Load Center Vs. Panelboard

Status
Not open for further replies.

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
yup....as far as the code is concerned. Manufactures although place a difference.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
Its kind of like asking the difference between a 4x4 and a pickup.

But traditionally some major differences are:
Loadcenters are designed to fit into 2x4 stud cavities while panelboards are usually deeper and wider.
Loadcenters have fewer available options, while panelboards can have just about anything you are willing to pay for.
Loadcenters usually have plug-in breakers only, while panelboards are typically ordered with bolt-on breakers.
 

darekelec

Senior Member
Location
nyc
Panelboard is 'the guts' of breaker box.
Load center is a trade name, like 1900 box.
But in the field means the same.
 

Attachments

  • panelboard.jpg
    panelboard.jpg
    13.2 KB · Views: 30

Smart $

Esteemed Member
Location
Ohio
Here's what Schneider says on...

What is the difference between QO load centers and NQ panelboards?

A QO load center is a panelboard. It is tested in accordance with UL67, the same as a NQ panelboard . Some of the functional differences may include:
NQ can be factory assembled to custom specifications. QO is merchandised only.
NQ enclosures are normally 20`` W x 5.75`` D and generally galvanized steel boxes . QO enclosures are normally 14.25``W x 3.75``D with grey painted boxes .
NQ enclosures are available in more NEMA types than QO, which is offered in NEMA 1 and NEMA 3R enclosures only.
NQ trims are monoflat with no exposed screws and a recessed handle/lock . QO trims show the mounting screws and use a raised door latch with optional lock .
NQ accepts plug-on and bolt-on breakers. QO accepts plug-on breakers only .

Lastly NQ panels are generally considered to be for commercial , institutional and industrial applications . The QO load center is primarily targeted for the residential , light commercial and light industrial marketplaces .
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
AFAIK,
Loadcenters never come with an EGC bus. Must be purchased separately.
Loadcenters always come with cover/deadfront, cabinet and panelboard in the box.


Square D loadcenters are most commonly shipped without the front 'in the box', except the ones sold at the big-box stores
If there is a "G" in the part number, that Square D loadcenter is shipped with a factory installed ground. I believe ground bars are standard in most of the QO line that are sold as main lugs only, as these are likely to be 'sub-panels'
 

Carultch

Senior Member
Location
Massachusetts
Being told these are exactly the same. is that true?

The difference is generally size, and application. These each perform approximately the same function, of distributing incoming currents to the branch breakers of outgoing circuits.

If you are looking for a generic term, you could call it a power distribution enclosure. I don't think anyone has proposed a generic term in the NEC.

To rank order the terms by size & complexity:
Load Center
Panelboard
Switchboard
Switchgear
Motor control center

Load Centers are generally 100A and less, maybe up to 200A. Usually used for single phase residential applications. Less options available to add to them, mainly bussing, breakers, and the enclosure. Usually built with the intent that components are purchased separately and constructed in the field. Usually mounted upright on or in a wall.

Panelboards are generally 100A thru 1200A, and are built for commercial applications, and major residential applications. More options available to add to them, and generally purchased as a complete factory assembled system, when you ask for it. Panelboard on its own only refers to the interior, with the enclosure coming separately. You can have the enclosure come with it, by ordering it as "panelboard complete". Panelboards are usually mounted upright on or in a wall, or strut structure.

Switchboards are built for large industrial applications, at utilization voltage. We are talking about a free standing piece of equipment, with cabinet sized breakers located throughout it. Often configured with built-in metering sections. And branch breakers are grouped in sections. Branch breakers may also be replaced with branch fused disconnects instead.

Switchgear is like a switchboard, except it also contains medium voltage. It could contain the transformer as well.

Motor control centers are similar to switchboards and switchgear, although they differ by application. It usually contains contactors for remote and automatic switching of the motors, in addition to breakers.
 

Carultch

Senior Member
Location
Massachusetts
Square D loadcenters are most commonly shipped without the front 'in the box', except the ones sold at the big-box stores
If there is a "G" in the part number, that Square D loadcenter is shipped with a factory installed ground. I believe ground bars are standard in most of the QO line that are sold as main lugs only, as these are likely to be 'sub-panels'

Interesting how they either come with or without a ground or neutral, based on your predicted application. Same with disconnects...the fused ones come with a standard neutral and the unfused ones come with no ground or neutral. I seldom see an application where you wouldn't need an EGC.

I'd rather just see everything come with a comprehensive neutral and ground. It is the easiest thing to forget to order.
 

kwired

Electron manager
Location
NE Nebraska
Square D loadcenters are most commonly shipped without the front 'in the box', except the ones sold at the big-box stores
If there is a "G" in the part number, that Square D loadcenter is shipped with a factory installed ground. I believe ground bars are standard in most of the QO line that are sold as main lugs only, as these are likely to be 'sub-panels'

I have found that main lug panels from supply house have an equipment grounding bar included, main breaker panels don't. But go to big box store and sometimes it is exactly opposite :( This is for both QO and Homeline panels, not so certain what they have for other brands.


My answer to OP which has kind of already been mentioned is loadcenters are sold as a packaged unit - sometimes with the need to select type of cover needed. They are still panelboards as far as NEC goes though. But the non - loadcenter panelboard is generally not a complete item, you customize what you want for every purchase, though there are some standards and limitations. You generally order panelboard(interior portion) then additional options - main lug/main breaker, sub feed lugs, maybe even sub feed breakers that are connected to the end of the bus instead of along the bus, you then order a cabinet with size based on what panelboard and options are to be included and you typically have some choices for covers. NEMA 3R, 5, 12, cabinets may not give you much for cover choices.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
QO stands for Quick Open.

I couldn't find anything on NQ.

The QO line was available for several years before the Qwik-Open feature appeared in advertizing. The QO replaced previous breaker and loadcenter types MO and XO. Qwik-Open is only on 15 and 20A 1pole breakers.
At the time of introduction, in the late 50's, the full product line included the QO, Q1, Q2, and Q4 types of breakers. QOB and Q1B were bolt-on equivalents
"Q" was, and still is Square D's prefix for 240Vmax breakers.

This brings us to the NQ panel board. "N" is Square D's prefix for panels that are usually used as 'Lighting and Branch Circuit' as opposed to loadcenters. Historically the N prefix was paired with the breaker prefix to create the panelboard type. This was a good marketing idea, but it eventually fell apart as panel and breaker types kept changing and evolving.
So, an NQ panel, is a 240V panelboard that accepts QO breakers. Previous versions were the NQOD (which accepted both plug-on and bolt-on breakers) and the NQO and NQOB (which accepted only plug-on or bolt-on respectively).
 
Status
Not open for further replies.
Top