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-   -   Does it matter how close your panel is to your meter? (http://www.diychatroom.com/f18/does-matter-how-close-your-panel-your-meter-29851/)

jamiedolan 10-13-2008 05:16 AM

Does it matter how close your panel is to your meter?
 
I will have a electrician in to help me with this, but would like to find out if it is possible because I will run the conduit if it is.

I would like to move my meter to a different location on my house, I am working to figure out if this is possible, assuming it is, my question is; with the meter moved, the meter would be about 40 feet away from the panel. If I ran say 2" pvc (grey electrical) conduit from the meter to the electrical panel, could the main run in that conduit for the 40' feet from the meter to the panel?

Any reason I could not do this? Is 2" too small?

(200A service)
Thanks
Jamie

napper 10-13-2008 06:25 AM

My meter is 135 feet from my panel. BUT, I installed a 200 amp breaker directly below the meter. That way my 135 ft. is a feeder not a service entrance. The code looks at feeders entirely different than services.

kbsparky 10-13-2008 06:31 AM

Would that conduit be located inside or outside?

If the conduit is installed outside, then you might not need an outside disconnect, and your inside panel could remain as your "service" -- with the grounds and neutrals connected together.

If the conduit is installed inside, then you might need an outside service disconnect, making your inside box a sub-panel. In this scenario, you would need to install 4 conductors in the conduit: 2 hots, one neutral, and an equipment grounding conductor.

We install (2)-4/0 XHHW AL conductors for the hots, a 2/0 neutral, and a #4 EGC. Back in the old days when copper was reasonably priced, we used (2)-2/0 THHN/THWN hots, a 1/0 neutral, and a #6 EGC.

All your grounds would have to be separated from your neutrals, and the neutral box bonding screw or jumper would have to be removed.

We install feeder conduits like you have described all the time. Mostly on modular houses, where the factory installed panel is located on an inside wall.

We utilize a meter/main box for such installations. It has a 200 Amp meter socket, 200 Amp main breaker/disconnect, space for up to 8 full size breakers, and feed-thru lugs for your sub-feed to the inside panel. A typical Square D box looks like this:

http://ecatalog.squared.com/pubs/Ele...0CSED_lres.jpg

Termite 10-13-2008 09:21 AM

KBSparky's right. Per NEC 230.70(A)(1)...

The service disconnecting means shall be installed at a readily accessible location either outside of a building or structure or inside nearest the point of entrance of the service conductors.

The whole idea is that you don't want to have line current running in the house, because it isn't protected by an overcurrent device...And it is BIIIIIG amperage.

It ultimately comes down to your inspector, as the NEC leaves this somewhat open to interpretation by not giving an exact permissible distance. I'll allow maybe ten feet. Beyond that, we're going to require a disconnecting means/overcurrent device outside by the meter.

jamiedolan 10-13-2008 09:28 AM

Quote:

Originally Posted by kbsparky (Post 171667)
Would that conduit be located inside or outside?
All your grounds would have to be separated from your neutrals, and the neutral box bonding screw or jumper would have to be removed.

We install feeder conduits like you have described all the time. Mostly on modular houses, where the factory installed panel is located on an inside wall.


The conduit would be inside the crawl space, which is a heated part of the house.

I was going to run copper even though it is expensive, I have heard too many no so great things about AL.

What do you mean have keeping the grounds separate from the neutrals? Do you actually have a grounding bar in your box and a neutral bar, and you have to connect the neutral and the ground to each bar seperatly? or am I getting confused with what you describing?

I would be able to use the same CH42 space panel as a sub right?

Thank You
Jamie

Termite 10-13-2008 09:36 AM

You'd need to set a 200 amp disconnect outside by the meter. That will become your "main", and your grounding (water line, rod, etc) and bonding will take place there, not at the panel in the house. The panel you have can serve as a subpanel in the house, and the copper wire in the crawlspace becomes a feeder (it is now fused).

The subpanel in the house will wire a little differently, as mentioned. The neutrals and grounds are isolated, and the neutral bar does not bond to the panel jacket. This is referred to as "floating" the neutrals. Basically, you have a ground bar and you have a neutral bar, and they're not bonded together.

handyman78 10-13-2008 09:59 AM

Quote:

Originally Posted by jamiedolan (Post 171685)
I was going to run copper even though it is expensive, I have heard too many no so great things about AL.

What do you mean have keeping the grounds separate from the neutrals?

Jamie- there is nothing at all to be concerned about with using AL as a service entrance conductor either in a SE cable or individual conductors. All home in my city use just that to supply electric from the power companies. You would need 4/0 cable between your meter and the 200a breaker. Copper while a nice conduction path and allowed a few sizes smaller is very cost prohibitive especially in that size. Just be sure the connections are cleaned and use Noalox to prevent oxidation.

Regarding point 2- once your electrical service comes from your meter, it is considered unprotected from overcurrent. That is why you need a short distance between the meter and main breaker often 10 or less feet depending on local codes. If your service entrance panel will be a distance from your meter, you could either use a combination meter/service entrance panel which eliminates the problem or a disconnect box either including or just past the meter with only a 200a breaker inside. Anything past this breakerbox then becomes a sub-panel and must be wired accordingly- using 4 conductor cable 2 hots, 1 neutral, 1 ground and the ground and neutral MUST be kept seperate in that box. The box will be bonded to the ground bar and have all ground connections while the neutral bar will stay isolated from the box and ground bar and only have the neutral or white wire connections.

kbsparky 10-14-2008 08:05 PM

Quote:

Originally Posted by jamiedolan (Post 171685)
The conduit would be inside the crawl space, which is a heated part of the house.

In that case, you will definitely need an outside disconnect. The combo box depicted earlier would be a good choice in such an installation.

Quote:

I was going to run copper even though it is expensive, I have heard too many no so great things about AL.
The price of copper is falling quite nicely these days. If you can stomach the price, then by all means go for it! You could use a 1" conduit with copper feeders. I'd still go with a 2" in most cases, but we have installed them in a 1 where it was too tight to get that 2" conduit in a tight space. :whistling2:
Quote:

What do you mean have keeping the grounds separate from the neutrals? Do you actually have a grounding bar in your box and a neutral bar, and you have to connect the neutral and the ground to each bar seperatly? or am I getting confused with what you describing?
The only place your neutrals and grounds can legally be connected together is at the service. Using an outside disconnect as you would be required to do here would make that the service point. Anything located downstream would have to keep the neutrals separated from the grounds, as explained by thekctermite.

Quote:

I would be able to use the same CH42 space panel as a sub right?...
Yes, just be sure to remove the bonding jumper from the neutral bar. It's a small copper jumper between a green screw and the neutral bar. Be sure to reinstall that green screw once the copper jumper is removed to maintain the enclosure bonding integrity.

Install all your neutrals on the one side, and the grounds on the other side, keeping your grounds on the side with the enclosure bonding strap.

NOTE TO LURKERS: These instructions are specific for Cutler-Hammer panels, regarding the separation of the grounding bar from the neutral.

jamiedolan 10-17-2008 09:17 AM

Thank You
 
Thank you everyone for your assistance on this topic. I apologize I was ill and was not able to respond for a few days.

I do understand your directions, Thanks.

For the outside disconnect, can I use any outside rated panel / 200A disconnect or do I need to use a combo box? I just have not seen a combo box for sale, but have seen a number of outside rated panels for a good price.
Thanks
Jamie

kbsparky 10-17-2008 09:31 AM

You don't have to use a combo box. We use them because they're cheaper than having to buy a meter box and an outdoor disconnect, and you don't have to nipple them together and wire `em up.

But just to be sure, ask your utility if they would approve one before buying it.

As for where to get one, I bought a bunch at my local Home Depot. While the local store did not carry it in stock, they were able to special order one in, and at a very reasonable price.

The catalog number I bought was a Square D RC816F200CH.

Tuckahoe Sparkplug 10-18-2008 05:38 AM

Quote:

Originally Posted by thekctermite (Post 171688)
You'd need to set a 200 amp disconnect outside by the meter.

This is correct. Just be sure it is a fusible disconnect as opposed to a non-fusible disconnect. It can either have fuses or a circuit breaker.


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