main breaker panel configuration

[wirenut]

i am wiring a new house and installing a square d 200 amp main service panel. out of the box the two neutral buses are joined. i plan to install parallel add on buses mounted directly to the panel for my separate ground. so the white would go to the neutral bus and the bare copper to the ground bus. is this correct.
second question. i plan to use 2/0 copper thhn entrance cable for the two hots and the neutral. what do i use for the ground wire and how do i get it into the box.
thank you.

[mdshunk]

With regards to ground wire size for service equipment, you need a #6 copper to the ground rod(s) and a #4 copper to the cold water pipe within 5' of where it enters the building (if one exists). I generally just bring them in a knockout hole. Most panels have a few real small knockouts for the ground wire.

You said this is a service panel. If this is in fact service equipment, then you need to install the green bonding screw that comes with the panel in the neutral bar, so that the neutral bar in bonded to the box. The grounds and neutrals all terminate on the same bar(s) in service equipement. You should have plenty of "holes". If you have a seperate service disconnect right after the meter, then this is not a service panel at all... it would just be a subpanel. In that case, neutrals and grounds must remain separated and the bonding screw left out and a ground bar kit(s) installed.

[wirenut]

thnak you for the clarification. the main disconnect is in the meter service panel on the outside of the house so i guess this is a sub panel. the two panels will be basically back to back. i plan on using the rebar grid in the fooring as the ground. from what i have pieced together in my readings, i would use the 2/0 copper for the two hots and the neutral from the load side of the main disconnect on the meter panel. i plan to use #4 copper bare ground from the grounding circuit (rebar) and bring this in to the main sub panel to the ground bus. i also plan on using a breaker in the meter panel as the main disconnect for my outside air conditioner unit since it is within 6 feet of the panel. is this okay. so much to keep up with. this site and the wonderful articles are so helpful. thanks for the reply

[mdshunk]

Do you really have rebar in your floor? Maybe in the footers. I'd have only thought you would have had #6 wire mesh. I have *zero* experience using rebar (or wire mesh) as the grounding electrode. I *think* these systems have to be engineered ahead of time with grounding in mind (extra tie wires and tie wires made up extra tight). I'm interested to see what develops in this thread from that thought. Is there some major objection to driving a couple of ground rods? I'm not sure what the approved connector for copper wire to rebar is. I would think you'd have to CadWeld it with a CadWeld kit. Since your panel and your service disconnect are so close, I'd put a breaker in the panel and feed the a/c through a breaker. I think that "just because it's allowed" is not a good enough reason to double lug the main disconnect to feed the condensing unit. I'm beginning to wonder in the back of my mind if this is a real post or not? Nearly every sentence sounds like "bait". Seems like you're gonna need at least 3/0 copper, also. The 2/0 you're wanting so badly to use is only okay for about 175 amps.

[wirenut]

the rebar is in the footing. fooring was my misspelling, sorry. yes the rebar was tied good with the anticipation of using it for the ground. in fact it is required in our local code because of the rocky conditions and people were not able to drive grounding rods far enough into the ground and would therefore cut them off when they could no longer drive them any deeper.
on the 2/0 copper for the 200 amp service, i read in mr. goodrich's article on wiring meters,etc. that 2/0 copper was the choice for 200 amp service. did i read this wrong.
on the air conditioner main breaker being in the meter panel maybe i wasn't clear but my meter panel is the type which has the 200 amp main disconnect and space for six breakers all of which can be accessed from outside the house. this is required here also so the fire department or emergency people can cut the power without having to enter the building. from what i know, the a/c can work off of a breaker installed in this outside panel if it is close enough to the unit.
no, i am not fooling you. i obviously don't know as much as you do and am asking for help and advice.

[mdshunk]

Sorry, wirenut. Sometimes I get thoughts and I'm better off biting my tongue (or keyboard finger in this case). It hasn't happened yet on this site that I know of, but sometimes folks will ask loaded questions that they know the answer to, in an effort to "stir the pot". As for the 2/0 and 3/0 thing. If Wg says 2/0, then 2/0 it is. I was just going off the top of my head on that one.

[Wgoodrich]

See NEC Table 310.15.B.6 for residential service conductors declaring 2/0 copper approved for 200 amp service in a dwelling.

HOpe this helps

Wg

[wirenut]

okay, thanks for the clarification on the 2/0 service cable. next step: i have run from the outside meter pan which contains the main disconnect into the main service panel for the whole house which is i guess is a sub panel by definition. in this sub panel do i run the white neutral wires to the neutral bus and the bare copper ground to a separate bus ( a ground bus). since the ground bus is screwed directly to the sub panel is there any other bonding that i have to do. do i run the # 4 copper ground wire to this bus only. thank you
oh, do i have to bring the ground wire into the meter panel?

[Speedy Petey]

All the grounding electrode conductors must go to the main panel. The outside panel in your case.
Do you have municipal water with a metal pipe entering the building?

[wirenut]

i have copper pipe in the slab but it will be pvc from the meter to the house.
all grounds to the main panel? do i then run them into the sub panel from there? thank you