electric plan...please disect

[inreplyavalon]

Here is my situation. Hope someone is gentle enough to help. I have had success doing my own wiring so far, but as safety is of the utmost importance i have a few questions.

I have TWO 30A 240 lines running into my space. one is going to have an intermatik timer switch with 8 outlets for my lights. I am running 5400 watts. 4x600 and 3x1000. If my math is correct that will draw 22.5 Amps of power. So one of my 30 amp 240 lines will do the job for the lights, i think? How do i know if its 220 or 240?

For my other 30amp 240 line i will be plugging in an AC. Here is my dillema. I also want to run some 120v peripherals off this 240 line. Is this possible?
Thanks for sharing all of you with a bit more sparky in ya.

 

[cyberwax]

Yes your math is somewhat correct, but the voltage your getting is probably around 230v, so (Amps = Watts/Volts) 5400 / 230 = 23.47 amps, tho you have to calculate in 20% more amps used on startup of ballasts, this could be worked around tho by not starting all lights at once, however your cutting it mighty close. I wouldnt run this system myself to be honest. How big is ur ac and does it really need all that power for itself, cant you run one or two ballasts on that circuit?

About running 120v peripherals of the 240v(230v) line; i actually have no experience, but im sure someone will dial in soon enough to help you out. However technically it shouldnt be a problem, just be careful!

 

[inreplyavalon]

cyberwax thanks for checking this thread out.

So by my math with the 20% buffer for surges i would be at 28 and some change amps. This is not considered safe in your eyes? I thought the 20% was the buffer to insure safety? I admit i don't understand it all well, just know what i have read.

The AC i will be using will need 13 amps. So i could run lights on that, i just don't know how to have some of the switches on my intermatik timer nad some of them(the ac) not. In other words i want to have the AC independent of my light timer so it is always on.

I don't know much but i am extra cautious when doing electric and i appreciate you helping out.

 

[Lakota412]

If your worried about amperage draw on the lighting system, remove one 1000w from the system.

Take the other 220v 30 amp line and install a Square D 6/12 sub panel. Re-feed the timer with a 220v 20 amp breaker (#12/2 NM-B romex, with ground) to re-feed the 1000w light removed from the other 220v lighting system.

Install the outlet for your A/C and feed it as well out of the Square D sub panel.

You need a neutral to add any 120v outlets off of the 220v circuits. You could cheat and add a #10 THHN wire from the sub panel to the panel the 220v circuits come from. with enough tape you can make it look ok too. This is against code, but will work. It's not unsafe, as long as the #10 THHN wire is well protected.

I am assuming the existing 30 amp 220v circuits are a 3 wire system, (2 insulated and 1 un insulated wire...in the cable)

Maybe you got lucky and they are 4 wire circuits. (1-black 1-red 1 white 1 bare copper)

If so then you are set.

 

[inreplyavalon]

Lakota much respect for sharing your expertise. I had to read your post 6-7 times to understand what your saying, but i finally get it. Or at least i think i do understand some of it.

I believe that one of my 30 amp wires has 4 wires in it. It used to be for a hot tub(i'm guessing) and since i only have experience with 10/2 i was wondering what i would do with the other extra wire. So basically to wire in a 120 outlet i would use one hot one neutral and the ground? Is the neutral essentially an unpowered line, and the red and black each run 120 V a piece? I know these may seem like silly questions but i would love to understand what i am doing.

 

[inreplyavalon]

oh yeah whats 6/12 mean for the sub panel?

 

[Bunz]

oh yeah whats 6/12 mean for the sub panel?

It'll hold 6 DP or 12 SP breakers..............

 

[whatissixbynine]

.

 

[inreplyavalon]

So i just discovered that the wires i am going to be using for this project are ?/3. Not sure if they are 10/3 or 8/3. My question is that the wires have a red, black, white, and ground. How do i attach a 10/2 to this 10/3? Do i just leave out the white neutral?

 

[inreplyavalon]

I give myself one bump a year...ready set go

 

[Lakota412]

sorry I was away, but back to answer some questions.

If the wires are _/3 (#8 or #10) this means there is a insulated white wire included. This is your neutral. It should hook up in the panel on the neutral bar, not on a circuit breaker. The black and red should be attached to breakers. The bare copper to a ground bar.

you need to properly terminate these wires to utilize them in what you want.

The "sub" panel would have a neutral bar inside of it. The white wire in the _/3 would hook to this. The sub Panel should have a ground bar also. It usually attaches to the back of the panel, directly to the metal of the breaker box. This is where the bare copper ground wire attaches. The black and red wires would attach/terminate to 2 different lugs in the sub panel. Then when you install your 120v circuits, all you need to do is attach the white of the 120v circuit to the neutral bar in the sub panel, the color wire attaches to the breaker, and bare copper to the ground bar in the sub panel.

Hope this helps, I'll check back soon, sorry for the delay.

Happy New year

 

[Lakota412]

if you wanna attach the 10/2 to the 10/3 black to black-white to red- bare copper to bare copper.

I am assuming the bare copper is going to used as a ground only, and not as a neutral in a 120v circuit.

If your thinking of the 10/2 to 10/3 to get 120v circuits out of it, then Black to black- white to white- and bare copper to bare copper.

put it in a junction box, use lineman pliers to twist the wires together. Don't rely on the wire nuts to do this. Get the right sized wire nuts and use them.

 

[inreplyavalon]

hah thanks for checking back lakota. I think i am going to keep the AC on the same timer as the lights for now and that way i ca avoid installing the sub panel.
question about this install.
"if you wanna attach the 10/2 to the 10/3 black to black-white to red- bare copper to bare copper."
What do i do with the extra Red on the 10/3 when making this attachment? i want to keep the outlet 240v so i was thinking i would not be using the white wire in the 10/3, no?
thanks

 

[Lakota412]

If your trying to get a 120v circuit from the 10/3 using a 10/2 to feed the 120v circuit then you would have the red wire from the 10/3 left over.

The 10/3 should be 120v from the black and also from the red. Each when touched with a tester...(black to white or the ground wire), should read 120v....(red to white or the ground wire) should also read 120v....black to red you should red 220v between them....

So if you use a 120v circuit from the 10/3 you will have an extra color wire left over. The color wires should be the energized ones.

Use either the black OR red with the white to get your 120v circuit.

 

[inreplyavalon]

I don't mean to be so darn confusing...

I am no longer trying to get a 120v circuit. all i really want to do is extend my dryer outlet which is 10/3 using a 10/2 wire. I want the final outlet at the end of the line to remain 240v.

So when connecting my 10/3 dryer wires to the extension wire which is 10/2 which of the 10/3 wires will not be used? I am assuming the neutral but what do i do with it? Just put a wire nut on the end and forget about it?

Thanks for continuing to help...

 

[grow nerd]

Just install a subpanel at the other end like everyone suggested.

 

[inreplyavalon]

grownerd it was suggested that i install a sub panel when i wanted to get some 120v out of my 240v circuit. As stated above i am no longer needing this 120v outlet. Thanks anyway