Power consumption

cat of curiosity said:

half the amps, twice the voltage is technically correct, although 240v is slightly more efficient than 120v. it can save you a dollar or few a month. the reason for that is the OPPOSITE of what you just said. higher voltage means LARGER wire, which means less impedance/resistance. a 240v recep is wired with no less that 12/2 wire, where as your 120v/15-20a breakers run on 14/2.

12/2 has half the resistance of 14/2, and so 240v is more efficient (though not by twice, separate issue).

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Higher voltage means less amps which means thinner wire. You're not an electrician, are you?

ttystikk said:

Higher voltage means less amps which means thinner wire. You're not an electrician, are you?

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higher voltage means larger wire. i AM an electrician.

ttystikk said:

Higher voltage means less amps which means thinner wire.

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no, it doesn't. lower amps at higher voltage means you can use more voltage in a house. this is why your dryer runs on 30a instead of 60a with only a 200a supply.

more voltagexamps means larger wire. ohm's law bubba...

20ax120v = 2400w available to that circuit
30ax240w = 7200w available to that circuit

please explain how to transfer more heat (watts) through smaller wire?

cat of curiosity said:

20ax120v = 2400w available to that circuit
30ax240w = 7200w available to that circuit

please explain how to transfer more heat (watts) through smaller wire?

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Because you'd need thicker wire to carry the same load at half the volts.

ttystikk said:

Because you'd need thicker wire to carry the same load at half the volts.

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ok, so lets go with this. lets say you have a 1kw hps. you use a 20a 120v circuit. that'll work, and you'll have 1400w still availvable.

if you use a 10a 240v circuit, you can use the same wire, and still be able to run an additional 1400w.

however, if you double or triple the current, you need to use a larger wire to prevent a fire. watts = lost energy = heat.

so, a 20a 120v circuit will run on a 14/2 gauge wire.

a 20a 240v circuit will need TWICE the wire as it is supplying twice the power. (10/3 for a dryer at 30a, and that's code) even your electric range runs off 10/2, as does your electric water heater. big power, big wire....

it's not rocket surgery

i'm not picking on you, a lot of people have a hard time comprehending this in college. i'm an electrician, and i am NOT lying to you.

axv=w

And this is why I HIRE an electrician to rewire my breaker box. I tell him/her how many kilowatts I'm planning on running in a particular space and he tells me when I can do it. TA DA problem solved

Friction1957 said:

And this is why I HIRE an electrician to rewire my breaker box. I tell him/her how many kilowatts I'm planning on running in a particular space and he tells me when I can do it. TA DA problem solved

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i've helped people double-use a dryer circuit to power lights. twice the voltage means it uses half the amps, which means more lights on that circuit. just don't try to run the dryer when the lights are on, you will trip the circuit.

those cases were rentals, and they did not want to add a sub-panel (landlord and permit issues)

cat of curiosity said:

those cases were rentals, and they did not want to add a sub-panel (landlord and permit issues)

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yea that would make a difference. I'm doing outdoor until later this fall. Our box is already pretty max out, I'm going to have him do a new box and put in the necessary updates to pull off the two different grow rooms we'll be using. I'm even thinking of having it on a separate meter, makes for easier tax deductions come tax time. Being legal and owning the space can make a huge difference in the choices you make.

I just run a 600watt hps and 6" ruck inline, they are quite low amps, probably less than 3amps in total, house fuses handle that with ease luckily.