Ground connection

frank otero · 02-14-2011, 05:53 PM

Hello,

I was not able to load the national code links featured on the sticky above.

As I look at my breaker box, I see three wires coming in from the street. Two go into the main area of the breakers (assume these are 120 each) and the other go to the neutral bus (where white colored wires feed). However, there is nothing going to the ground bus, and I do not see anything connecting the ground bus to the neutral bus.

Should I have a dedicated wire going into the ground bus connecting it straight to the earth rod?

dhubz · 02-14-2011, 06:33 PM

your post doesn't say where you are, but here in ontario, it depends on if you are city or rural. If you are in the city you need a wire from your neutral to your water pipe cityside of your water meter, if you are in the country you can use a ground plate or 2-10' ground rods, then bond your water pipe to the groundbar in your panel. In your panel there should be a black screw in your neutral bar, this is your bond screw, it connects the neutral to ground via your panel enclosure, sometimes there is a jumper that connects your neutral bar to ground.

Speedy Petey · 02-14-2011, 07:08 PM

Be reminded, a water pipe bond or electrode, or a ground rod or plate, or any other electrode, is NOT where your "ground" comes from in your panel. These items serve another purpose entirely.
The ONLY place your equipment ground comes from is the neutral/ground bond described above. This can be in several forms as described, such as a screw, strap, or the bars screwed directly to the panel box.

frank otero · 02-14-2011, 07:12 PM

Thanks for your response.

This came about as my gas stove electronics have been acting up and the company claims that it needs and independent ground. The tech says I am missing a wire coming in the breaker box - should be four instead of the three in there now. One to the ground bus bar, one to ground and two hot.

AllanJ · 02-15-2011, 08:56 AM

Does the branch circuit cable coming from the stove receptacle have a ground wire? Check to be sure it is connected properly including at the stove receptacle.

Electronic equipment can have an informal ground, a bare wire daisy chained from one piece to the next using some connection such as a screw that goes into the chassis. Connect the far end to a known ground which can be a water pipe that is all metal down into the basement and to the cold water line entering the house where in turn there needs to be a (#6 for 100 amp or smaller electrical services) copper ground wire to the breaker panel frame or ground bus.

At the first panel where there is a switch or breaker that shuts off the entire power feed, there are just three wires coming in, the two hot wires for 120/240 volts and one wire that serves as both neutral and system ground. The latter has to be bonded in some fashion to both the neutral and ground busses. Such bonding is normally accomplished by having the wire connected to the neutral bus or a piece of metal hanging off of it, and the neutral bus has a screw digging into the back of the panel itself or a wire or copper strip going to the ground bus or attached to the back of the panel. The system ground is connected to ground rods at most if not all of the utility poles but must also be connected to a wire going out from the panel to the main water pipe or to a ground rod at your house.

frank otero · 02-15-2011, 03:15 PM

Thanks Allan,

My box does have the three wires (quite thick) coming in and distributed as you mentioned. There is a copper leg from the neutral bus screwed into the panel.

I got continuity between ground bus bar and neutral bus bar in the panel.

Took the junction box apart that feeds the stove, disconnected all wires, and got continuity between ground (bare) wire and service panel and between neutral and ground wires. My gas line (stove is gas and electric) also showed grounded.

I am starting to think the stove is properly grounded.

a7ecorsair · 02-15-2011, 06:33 PM

Quote:

Originally Posted by frank otero

Thanks for your response.

This came about as my gas stove electronics have been acting up and the company claims that it needs and independent ground. The tech says I am missing a wire coming in the breaker box - should be four instead of the three in there now. One to the ground bus bar, one to ground and two hot.

How did the tech know your panel only had three wires? You didn't let him remove the panel cover, did you?
Did he say where this missing forth wire should be connected? You do have a large bare wire connected to the ground bus, yes? That is wire # 4

frank otero · 02-15-2011, 07:32 PM

Quote:

Originally Posted by a7ecorsair

How did the tech know your panel only had three wires? You didn't let him remove the panel cover, did you?
Did he say where this missing forth wire should be connected? You do have a large bare wire connected to the ground bus, yes? That is wire # 4

He did look in the panel. There is no wire coming into the panel from outside the house connected to the ground bus.

From all I have put together, it seems that three wires is all that is required for my installation (one main panel, no sub-panel). For some reason he felt 4 wires is the code.

a7ecorsair · 02-16-2011, 03:06 PM

Yup, 4 wires is correct - two hots, a neutral, and the GEC (ground).

AllanJ · 02-16-2011, 03:44 PM

Quote:

Originally Posted by frank otero

For some reason he felt 4 wires is the code.

Do you lack a wire running from the panel to the entering cold water pipe?

frank otero · 02-17-2011, 02:17 PM

Quote:

Originally Posted by AllanJ

Do you lack a wire running from the panel to the entering cold water pipe?

I am not gronded to the water pipe (I am all pex anyway and on a well), but to a rod in the ground next to the electric meter. The wire coming from that rod goes to the neutral bus bar. There is no wire coming from outside the house to the ground bus bar. I have been told that this is correct (only three wires) and that the ground bus and the neutral bus are connected through the panel box (there is a copper leg screwed from the neutral bar to the box).

I amy put a wire between ground and neutral bars for sheeeet and giggles, but all the tests have shown that my sytem is grounded.

a7ecorsair · 02-17-2011, 06:42 PM

You have a correctly wired service. 2 hots, 1 neutral, and 1 ground. Believe it or not, that is 4 wires. The guy who told you that there should be 4 wires should limit his electrical troubleshooting to broken flashlights.

AllanJ · 02-17-2011, 07:58 PM

The wire going to the ground rod is your fourth wire.

It may connect to either the neutral bus or the ground bus given that this is the panel with the main disconnecting switch and the neutral and ground busses are bonded to each other (here, via the panel metal)

Stubbie · 02-17-2011, 09:19 PM

Quote:

Originally Posted by AllanJ

The wire going to the ground rod is your fourth wire.

It may connect to either the neutral bus or the ground bus given that this is the panel with the main disconnecting switch and the neutral and ground busses are bonded to each other (here, via the panel metal)

Actually the grounding electode conductor entering the service equipment must terminate to the terminal or bus to which the service grounded conductor terminates. Terminating the GEC at the service equipment to a grounding bus is a code violation.

frank otero · 02-18-2011, 09:00 AM

Quote:

Originally Posted by Stubbie

Actually the grounding electode conductor entering the service equipment must terminate to the terminal or bus to which the service grounded conductor terminates. Terminating the GEC at the service equipment to a grounding bus is a code violation.

If I get what you are saying..... The wire coming in the service panel that is attached to the grounding rod in the dirt outside needs to go direct to the ground bus bar? Then the neutral bus bar will be grounded through the metal in the panel?

Can I just run a wire between ground and neutral bus bars, leaving the rest the way it is now (ground wire from outside the house is attached to the neutral side)?

Can someone point to the section of the code that covers this?

PS. I only have one panel...no sub panels

thank you all for the responses

02-14-2011, 05:53 PM	#1
frank otero Newbie Join Date: Jan 2011 Posts: 24	Ground connection Hello, I was not able to load the national code links featured on the sticky above. As I look at my breaker box, I see three wires coming in from the street. Two go into the main area of the breakers (assume these are 120 each) and the other go to the neutral bus (where white colored wires feed). However, there is nothing going to the ground bus, and I do not see anything connecting the ground bus to the neutral bus. Should I have a dedicated wire going into the ground bus connecting it straight to the earth rod?

02-14-2011, 06:33 PM	#2
dhubz Member Join Date: Nov 2010 Location: Ontario Posts: 33	Ground connection your post doesn't say where you are, but here in ontario, it depends on if you are city or rural. If you are in the city you need a wire from your neutral to your water pipe cityside of your water meter, if you are in the country you can use a ground plate or 2-10' ground rods, then bond your water pipe to the groundbar in your panel. In your panel there should be a black screw in your neutral bar, this is your bond screw, it connects the neutral to ground via your panel enclosure, sometimes there is a jumper that connects your neutral bar to ground.

02-14-2011, 07:08 PM	#3
Speedy Petey Licensed Electrical Cont. Join Date: Feb 2004 Location: NY State Posts: 6,202	Ground connection Be reminded, a water pipe bond or electrode, or a ground rod or plate, or any other electrode, is NOT where your "ground" comes from in your panel. These items serve another purpose entirely. The ONLY place your equipment ground comes from is the neutral/ground bond described above. This can be in several forms as described, such as a screw, strap, or the bars screwed directly to the panel box.

02-14-2011, 07:12 PM	#4
frank otero Newbie Join Date: Jan 2011 Posts: 24	Ground connection Thanks for your response. This came about as my gas stove electronics have been acting up and the company claims that it needs and independent ground. The tech says I am missing a wire coming in the breaker box - should be four instead of the three in there now. One to the ground bus bar, one to ground and two hot. Last edited by frank otero; 02-14-2011 at 07:20 PM.

02-15-2011, 08:56 AM	#5
AllanJ Member Join Date: Nov 2007 Location: Nashua, NH, USA Posts: 6,775	Ground connection Does the branch circuit cable coming from the stove receptacle have a ground wire? Check to be sure it is connected properly including at the stove receptacle. Electronic equipment can have an informal ground, a bare wire daisy chained from one piece to the next using some connection such as a screw that goes into the chassis. Connect the far end to a known ground which can be a water pipe that is all metal down into the basement and to the cold water line entering the house where in turn there needs to be a (#6 for 100 amp or smaller electrical services) copper ground wire to the breaker panel frame or ground bus. At the first panel where there is a switch or breaker that shuts off the entire power feed, there are just three wires coming in, the two hot wires for 120/240 volts and one wire that serves as both neutral and system ground. The latter has to be bonded in some fashion to both the neutral and ground busses. Such bonding is normally accomplished by having the wire connected to the neutral bus or a piece of metal hanging off of it, and the neutral bus has a screw digging into the back of the panel itself or a wire or copper strip going to the ground bus or attached to the back of the panel. The system ground is connected to ground rods at most if not all of the utility poles but must also be connected to a wire going out from the panel to the main water pipe or to a ground rod at your house. __________________ The average homeowner who lost his house in the Oklahoma tornadoes should move for good and not rebuild. Too much complexity watchdogging the contractor. Too much a chance to be defrauded. Last edited by AllanJ; 02-15-2011 at 09:17 AM.

Ground connection