12A motor on a 15A circuit and the breaker kept tripping every ten minutes or so, and the wires and receptacle started to get warm. Ever unplug a kettle and find the power cord and plug warm to the touch? And that's usually just a few minutes! If it was me, I'd put my lights on more than one branch just for peace of mind. If I trip a circuit, it'd be nice to not lose all of my lights at once. __________________ Jason "Empathy, he once had decided, must be limited to herbivores or anyhow omnivores who could depart from a meat diet. Because, ultimately, the empathic gift blurred the boundaries between hunter and victim, between the successful and the defeated." -- Do Androids Dream of Electric Sheep?, Philip K Dick

08/14/2007, 08:40 AM	#7
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	good point and this is exactly what my concern is. My only problem is I have only 2, 15 amp dedicated circuits to my tank. The other 15 amps was going to be for pumps and misc. items __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 09:20 AM	#8
MalHavoc Infinitely Prolonged Join Date: Apr 2002 Location: Canada Posts: 10,850	I suppose one possibility is to suggest 3x250w DE with really nice reflectors, instead of 3x400w. You'd lower your powerbill a bit, and that shouldn't be a problem for one 15A circuit. __________________ Jason "Empathy, he once had decided, must be limited to herbivores or anyhow omnivores who could depart from a meat diet. Because, ultimately, the empathic gift blurred the boundaries between hunter and victim, between the successful and the defeated." -- Do Androids Dream of Electric Sheep?, Philip K Dick

08/14/2007, 09:23 AM	#9
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	good point on 3 250 MH. That may be the way to go, at least from a circuit/power consumption perspective. Which is the limiting factor I might add __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 09:24 AM	#10
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	How big is your tank and how much power (if you add up the listed amperage on the equipment) are you potentially going to draw. 30 amps is exactly what I have with a 150 gal reef. I'm running (2) 250W halides and 720 watts of VHO lighting. Not sure about the amperage on the VHO lighting but I am running them off (2) IceCap 660 ballasts. All lights are on one 15 amp circuit ( and have been for years without a fire) and everything else is on the other 15 amp circuit. My pumps draw a total of 6 amps and the rest of the equipment draws very little. I have lots of head room with 30 amps as far as I can tell. Of course, this is my setup. Just laying this out so you can make a comparison. I'm most certainly not an electrician either and don't want you to burn down your castle. When in doubt solicit the help of an expert. The cost of an electrician consultation is far less than the cost of the alternative... :-) __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show

08/14/2007, 09:32 AM	#12
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	Agreed... the 250W halides are a great option and the trickle down effect on power consulption over the long term is a good thing. 400W halides generate more heat which means your chiller and A/C will run more often/longer. You can figure out the rest of the story... My 250's are driven by IceCap ballasts as well. Tank measurements are 60LX24WX24H and I have no issues with lighting or lack thereof. __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show

08/14/2007, 09:36 AM	#13
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	The tank is a 180 gallon with a 60 gallon sump. I have a dart closed loop on a 4 way oceans motions. It is plumbed with 2 returns through each side of the tank. The main pump is a blue line. (I forget the amperage draw on these pumps...key thing to know, I know, I'll check again when I get home) but the total circulation with head loss is over 3400 gallons per hr. I then have a MarineTech skimmer which runs with 2 Sedra pumps and 2, 300W heaters. The intention of the tank is for SPS only. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 09:38 AM	#14
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	Oh, one other point on the 180 gallon is size...its a standard, 6 foot by 24" x 24" __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 09:41 AM	#15
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	I'd be willing to bet (based on experience) that the 250W halides will work perfectly for you. The only dimensional differnce between our tanks is 12 inches of length. I LOVE SPS as well and mine are all growing just fine with 250's. I would agree that three halides on your tank would be better than two. __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show

08/14/2007, 09:50 AM	#16
der_wille_zur_macht Team RC Member Join Date: Sep 2003 Location: NY Posts: 17,749	IME 24" is pushing it for 250's if you want to be able to keep any SPS anywhere in the tank. At the very least, you'll have to stick with the higher output bulbs (most of which are 10kk or so), and as such your bulb choice will be limited. 250's will certainly cut it, but will also be somewhat limiting if you want the absolute best growth, best colors, and no bulb choice restrictions. __________________ Inconveniencing marine life since 1992 "It is my personal belief that reef aquaria should be thriving communities of biodiversity, representative of their wild counterparts, and not merely collections of pretty specimens growing on tidy clean rock shelves covered in purple coralline algae." (Eric Borneman)

08/14/2007, 09:52 AM	#17
MalHavoc Infinitely Prolonged Join Date: Apr 2002 Location: Canada Posts: 10,850	If it matters, JBNY's tank, which was one of the nicest SPS tanks I've ever seen, was lit with 3x250w MH and 2x140w VHO. http://www.reefkeeping.com/issues/20...totm/index.php He won Tank of the Month with that setup. __________________ Jason "Empathy, he once had decided, must be limited to herbivores or anyhow omnivores who could depart from a meat diet. Because, ultimately, the empathic gift blurred the boundaries between hunter and victim, between the successful and the defeated." -- Do Androids Dream of Electric Sheep?, Philip K Dick

08/14/2007, 09:59 AM	#18
der_wille_zur_macht Team RC Member Join Date: Sep 2003 Location: NY Posts: 17,749	I want to make it clear that I'm not knocking the 250w option, just providing a point of view that's based on having had both over 24" and taller (26") tanks. __________________ Inconveniencing marine life since 1992 "It is my personal belief that reef aquaria should be thriving communities of biodiversity, representative of their wild counterparts, and not merely collections of pretty specimens growing on tidy clean rock shelves covered in purple coralline algae." (Eric Borneman)

08/14/2007, 10:09 AM	#19
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	There is no doubt that JBNY's tank is very nice however, it seems to be missing that brightness that 400s have. However I do realize that the choice of bulbs and ballast can certainly have a different effect regardless of wattage....I guess thats whats making lighting choice so difficult. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 10:10 AM	#20
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	"I want to make it clear that I'm not knocking the 250w option, just providing a point of view that's based on having had both over 24" and taller (26") tanks." so in your opinion, 400w would be the smarter choice then? __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 10:11 AM	#21
der_wille_zur_macht Team RC Member Join Date: Sep 2003 Location: NY Posts: 17,749	If it were my tank, and I wanted to stuff it with SPS, I would undoubtedly use 400w. Especially since your listed location is the "Great White North." Up here cooling doesn't seem to be much of a problem. __________________ Inconveniencing marine life since 1992 "It is my personal belief that reef aquaria should be thriving communities of biodiversity, representative of their wild counterparts, and not merely collections of pretty specimens growing on tidy clean rock shelves covered in purple coralline algae." (Eric Borneman)

08/14/2007, 10:14 AM	#22
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	I don't think the 400's are necessary but that's just my opinion. My 250's are very bright and I can't say that i have any issues or complaints. I'm happy I went that way for many reasons. Making a lighting decision is no coin toss by any means. __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show

08/14/2007, 10:16 AM	#23
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	Ah ha! I did't notice that "Great White North" label. That could have a bearing on my decision as well. I live in the VERY HOT South so making a lighting decision is always impacted by the fact that the temp is in the 90's for almost 7 months out of the year. __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show

08/14/2007, 11:02 AM	#24
THP Registered Member Join Date: May 2003 Location: Great White North Posts: 452	Well then, what do ya know!!! living in the great white north may have an advantage...never thought I'd say that cause I hate snow! So, from all these posts (and I thank you all very much) I think 400s are the best way to go which by the sounds of it, they would give me the most choice in bulbs without having to worry about PAR as much as I would with 250s. Now my only limiting factor will be the available amperage. Aye! the obstacles we must overcome. __________________ pickled radishes flourish in the clear moon light Current Tank Info: 180g AG, OM4 way CL on Dart pump, BlueLine main, 50-60g sump, MT skimmer w/2 Sedra circulation pumps, 3x400w 12k Reeflux bulbs/CoralVue elec. ballasts in Luminarc III reflectors.

08/14/2007, 11:34 AM	#25
stemonia Premium Member Join Date: May 2003 Location: Covington, LA Posts: 86	LOL... Back to the original issue at hand I guess! :-) Good luck with the decision. I'll be enjoying our 100 degree day while you contemplate the onset of winter in the next month or so. __________________ If it weren't for electricity, we'd all be watching TV by candlelight. Current Tank Info: 120 Show