How many total watts can I run through a 200 amp panel? 24,000 or 48,000?

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AllDay

AllDay

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I assumed the reason we run our lights using 220 power is so we can get more amps out of our main panel. Is this assumption correct? Any electricians care to chime in?
 
Cherrorist

Cherrorist

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Power(watts) = current(amps) x voltage so at 220 volts you'd get roughly 44kw or 44,000w this doesn't take into account power factor but I wouldn't worry too much about that.
I'm in England so the lowest incoming voltage we have is 230v but your right that if you had lower voltage the current would be higher but obviously the watts is still the same.
 
Natural

Natural

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I assumed the reason we run our lights using 220 power is so we can get more amps out of our main panel. Is this assumption correct? Any electricians care to chime in?

no..it's just more efficient.
A digital ballast will use approx 5 amps @ 220v and approx 10 amps @ 120v..to give you a frame of reference. Always use the 80% usage rule of any circuit or panel. Assuming that the draw from the panel is directly wired to a meter/pole and absolutely nothing else is drawing power from it..you would have approx 160 amps to work with. One must take into account start-up draws, which are usually much higher than what the appliance is rated for..especially magnetic ballasts and air conditioners. Read mfg specs or research the net for max possible amperage draw upon start-up.
 
AllDay

AllDay

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no..it's just more efficient.
A digital ballast will use approx 5 amps @ 220v and approx 10 amps @ 120v..to give you a frame of reference. Always use the 80% usage rule of any circuit or panel. Assuming that the draw from the panel is directly wired to a meter/pole and absolutely nothing else is drawing power from it..you would have approx 160 amps to work with. One must take into account start-up draws, which are usually much higher than what the appliance is rated for..especially magnetic ballasts and air conditioners. Read mfg specs or research the net for max possible amperage draw upon start-up.

So can I run twice as many watts through a main panel using 220 as opposed to 110? Or is the total wattage fixed? Cherrorist seems to believe that twice as many watts can be pulled through a main panel using 220 power.
 
Natural

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Like Cherrorist has eluded to..learn Ohm's law. The part that helps the most is watts= volts x amps
Adding watts will get you into trouble sometimes...like a 1k ballast uses a bit more than 1k of power to light the bulb.
 
Natural

Natural

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This might help help you better understand. http://www.hamuniverse.com/ohmslaw.html

Or even simpler..like this:

voltage is 120 or 240...240 is bigger wire..so you can allow the same amount of juice with less resistance (heat). Generally speaking, the biggest resistance is your appliance.
It is a lot like plumbing to an extent. Your panel is your water tank...you will never exceed that limit...whether your pipes (wires) are bigger or smaller. capiche?
 
AllDay

AllDay

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So what you're saying here is that even if I were to run all my appliances on 220 I'd only be able to get 16000 watts out of a 200 amp panel, correct? Which means that using 220 power does not allow me to get more wattage out of my main panel, correct?
 
Natural

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Gotta correct myself...lol. Ballasts run closer to 2.75 amps @220v and more like 5.5 amps @ 120v. So forget those numbers I was just giving reference.
So in reality..you can run 27 lights if you have full usage of the panel..dedicated to lights only.
I think where you're getting confused is the difference of how we get 220v and 120v. The power coming into the panel is 2 hot legs each carrying 120v...so you can think of your panel as being 240v power source. When we use one of those legs of power with a neutral wire we get 120v. The neutral doesn't provide power..it helps the one leg of 120v alternate polarities..which is the def of alternating current.
Essentially when we split the power into 120v we are basically "using smaller pipes" to run our juice along. So we always start @ 220v at the panel...from there we break it down into how we use it...different size wires/circuits.
Sorry about the numbers thing...just smokin and explaining too fast...if you need more help with adding loads...let me know.
 
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Myco

Myco

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I think there is some confusion going on in this thread.

By running 240v as opposed to 120v you ARE allowed to run more lights off of a given circuit/panel.

Amps = Watts/volts

Watts do not change, voltage and amperage does. The amount of amperage is what dictates how much power can run through said panel.

Running a single 1k at 120v, pulls 8.6 amps. 1000/120 = 8.6 amps.

Running a single 1k at 240v, pulls 4.3 amps. 1000/240 = 4.3

So with a 200 amp panel, assuming nothing but lights are going to be on said panel, it is recommended to not exceed 80% of circuit capacity. So we're working with 160 amps. If we divide 160 (total amps available) by 4.3 (a single 1k at 240v) we get 37.21. So basically, 36 or 37 lights. If we were to run the same lights on 120v, we'd divide 160 by 8.6, as running at half the voltage, we will double the amperage... this works out to 19.28 lights... so 18 or 19 lights.

It is an obvious choice when it comes to running lights on 120v vs. 240v when running more that 1k or 2k... and even then, it allows you to have more wattage on a specific circuit. Smaller circuit size, which means smaller wire. It allows you to more efficiently wire your setup, it doesn't affect the actual efficiency of the lights or power consumption.

Hope that all makes sense, good luck, and be safe!


Source: I am an HVAC professional/licensed electrician.

Edit: voltage varies up to 250v depending on specific area, always calculate by 240v, because the lower the voltage, the higher the amperage. When considering larger loads, this does make a difference, and you want to stay within 80% of maxing a circuit with a full, constant load.
 
AllDay

AllDay

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Thanks to everyone for the answers! I've heard conflicting answers to this question. Has anyone actually seen a flower room with 16,000 watts worth of lighting running at the same time (not 2-8,000 watt rooms running on a flip) on a 200 amp panel?
 
Myco

Myco

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Why Capulator? And for sake of example, the math works out to 36. Not saying the wiring, and wire distances might not get out of wack with 36, but let's say your 20.

Let's assume the 200 amp service is dedicated to lighting, and another 200 amp service is in place for other components.

A large electric furnace in a home uses 25kw. A water heater 5kw, then take into account a dryer, and an oven. We can now be somewhere around that 36kw. How is this able to be jammed into a 200 amp service, not to mention all of the other lighting, appliances, outlets, etc, if 20kw in HID couldn't be? Of course it's not a power issue...

It comes down to how the system is wired, subpanels, and the actual lights daisy chained with terminal blocks, heavy duty contactors for switching.
 
Myco

Myco

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Thanks to everyone for the answers! I've heard conflicting answers to this question. Has anyone actually seen a flower room with 16,000 watts worth of lighting running at the same time (not 2-8,000 watt rooms running on a flip) on a 200 amp panel?
It's not a matter of opinion, it's science! Haha... more volts, lower amps. Running your lights at 240v allows more lights to be ran on a given circuit.

And yes. Just a couple of months ago I installed a few mini splits at a double level site, with a 200amp service upper level, 200amp service lower level, and helped him fine tune some wiring issues. There was 15kw on each level... And FTR this was through a licensed contractor, with permits pulled, and inspected by a state inspector.
 
AllDay

AllDay

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I understand that by running my lights at 240v I'm able to run more lights on a given circuit. But does the same apply to the main panel?
 
Natural

Natural

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Thanks to everyone for the answers! I've heard conflicting answers to this question. Has anyone actually seen a flower room with 16,000 watts worth of lighting running at the same time (not 2-8,000 watt rooms running on a flip) on a 200 amp panel?

You need to consider things in actual amperage instead of watts...lol. You will be mislead. Add up all your total amps...for each device. Read the actual appliance labels. You can devote a certain portion of your amps for lights..like a 30 40 or 60 amp 2 pole 220v circuit. Then divide the rest of your amps for your AC...then all the 120v stuff on the rest. If you use the 80% rule for each circuit..you can max the panel to add all the circuits up to 200 amps...because you've already considered the 80% rule for each circuit.
How many lights do you want to run? The panel should be divided into circuits.
 
Myco

Myco

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I understand that by running my lights at 240v I'm able to run more lights on a given circuit. But does the same apply to the main panel?
Yes!

Think of a panel as a 200 amp circuit, when I refer to a circuit I was using it as a for-example sort of thing.

And also for the record, the panel would obviously be divided into separate sub panels/circuits.
 
Myco

Myco

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And for the record brother, if this is not a separate panel to dedicate to a grow space, you need to consider the entire load of your home, and that is a whole different ballgame. All of the examples I spoke of, I was referring to a panel that would be dedicated to lighting. With 16kw you could dedicate a 200amp service to a grow and still have room for other components of the grow, but if this is the same 200 amp panel as your living space, then a calculation with COMPLETELY different factors will come into play. It depends exactly what you're trying to do here boss.
 
Natural

Natural

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And for the record brother, if this is not a separate panel to dedicate to a grow space, you need to consider the entire load of your home, and that is a whole different ballgame. All of the examples I spoke of, I was referring to a panel that would be dedicated to lighting. With 16kw you could dedicate a 200amp service to a grow and still have room for other components of the grow, but if this is the same 200 amp panel as your living space, then a calculation with COMPLETELY different factors will come into play. It depends exactly what you're trying to do here boss.

Good explanations..you should be a teacher!

Anybody want one of these
All ya need is a 240v disconnect to your panel with a 150 amp double pole breaker and you're in business. Fuck, I wish.
 
Capulator

Capulator

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My AC alone pulls 45 amps on start up and it is a portable 5 ton unit that barely keeps up with 9k in the summer. Each 1k light is 4.5 amps running on 240. A dehuey is 8 amps. I haev 2 of those to keep up. Most residential dehueys are 110. You should leave 10-20% free on your breakers at all times, includign your main breaker so forget about 200 amps start thinking 180 amps.

With 40 lights you are gonna need 15-20 tons of cooling. There is no fuckin way you can put all that on a 200 amp service. Sorry.
 

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