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How many outlets allowed in a room & light switches on same circuit as outlet?

How many outlets allowed in a room & light switches on same circuit as outlet?


  #1  
Old 07-17-09, 08:31 PM
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Question How many outlets allowed in a room & light switches on same circuit as outlet?

Basically I'd just like to know if there is some code that limits the amount of outlets in a given room or small building 12'x24'.

Also, is there a way to put light switches on the same circuit as wall outlets without the light switches turning off the outlets too?

I'm trying to save how much cable I will have to run and I was looking at my diagrams and I'd like to share current from the outlets to the light switches.. is this possible without the switches turning off the outlets too? or do I have to run separate circuits for each individual light switch and light desired to have an on/off function individually?

Are you supposed to use dielectric grease on all connections to outlets and light switches etc...?
 
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Old 07-17-09, 08:37 PM
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There is no limit on the number of receptacles on a residential circuit. There are rules for certain circuits that do not allow lighting or receptacles in other rooms. If you clarify the room more help can be given.

Yes, with exceptions, lighting can share the circuit in most rooms with the receptacles. Laundries, bathrooms and kitchens are the exceptions.

No dielectric grease is needed on the connections.

I would suggest picking up "Wiring Simplified" and reading it so you can have a better idea of basic wiring.
 
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Old 07-18-09, 12:37 AM
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Basically there is no limit in resdentail side however there may have local admendent add to it so check it out.

Normally I useally go about 15 receptales the max for both 15 and 20 amp circuit beside Kitchen and bathroom and garage and oh yeah landaury room they have spefic code allready there.

The kitchen small applanice branch circuit will required min of two circuits and it have to be GFCI protected The kitchen lighting circuit must not be on SABC at all.

Bathroom do must have GFCI receptale or breaker( 20 Amp ) in there now there is couple ways to do this if you have one bathroom all can work off from this one but if you have two bathroom or more then there is other way to do this is have one circuit for GFCI'ed receptale for all the bathroom but a major gotcha is you can not use them to hook up bathroom luminaires at all.

Landary room mantory 20 amp circuit and it will not serve outside of the landry room area.

The other thing is for most room you will have to follow the 6/12 foot rules for receptales expect kitchen SABC that shinked down to 2/4 rule

As far for garage everything must be on GFCI ( 2008 NEC code ) if you are 2005 NEC or earier the receptale must be GFCI but the luminaires are optional { unless stated something else in your local codes }

Hope that will give you basic guideline where to go from there and PCboss did mention a good book " Simpledfied Wiring " that will really help you with details what you are looking for.

Merci,Marc
 
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Old 07-18-09, 02:30 AM
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Question

Thanks for replying guys.

"Wiring Simplified" - is that at Home Depot?

I forgot to mention this. The bldg is 1 room 12'x24'. It will have 15 outlets/receptacles and 2 light switches. There will be 7 to 8 separate circuits. 2 of the circuits will be power for 1 or 2 web/database servers. I'm hoping I can pull that off with regular 20A, but wondering if I should go 240v 3 phase.... or if I even could do that with the local power co. This will be a small office and the servers I mentioned will be the most power consuming things in there besides a 42" monitor.

Think of this place like a studio with certain sections. The only thing kitchen related in there will be a mini fridge, microwave and possibly an ice maker.

No bathroom.

No laundry.

No garage.

Whats this 6/12 foot rules stuff? I can't have outlets closer than 6' ?? What if I need 2 outlets right next to each other, but on separate circuits.... as in the 2 server outlets?
 
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Old 07-18-09, 08:23 AM
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Originally Posted by searcherrr
Thanks for replying guys.

"Wiring Simplified" - is that at Home Depot?
A. this can be found in any hardware store and it will be about 12 to 15 bucks and it worth it.
I forgot to mention this. The bldg is 1 room 12'x24'. It will have 15 outlets/receptacles and 2 light switches. There will be 7 to 8 separate circuits. 2 of the circuits will be power for 1 or 2 web/database servers. I'm hoping I can pull that off with regular 20A, but wondering if I should go 240v 3 phase.... or if I even could do that with the local power co. This will be a small office and the servers I mentioned will be the most power consuming things in there besides a 42" monitor.
A. this is a commercal building or a resdentail with one room reserved for home office ? That is the main issue right there if that is legit commercal building then you must get electrician to deal with it.
That building that small you don't need three phase supply at all due you have noting that justify the three phase supply.
Think of this place like a studio with certain sections. The only thing kitchen related in there will be a mini fridge, microwave and possibly an ice maker.

No bathroom.

No laundry.

No garage.

Whats this 6/12 foot rules stuff? I can't have outlets closer than 6' ?? What if I need 2 outlets right next to each other, but on separate circuits.... as in the 2 server outlets?
The 6/12 rule is the code max distance for receptale spaceing that will cover in resedentail area however in commercal that rules will go out of window it will varies a bit depending on the layout but yes you can have two recepectales near each other.

as my other answer above is bold outside of the qoute box.

Merci,Marc
 
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Old 07-18-09, 01:56 PM
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Originally Posted by searcherrr
Thanks for replying guys.

"Wiring Simplified" - is that at Home Depot?
Yes, I believe I have seen it at Home Depot as well.

Just to try be clearer, the 6/12 rule: A device (lamp, radio, tv, etc.) may not be further away from 6' from any receptacle (outlet) Therefore the minimum spacing would be 6' from a door or other break and 12' measured along a wall. Again this is the minimum. You can pretty much put as many as you want.

No offense but - I believe three phase is a little out of your scope if you are looking to buy "wiring simplified". Best to stick with what you have now.
 
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Old 07-20-09, 02:39 PM
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You guys have just been wonderful. I really mean that.

This is on residential property and for most purposes will be for residential related stuff. There will be no customers to the residence and the servers will run some business related things, but probably only for a short time till a better facility can be utilized.

I will not have a problem then with outlet spacing because they will all have a spacing of 6' or less between them regardless of wall or break.

The question I had about the ceiling lights (just 2 of'em) was that if I hooked up to the power from the outlets (to save from running separate ceiling light circuits/cabling) I'd not want the light switches to turn power ON or OFF at the outlets as well. I didn't think this was possible since a light switch effectively creates an OPEN circuit in order to turn the lights OFF. So this is possible and WIRING SIMPLIFIED will give me that answer?


Thanks so much again. You guys are helping a lot. Hope someone can answer my light switch question now.
 
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Old 07-20-09, 03:05 PM
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Also just to clarify, the 6/12 rule applies only to finished residential living spaces (family room, bedroom, den, etc). It sounds like your building is more like a workshop in which case there is no minimum or maximum requirement on receptacles, however thoughtful placement is recommended. Is this room attached to the house or a separate building? This is important as to how you can install circuits.

Yes you may put switched lights on the same circuit as receptacles without switching the receptacles. Wiring simplified does cover this type of circuit. It is accomplished by splitting off a "branch" of the circuit controlled by the switch to supply the lighting.

Two light fixtures may be a little dim for a 24' space. What type of lighting do you intend to use? Is the ceiling flat or pitched rafters? To get office or workshop quality lighting I'd go with a minimum of four 4' fluorescents. If you're going for a different effect we can perhaps suggest different lighting options too.
 
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Old 07-20-09, 04:05 PM
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Well, the 2 lights I intend to use will be regular fluorescent bulbs. The lights will rarely be on, as the focus of work will be computer based. I will also have desk lamps and work lights on tables. Maybe I'll do 3 bulbs... or even 4. I'm wide open at the moment because there aren't even interior walls/sheetrock up yet.

The ceiling is pitched at the moment, but I was considering buying a fairly cheap (is it cork board?) ceiling that I've seen in schools/businesses that can be put together with black squared framing and the ceiling tiles (tiles i guess?) just lay into that frame and can be pushed out and in as necessary.

This is a separate building. 12'x24' in a back yard. I will be getting the electric co. to come put a 2nd cable run outside.
 
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Old 07-20-09, 11:03 PM
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Originally Posted by searcherrr
Well, the 2 lights I intend to use will be regular fluorescent bulbs. The lights will rarely be on, as the focus of work will be computer based. I will also have desk lamps and work lights on tables. Maybe I'll do 3 bulbs... or even 4. I'm wide open at the moment because there aren't even interior walls/sheetrock up yet.

The ceiling is pitched at the moment, but I was considering buying a fairly cheap (is it cork board?) ceiling that I've seen in schools/businesses that can be put together with black squared framing and the ceiling tiles (tiles i guess?) just lay into that frame and can be pushed out and in as necessary.

This is a separate building. 12'x24' in a back yard. I will be getting the electric co. to come put a 2nd cable run outside.

How far that building is from your main building ?

If relitve short like under 100 feet you can able run it from the main building breaker to run to the detached building however you will have to install the subpanel there.

Check with your POCO to see what they charge for second service sometime they will charge more than what you can able bury the conduit with conductors for subpanel.

Merci,Marc
 
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Old 07-21-09, 01:28 AM
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On the other hand, if this is a business venture then having a separately metered electrical source may be a very good idea.
 
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Old 07-30-09, 05:41 PM
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Question

I purposely want a 2nd breaker separately fed apart from the home in front. The bill needs to be separate.

It is a workshop of sorts, but I want to follow code as best as I possibly can if not 100%.

I looked at Home Depot for wiring simplified and didn't see it, but I did see "Wiring 1-2-3" which I assumed to be pretty equivalent. It has been helpful so far and I jotted down some notes to ask the forum here so here we go:

Number 1:
Load Description x Quantity x Watts x Hours =Total (Watt-hrs/day)

Computer always on......2...............110.............24..............5280
Computer sometimes on...2...............50..............3...............300
Computer on a lot.......1...............130.............10..............1300
Fluorescent bulbs.......2...............15..............10..............300
Radio...................1...............10..............10..............100
TV......................1...............150.............3...............450
CRT.....................1...............150.............2...............300
LCD Large...............1...............150.............10..............1500
A/C.....................1...............767.............24..............18408

total power requirement: 27938 watt-hours per day or 27.94 kwh
without the a/c: 9530 watt-hours per day or 9.53 kwh

Now, using the quantity and watts figures only I've figured my amps out, using the book's formula, to be: 1707 watts / 230 = 7.42 amps

From this calculation it seems to me that a 100A or 125A panel (power box, power distribution box, main circuit breaker, etc..) would be more than enough power to sustain that amperage right?

I have already diagrammed the floor plan with the furniture, receptacles, devices etc... all oriented right I have figured I need to run a minimum of 6 circuits. I wanted to leave room for expansion so I was hoping to find an 8 circuit box and I could only find that in 125A, so thats what I bought the other day at Home Depot.

Confusion though: When I tried to (Homeline is the brand. GOOD?) place 20A breakers in the box, while at the store, I couldn't for the life of me figure out how they fit in there. I was trying to put them in a vertical orientation, because thats how the spaces are lined up outside the cover of the box, but now I'm wondering if they are supposed to lay horizontal like in our current home's box. Still even in a horizontal position, I don't see how they lay in there. I don't know if you guys can even help me with that.

Number 2:
Book states that you should use 2 grounding rods (linked) for ground protection, each being 8 FEET LONG!!! How in the hell do I get those rods 8 feet into the earth? Some technique I'm missing here? I can't imagine a heavy metal sledge would work once you are like 3 or 4 feet down.

Number 3:
Code issue: If all my receptacles will all be at waist level (or about 3 feet high from the floor) does the cable run still have to be 10" above the receptacle(s)? I am using plastic outlet boxes. Ya'll think I should use metal ones? I would think the grounding rods should suffice, but opinions from experience or accidents are always desired.

Number 4:
Was going to use 20A breakers for every circuit, but should I put the light switches on 15A breakers and separate circuit? Wondering about too much flow to the bulbs.

Number 5:
If I go above 12" for cable runs I should be within all code limits?

Number 6:
Multiple cable runs on same wall: I've been told by some carpenters not to drill bigger than 1/2" holes in the center of the studs. Noted. To me this means that I can't run more than 1 cable per hole. I am using 12/2 NM B (think thats right; its got 3 wires in it). So is it ok to drill 3 1/2" holes in the studs on a wall that will have 3 circuits running to it? How far apart do these cable runs have to be from each other in the same wall?

Number 7:
Nailing Plates: I read where nailing plates are recommended over every stud side edge over where the cable runs through the middle of the stud. Is this often a common code requirement? Where might I obtain the electrical code for my locale?

Number 8:
I don't guess I have to worry about 115v receptacles being used on a 120v 20a system setup huh?
 
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Old 07-30-09, 06:46 PM
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I will start with your #2 first.

2) Ground rods are typically driven with a heavy sledge. Some contractors use an adapter on a demolition hammer.

3) The only reason is to allow the cable to be secured with a staple within 8" of a box without built-in clamps or 12" with built-in clamps. Don't sweat this distance. Nothing in the Code about this.

Grounding rods are for lightning protection and have nothing to do with device or box grounding.

4) The size of the breaker will not effect how much the bulbs draw. If the lighting circuits will be lightly loaded use #14 wire with 15 amp breakers.

5) Not an issue, see #3 above.

6) You can use a 1/2" bit, however, a 7/8 will be easier to pull the cables thru.
I try to leave 3-4 inches between holes to preserve the structural strength.

7) Nail plates are only required where you cannot maintain 1 1/4" of clearence from the stud face to the cable so it does not get hit by screws etc. If you drill in the center of a 2x4 stud with the 7/8 bit no plates should be needed.

8) 115 and 120 are the same thing.
 

Last edited by pcboss; 07-31-09 at 04:58 AM. Reason: spelling
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Old 07-31-09, 03:00 AM
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Question

Thanks for the fast reply and great answers.

Is there some technique or adapter I'm missing to getting the breakers to fit in the circuit box?

I really didn't want to have to buy 14 gauge cable and 15A breakers just for the lights.... uggg.

Under your #3 response:
"Grounding rods are for lighting protection" - did you mean lightning or lighting?
 
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Old 07-31-09, 04:57 AM
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Yes I meant lightning. I will correct my post.

Most breakers are installed by placing the feet over the mounting rail to the outside of the panel and rotating it toward the buss and pressing down to seat it. It is important to use the correct breaker type for the panel. Do you have the correct breakers for your panel?
 
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Old 07-31-09, 08:20 AM
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Originally Posted by searcherrr
Is there some technique or adapter I'm missing to getting the breakers to fit in the circuit box?
There's a tab on one side that you engage, then "roll" the breaker down into the stabs.

I really didn't want to have to buy 14 gauge cable and 15A breakers just for the lights.... uggg.
You don't have to use #14 for lighting, you can use #12 if you want to. Many of us just prefer to use #14 for lighting because it is thinner and bends easier when hooking up multiple switches in a box.
 
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Old 07-31-09, 08:31 AM
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Originally Posted by searcherrr
How in the hell do I get those rods 8 feet into the earth?
A sledge and a trusting helper to hold the rod steady. If you have tough soil, it helps to dig about 1' down with a shovel and pour a few buckets of water in the hole to soften it up before hammering. If you have rocky soil and really can't seat it, you can drive the rod at up to a 45° angle to avoid rock.

I've been told by some carpenters not to drill bigger than 1/2" holes in the center of the studs.
I always use 7/8" holes with up to two cables each. About 3" between parallel runs.

I don't guess I have to worry about 115v receptacles being used on a 120v 20a system setup huh?
In North America, the voltage is allowed to vary between 110V and 127V so anything in that range is considered the same. Most utility companies hold right around 120V.
 
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Old 08-24-09, 06:16 PM
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Thank you all, again, for your help.

Is there anything against running the cables in the rafters or hanging (security ties or plastic wire staples) them from the rafters..... or anything against running the cables along the top wall edges?

I ask this of course wondering about "code" issues and because I had a thought that if I used the ceiling space to run cable I wouldn't have to drill holes in all the studs in the walls, thus preserving the structural integrity of this small 12'x24' building.

There will be receptacles in all 4 walls so if I could use the rafters or top of wall edges it would prevent me from having to drill holes in just about every stud in the building.
 
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Old 08-24-09, 06:44 PM
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The cables are not large enough to hang from the bottom of the joists. You may run them above the bottom chord of the truss. You may find out this will take more cable than drilling thru the studs and you will still need to drill the top plates.

Drilling with a sharp bit will not take all that long, nor do significant damage to the structure. You only need a 3/4"
hole for 2 cables. Drilling the walls will stop all the up and down on a ladder too.
 
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Old 08-25-09, 06:16 PM
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Just to clarify the ground rod issue, I want to point out that the ground rods are indeed for the grounding of the devices and any equipment that is connected to electricity. Their main purpose is to bring all devices and equipment to the same potential as the earth. By bringing all the devices and anything plugged into those devices to earth potential there is not a shock hazard that otherwise could be created by a metal object becoming energized. When the outlet is grounded and the equipment is grounded, if for some reason the metal shell of a piece of equipment (a dryer for instance) was to become energized it would trip the OCPD (breaker) and prevent you from getting shocked the next time you touched it. So please by all means make sure you install those ground rods. They absolutely are not there just for lightning. They serve a major purpose.
 
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Old 08-26-09, 09:45 AM
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Are there any rules against putting receptacles underneath windows? I have 1 window on a flat wall that we'd wanted to put an outlet, but I don't know how I feel about that if the window were to ever leak.
 
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Old 08-26-09, 10:03 AM
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No problem with receptacles under windows. In fact commonly done for holiday decorations.
 
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Old 08-26-09, 10:18 AM
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Man yer great ! I'm in the building right now as we speak with my wireless laptop barely getting a signal at 11mbps. LOL Thanks!

I'm in here marking off outlet spots.
 
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Old 08-26-09, 10:41 AM
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Also, thanks UnionSparky for the grounding clarification. I figured it wasn't just for lightning, but to ground the actual appliances etc.. otherwise what else would the 3rd ground wire go to??? nothing basically...

PCBOSS - Why couldn't I use wire staples (with the screen end and a loop tie type) and staple along the bottom end of the joists where they meet up with the top end of the walls and run the cables through the staples this way? This way the staples would hold the cables just above the wall top line on the joists, but not in the center top with the chords and truss'. Is that code acceptable?
 
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Old 08-26-09, 11:09 AM
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The code is concerned about possible damage from the cables on the underside being used as a clothesline to hang things from.

Also, a breaker will trip without a ground rod. As stated before the grounding rods are for mainly for lightning. The rod does not assist in clearing a fault. Earth is a poor conductor.
 
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Old 08-26-09, 11:22 AM
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So how do the appliances, etc.. plugged into the outlets get grounded if not through the grounding rods placed outside?
 
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Old 08-26-09, 03:32 PM
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Yes pcboss is correct a breaker will trip without a ground rod. They will trip for instance on line to neutral faults. A ground rod is known as a grounding electrode. There are other forms of grounding electrodes (metal frame of a building that is in direct contact with the earth, metal underground water pipe, etc...). Without some form of a grounding electrode (250.64 in the NEC) in contact with the earth you would have what is called an ungrounded system. This was commonly used many years ago when Knob and tube was used to wire homes and other places. This practice was abandoned when it became evident that there was a danger behind not having a grounded system. The ground rod does in fact aid in clearing faults known as ground faults and even line to neutral faults (through the main bonding jumper). The ground rod creates a low impedance path to ground. Therefore when the "hot" wire comes into contact with the neutral or anything attached to the grounding system due to the low impedance a large amount of current is allowed to travel through the circuit breaker or fuse and causes the breaker to trip or the fuse blow. Without the ground rod or any other form of grounding electrode the object could become potentially energized without tripping the breaker. So to answer your question without some form of a grounding electrode your appliance or outlets would not be grounded. Grounding is a very complicated subject. To learn more about it read Article 250 of the National Electrical Code.
 
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Old 08-26-09, 07:38 PM
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The ground rod is a supplemental part of the grounding system. The water pipe is the main one which is also why it is many time required to be larger than the maximum #6 that is required to be run to the ground rod.

The ground rod have very little to do with the operation of any overcurrent device. In a dwelling that has a grounding system (aka not knob and tube) the path of a fault travels through the ground wire or grounded metal conduit to the point of connection of the grounded conductor (neutral). It does not travel outside to the ground rod, then back to the panel.
As posted earlier, the ground rod is for equaling potential between the grounding system and the earth and providing a low impedance path for lighting.
 
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Old 08-27-09, 11:56 AM
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Well, this building does not have a water pipe system going to it.

So where am I supposed to ground the "neutral bus bar" if not to the grounding rods I'd put outside?

The wiring book from Home Depot shows the neutral bus bar connected to an outside water pipe, hence my question/confusion.

I also am realizing my understanding of circuit breakers was a lil off in that it looks like you only connect 1 black wire to them and the other wires to the neutral bus bar for normal outlets/switches etc..
 
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Old 08-27-09, 12:04 PM
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Your grounding should come in your 4 wire feeder from the panel in the other building.

You do however still need a ground rod at the outbuilding.
 
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Old 08-27-09, 05:04 PM
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Your neutral buss should not be connected to any grounds since your panel will be a sub panel. You should also not bond the panel can with the strap or bonding screw. You will need to install a separate ground bar that all your grounds will attach to.
 
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Old 08-28-09, 09:26 AM
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Ok, someone please clarify cause I think ya'll have got this figured out wrong.

I am not connecting to the other building in any way. This building is to be completely separate from the other building. I am installing a MAIN PANEL, not a SUB PANEL. So all my questions are based around that.

In addition to readdressing the last few posts in that mindset, I also need to know how I should or shouldn't mount the MAIN PANEL. Some of what I've read says to place it over sheetrock and others show it on plywood. What up?
 
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Old 08-28-09, 09:44 AM
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As far as the grounding without a metallic water line to the house you would need to drive 2 8' grounding rods no closer than 6' apart. There are also other options available but ground rods are the most common. The wire to the rods only needs to be #6 unless subject to damage.

Are you surface or flush mounting the panel?
 
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Old 08-28-09, 10:42 AM
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He lives in SE Louisiana. He can probably push an 8' grounding rod in by hand without beating on it if he uses a few cups of water to help get it started.
 
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Old 08-28-09, 11:10 AM
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Thanks PCBOSS for the clarification there.

I guess I haven't realized how hard other area's soil is. After the first foot here its pretty moist, but 8 FEET is a long rod and a lot of surface area to push past. I was just concerned that I wouldn't be able to beat it down there.

So once I get these rods in proper position SINCE I'M CONNECTING A MAIN PANEL I WILL CONNECT THE GROUND RODS TO THE NEUTRAL BAR IN THE MAIN PANEL? CORRECT OR INCORRECT?

I would like the panel to be FLUSH mounted (assuming this means inside the wall with the face of it flush with the sheetrock) however I could mount it on top the sheetrock (with the back of the panel on top the sheetrock; SURFACE?) if that is better to do. There is really no concern of visuals/eye sores here. I really would rather mount the MAIN PANEL in the safest configuration possible.

Right now there is no insulation or sheetrock up. Just looking at the exterior wall with the studs from the inside. I have about 14.5" of space and the PANEL measures 14" exactly, SO I GUESS I HAVE TO GET SOME SHIMS IN THERE TO MOUNT IT FROM THE LEFT/RIGHT? Should I put 2 small 2x4's above & below the panel too to make it a snug fit?

The book I have says to mount subpanels atop a non-conductive non-fire material like sheetrock, but then there are pictures of panels in other pages against plywood or 2x4 studs too, hence why I'm confused at which is better or what the code is for this. I guess what this probably means is it doesn't matter as long as the panel isn't touching any metals?
 
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Old 08-28-09, 11:22 AM
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I live in SE Texas, so my soil is probably similar to yours (black gumbo). I've installed four 8' ground rods at my house over the years, and I've never had to beat on one to get it all the way in. And no...I'm not young and/or big and/or strong. The ground rods (at least the ones I used) have a pointed end to make it easy.

I don't know how to describe it, but you don't just try to push it in all at one time in one motion. Once you get it started, lift it up a few inches then push it down quickly. Then lift it up a few inches again and push it down quickly again. Repeat over and ove till it's in. It should go several inches further each time. If it doesn't, pour a little water around the rod and let it seep to the bottom of the hole. If you let the weight of the ground rod (and its pointed end) do the work, it is pretty easy to do.
 
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Old 08-28-09, 11:50 AM
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You Texans are pretty close enough to know about gumbo huh? lol - Texas sure is nice. I'm glad to know it should go in the ground easy.

So Broussard (sounds like a LA name man) did you hook those ground rods to your neutral bus bar in the main panel or where to?

I mean, I don't see what else I'd hook it to giving that I'm putting in a MAIN PANEL. The book shows the neutral bus bar going to a cold water pipe, so since I don't have that it would make logical sense to me that I should use the grounding rods instead? RIGHT? WRONG? I know the book shows this to me, but I like bouncing it off people.
 
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Old 08-28-09, 12:01 PM
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Since you are setting a service the bond screw will be installed.

The conductors to the rods will terminate on the neutral buss.
 
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Old 08-28-09, 12:42 PM
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Originally Posted by searcherrr
You Texans are pretty close enough to know about gumbo huh? lol - Texas sure is nice. I'm glad to know it should go in the ground easy.

So Broussard (sounds like a LA name man) did you hook those ground rods to your neutral bus bar in the main panel or where to?

I mean, I don't see what else I'd hook it to giving that I'm putting in a MAIN PANEL. The book shows the neutral bus bar going to a cold water pipe, so since I don't have that it would make logical sense to me that I should use the grounding rods instead? RIGHT? WRONG? I know the book shows this to me, but I like bouncing it off people.
I was born in Lafayette, but moved to TX in 1956 when I was two years old.

My ground rods weren't all for the electrical system, although they were all the same size. One was for an electric fence transformer. One was to ground a DirecTV satellite dish (I don't have metal pipes to ground to). One was requested by the phone company to ground the phone wires because my electrical system ground rod is 150' from my house near the meter loop and there wasn't a ground on the outside of the house that the phone lines could be tied into (the panel in the house is set up as a subpanel so it doesn't have its own ground rod).

The one ground rod I have for my electrical system (I only needed one at the time 20 years ago, don't know about that now) has a single cable running to the ground bar in my service entrance panel (maybe five feet of cable). Mine is a little more complicated than most because I also have a whole house standby genset (hurricane country), which includes an automatic transfer switch that doubles as my service entrance panel.

The way I understand it (and I'm not an electrician, and I'm sure there are exceptions) is that since your new panel is completely separate/isolated from you house panel (you have a different meter loop and everything), if your panel has a separate neutral bar (for the "white neutral wires"), it must be grounded to the panel. There's usually a green screw near the top of the neutral bar that if screwed in makes a bond between the neutral bar and the panel. I've also seen ground straps that run from one of the holes in the neutral bar to a screw on the panel. The only wire that goes to the ground rod is a single wire from the ground bar (if your panel has separates), or a single wire from the ground/neutral bar (if your panel doesn't have separates). If your panel contains separate neutral and ground bars, they must both be grounded to the panel in some fashion, which means they are electrically connected to each other in the panel.

Just remembered...I have one more ground rod next to my genset. It's connected to the genset frame.
 
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Old 08-28-09, 02:15 PM
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So the "bond screw" is probably gonna be a green screw meant for connecting the neutral bus bar to the 2 8' grounding rods I will install?
 
 

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