Ground and Neutrals

If the only electrical panel at the home is the main panel located at the exterior with a main breaker of 125 Amps and all of the breakers for the home located under the main breaker in that same panel, do the ground wires and neutral wires need to be on separate buss bars?
Also if a surge suppressor is wired in, does the suppressor need to go to its own breaker or is it acceptable to wire the surge suppressor in with the main wiring from the meter?

Paul, the ground and neutral wires don’t need to be on separate bus bars, in the service disconnect panel, but the separate bus bars need to be bonded together and to the panel board.

What if the main panel is the only panel?

The main, the only panel, is the service disconnect panel. The buss must be separated in an additional box (sub-panel) wired down-line from the main.

Where is the surge supressor installed?

In the main panel, which is the service disconnect panel, the neutrals and grounds are bonded together.

Doesn’t sound like a safety or code issue [per NEC]. However, local codes might require(desire) separate bars.

Now this has me concerned. Rather than get into the different manufactures installation instructions, I have a Square-D surge breaker, this could be a universal concern. Is there wires coming from the meter base, and the surge protector under the main lugs? Do you see two wires under one screw?

tom

Paul,

 The MAIN PANEL which houses the MAIN DISCONNECT is the location at which the Grounded and the Grounding Conductors will be tied together on the same terminal buss...if they are not a bonding jumper must be installed to ensure they are tied together.

  To avoid confussion....remember now from this point into the house...if you have ANY other panels.....you must have (4) conductors which involves a sererate grounded conductor and EGC......both of which MUSt terminate on a seperate terminal bar.......the grounded ( neutral conductor ) must remain FLOATING and not in direct contact with the metal enclosure.....

Now…as for the Surge Suppressor…many in the past used to put them under the main lugs…but since the main lugs were not designed to handle multiple conductors…it was wrong an a violation…to be proper they should terminate on its own double pole breaker within the panel…usually near the top…

Hope this helps

Thanks. I get the surge suppressor thing. I was glad to see I was on the right page with that. As far as the grounds and neutrals I am still a little grey. If there is only one panel what is the general rule? Most panels I see in this situation have the grounds and neutrals sharing bars. I am never sure if I should suggest separating them in this instance.If there are two buss bars and the grounds and neutrals are not separate, when is that ok?

Panel not clearly labeled-ground wires and nuetrals need to be on sepatare buss bars.JPG

Paul,

Ok…lets make this simple…

Commit to memory - Rule 1- If their is only (1) panel in the house and the only disconnection point…then the Neutral and Grounding conductors should terminate on terminal bars that are connected together…

Commit to Memory - Rule 2 - Panel’s OTHER than the one above will require (4) coductors from the main panel to the SUB panel…and in the sub panel the grounded ( neutral ) and the Grounding conductors should terminate on seperate terminal bars…and the one with the neutrals should be floating and not in contact with the enclosure…ie: isolated

Maybe better to explain on the phone…feel free to call me anything you are confused…

RED- General rule as YOU have requested ( not in assumed senerios )…is that the Grounded Conductor ( Neutral ) and the Grounding ( and Bonding in case you would like to know that was well ) should terminate on the same terminal buss…if they dont…they should and a bonding jumper must exist.

GREEN - Correct…this is normal

BLUE- No you should not suggest that…if the GREEN line is done…and it is the main disconnection location.( do not go into senerios guys )

ORANGE - sure…if it is the main panel as explained before and is not a sub-panel ( remote distribution panel )

Also…i will assume you have not done the online electrical course…i would suggest you do it as it will explain alot.

The neutral is the grounded conductor. The grounded conductor is allowed to be (and must be) grounded only at the service equipment. The service equipment is the first point past the drop or lateral, where the power can be disconnected from the building - whether it’s a single disconnect or multiple switches.

The grounded conductor is the return path for the ungrounded conductor. This is why it must return to the point of origination (the service). Any other point where the neutral is grounded, would create a potential for energized components (conduit, enclosures/boxes) because the current is still trying to return to the service equipment (its point of origination).

Grounding the neutral at any point other than at the service equipment, creates a potential for a parallel path of current. This parallel path is generally through grounded and/or bonded components that, under normal conditions, would not be energized, and may likely be exposed to human contact.

I’m sure it’s much more complex than that, but this is the most simple explanation I can give.

Thanks for all of the info. I appreciate everyones help.

BTW, Some Square D surge arrestors were recalled due to fire hazard http://www.cpsc.gov/CPSCPUB/PREREL/PRHTML95/95168.html