07:36AM | 12/16/02
Member Since: 10/08/02
30 lifetime posts
I just open my main service panel for the first time since it was installed 3 years ago to install a new circuit and breaker. I noticed that there was no separate ground bus and that the electrician who did the install put both the neutral and ground wires in the neutral bus for each circuit. The main ground wire is also connected to the neutral bus.

Is this OK? I thought all main panel boxes had separate buses. The box is made by Siemens. Type QP breakers. 200 amp.


03:30PM | 12/16/02
Member Since: 09/01/02
25 lifetime posts
Most panel equipment that is manufactured for the residential market has only one buss bar installed at the factory. If you look you will find that the factory installed buss bar is bonded to the panel cabinet when the panel is used as service equipment. The service equipment is the one place were the connection between the grounded current carrying conductor (that most of us call the neutral) and the enclosure is supposed to occur. Service equipment is also the place were the Equipment Grounding Conductors (EGCs) are connected to the utility's grounded conductor (neutral) via the grounded service entry conductor (neutral). When this type of panel is used as a feeder supplied panel instead of as service equipment then additional buss bars are added which bond through their mounting screws directly to the cabinet. The main bonding jumper screw or strap is then removed from the factory installed buss bar to leave it insulated from the equipment enclosure.

Some designs, such as GE, have a bridging bar that serves as the connection between the halfs of the buss bar located on each side of the panel. One side has the main bonding conductor installed in the form of a screw. As long as the bridging bar is in place then both sides of the buss bar are functioning as one buss and are bonded to the panel cabinet. If that panel is to be used as feeder supplied equipment rather than as service equipment the bridging bar is removed. The bar on the bonded side is used as the Equipment Grounding Conductor buss bar. The bar on the unbonded side is then used as the grounded conductor buss bar. The drawback to that design is that one of the conductors for each circuit has to be routed to the opposite side of the cabinet.

Other panel equipment is factory equipped with separate buss bars for the grounded current carrying conductors and the Equipment Grounding [actually bonding] Conductors (EGCs) in order to facilitate the panel being used as a feeder supplied panel rather than as the service equipment. Such panels are not commonly used in the residential market. When panels that are factory built for dual use are used as service equipment the two types of conductors may be on separate buss bars but they are connected to each other by the main bonding jumper that bonds the grounded current carrying conductor buss bar to the panel cabinet that is serving as the service equipment enclosure. When that same piece of equipment is used as a feeder supplied lighting and appliance or power panel board the only change that is needed is to remove the main bonding jumper.

Click to reply button
Inspiration banner


Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.

Reply choose button


Post new button or Login button

To test the boundaries of small-footprint living, interior designer Jessica Helgerson moved her family to a 540-square-foo... Filling an underutilized area beneath the stairs is a smart way to save space. Doing so with a stash of wood, however, is ... The Audubon Society inspired wallpaper in this Adirondack-styled mudroom will get you in the outdoor mood. Grab your coat ... Chalkboard paint opens up endless possibilities for customizing your dresser time and time again. Use chalk to label the c... A fireplace in the bathroom creates the ultimate setting for relaxation. Homeowners often choose electric or gas over wood... This roomy boot tray made from punched metal stands up to all the elements. Station it in your mudroom or at your back doo... There’s nothing like a new set of cabinet hardware to refresh a room. The possibilities are endless: Go modern, rustic, or... FLOR tiles are an affordable way to customize a carpeted floor covering for any space. Make anything from runners to wall-... Chalkboard paint features prominently in this elegant yet unpretentious headboard design. Add a new message daily to reflec... Salvaged boards in varying widths and colors make up the dramatic accent wall in this attic space. The high-gloss white of... The indecisive homeowner need not fret over choosing one (or even two) cabinet colors. The kitchen cabinets in this artist... Incorporate nature into your lighting scheme by securing a dead tree in a concrete mold and draping your pendant lamp from... Simple and striking, a couple of pieces of "lovingly used" furniture creates a special kind of charm. A weathered chair fo... First dress up your metal shelves with a coat of paint in an accent color that complements your kitchen decor. Then arrang... Dark wood shelving and a matching upholstered bench keep this closet sleek and refined. The large window brightens the sub...
Follow banner a
Newsletter icon Flipboard glossy Facebook Twitter Pinterest Youtube Rss icon