Can you run a 1k lamp and a 400 on one circuit safely?

[DELTA9]

Hi grasscity nice forums! My question is Can you run a 1k lamp and a 400 on one circuit safely?

[tenacity2986]

Yes, you can but make sure that your circuit is rated for minimally 20 amps. This is a bare minimum. You may want to stagger the lights by 5 minutes of turning on so you dont blow the fuse since lamps typically take more power to start up.

[Francious70]

Figure 1400 watts with 120 volts. Those lights pull 11.6 amps if they're 100% efficient, but I'd say they're more like 50% efficient. Max, so figure 23 amps constant draw. Unless the breaker for that circuit is rated at 25 amps and there's nothing else on the circuit, then no, you can't run them both on the same circuit.

[montdj]

A 1000 watt lamp pulls about 9.5 amps of power. I doesnt matter how efficient the lamp is.(Thats just how well it uses the electricty) If a lamp is only 50% efficient that just means its only using 50% of the power and the other 50% is wasted. Most hid lamps or way more efficient then that. I beleve that most sunsystem ballast are about 75-85% and the new electronic ones are 99%. But to answer your question and 1000 and a 400 would pull allmost 15 amps. That would be fine if you have a 20 amp circuit. If its a 15 you would be asking for trouble. See you should never go over 75% of the circuit rating ie on a 20 amp circuit never run more than 15 amps. I hope that answered you question. If you need help trying to figure out how big the circuit is let me know.


Montdj

[montdj]

Oh and by the way a 1000 watt lamp uses about 1100 watts and a 400 uses about 460 so the 2 use about 1560 watts of electricty per hour or 1.56 kw/hr If you know how much the electric company charges per kw/hr you can figure out how much its going to cost you each month.

[tenacity2986]

Yea but the initial startup of lamps may draw more current than they need at equilibrium. So a 1000 watt lamp could be using 1300 watts to startup but 1nce ignited, it will stay around 100o watts. This is why i say that it wouldnt be a bad idea to stagger them, that way, if ur not around and the circuit blows when the lights turn on, ur plants dont get confused from no lighting. If you have a 25 amp circuit, i would have NO concern. but with a 20, u have a marginal amount to worry about so stagger them if its 20.

[montdj]

Watts and amps dont work like that. You could have a bigger draw at start up but in amps not watts. Having them start up five minutes apart is a good idea. Its not needed on a 20 amp circuit but is not a bad idea. I dont care if you just turned on the light or not its going to use 1100 watts of power to run it. Just remember to not go over 75% of the circiuts rated amps and you should be fine.

[tenacity2986]

actually montj, watts and amps directly correlate to eachother.

Watts are the units for power . Power = current(amps) X Voltage(volts)

So if you increase amps, and the voltage remains the same(120v), u will absorb a positive power.

[montdj]

Ok so you know ohms law. All im trying to say is that at start up its not the wattage you should be worried about it the amps. Im not trying to affend any one. And your right (amps x voltage = watts). What i was trying to say i think came out wrong.
I was just trying to say if hes running a 1000 and a 400 on a 20 amp circuit and thats it hes fine stagering them or not.

[tenacity2986]

lol, no big deal. just making sure the right info gets out to people.(delta9)