Need Help Building a sub panel...

[PoopyTeaBags]

ok guys im no electrician but ive been running new lines for a few years... i know pretty much what guages i need for everything(for the most part).

So the last place i just help set up set this 30a subpanel up and it seems pretty basic shit.

So now im setting up another person and want to run a 40a subpanel.

So basically what i would do is just get a sub panel a 40a 240 breaker 8guage? or 10 guage wire.. and the wire hooks up into the subpanel and from there i should just be able just install breakers and run new lines. correct...

please if im wrong on something let me know without the flames i understand that this is serous and wouldnt be taking it on if i thought i couldnt do it how ever im gonna do as much research as possible before i install it.

 

[eddie.saw]

that all sounds good to me, it's been a few months since i graduated or done anything but all sounds spot on!

 

[dtfsux]

according to my Uglys book (its a quick reference guide sold at Home Depot, etc, based on NEC code), you can use 10 gauge if its copper and if its THHN or a few other kinds of wire.

I would just use #8 copper and be safe. according to Uglys, any #8 copper will work.

Aluminum has lower capacity and it depends on the type of wire.

 

[highgrade]

I'm not sure what you mean by a 240 breaker? With a 40 amp sub panel you should run 8ga wire. Your panel will have a 40 amp main breaker, then breakers for each run from the sub panel.

 

[PoopyTeaBags]

by a 240 breaker i mean a double pole breaker...

 

[Oregongrow]

http://www.selfhelpandmore.com/home...o-dwellings/wiring-a-detached-garage-2002.php

 

[highgrade]

by a 240 breaker i mean a double pole breaker...

Double pole 40amp for the main, then what do you want to run off the sub panel? 2-20amp circuits, 40amp 240v with relay to control lights? Need a little more info to help.

 

[PoopyTeaBags]

well once i actually get the 40 a main hooked into the breaker box i know exactly what im doing....

Unless i hardwire a intermatic timer on it which i might... but even then it just act like a junction box sort of right... i just go from breaker to timer to a junction box to my plugs correct?

 

[joe fresh]

is this sub panel for lights only? if so you could wire your timer between your main panel and your subpanel, then put the breakers you need your your lights, run wire from breakers to where you want your ballasts, and fix a plug on it or hard wire it directly.

 

[highgrade]

well once i actually get the 40 a main hooked into the breaker box i know exactly what im doing....

Unless i hardwire a intermatic timer on it which i might... but even then it just act like a junction box sort of right... i just go from breaker to timer to a junction box to my plugs correct?

You put the 40amp breaker in your main panel, run 8ga to your sub panel (sub panel feed). You would need breakers for what ever circuits you are running off the 'sub panel'. That would be a 'sub panel. Depends on where you're going with the power, but using the panel as a junction box would leave all circuits protected by the 40amp breaker in your main. Are you in a 240v country cause I'm still not understanding exactly what you're trying to do.

 

[PoopyTeaBags]

THis is what im doing 40a main for sub panel Then ill be running 30a double pole breaker to a hardwire intermatic timer. Then ill run junction box and split it up to two 240 20a plugs.

Then Im gonna run a 15a 120 to a plug daisy chained for a 4plug out let.

Ill use 8g wire to run the 40a and if it dont matter ill run the 8 guage for the hardwire of timer and junction box to the plugs... Is that ok...? running a bigger guage then needed dont matter correct?

Then ill run a normal 12guage for the 15a 120.

Does that all sound correct... hopefully thats explained alot better.

 

[highgrade]

THis is what im doing 40a main for sub panel Then ill be running 30a double pole breaker to a hardwire intermatic timer. Then ill run junction box and split it up to two 240 20a plugs.

Then Im gonna run a 15a 120 to a plug daisy chained for a 4plug out let.

Ill use 8g wire to run the 40a and if it dont matter ill run the 8 guage for the hardwire of timer and junction box to the plugs... Is that ok...? running a bigger guage then needed dont matter correct?

Then ill run a normal 12guage for the 15a 120.

Does that all sound correct... hopefully thats explained alot better.

40amp=8ga
30amp=10ga
20amp=12ga
15amp=14ga

That's standard. Sounds like you're building a timer box?

 

[PoopyTeaBags]

If i was to put the timer BEFORE the subpanel it would be a timer box.. Since im putting it after it allow me to throw 120's that are not timed to the timer of the lights. but essentially its for my lights.

 

[sparkjumper]

Man you should wire your subpanel to a little gray box hot water heater timer and from there to a 4 inch square box holding your receptacles.Most subpanels are just main lug panels not utilizing a main breaker.They call those main breaker load ctr and without a main breaker in the subpanel its called a main lug panel.I wouldnt use a main breaker panel for a subpanel but thats me

 

[Bigrick31]

If youre running your sub panel or (Main lug panel) off of your main electrical panel in your house then you essentially have main breakers to your sub panel that are just located back at your main house panel electrically its all the same. Just a matter of walking a bit to turn the sub panel off vs having the breakers right there.

To the OP 8 gauge wire and a 2 pole 40 amp breaker will work just fine for your sub panel. Then take all your branch circuiting from your new 40 amp sub panel.

 

[sparkjumper]

Exactly what I was thinking,the circuit going to the subpanel has overcurrent protection from the main house panel.I wish people would look into the intermatic wh-40 to supply the receptacles with power,I hope I'm not getting like a broken record.That external on off lever is just about the best quick disconnect you can have in that situation.Note the WH40 is rated at 40A but you can run many 1K fixtures at 240V

 

[Bigrick31]

That timer looks killer to me id use it if my timers wernt computer controlled.

 

[tokinafaty420]

poopy you sound to have it under control. I use the same thing, except my subpanel is being fed by a 60a 240v double pole. I did not use the little gray box timers tho, instead I went with 20a digitals that you hardwire the same way you would "LGB". Obviously I used larger gage wire as well.