I have a new Square D load center installed rated at 100 amps.
What does the 100 amp rating mean? If I replace the 100 amp main breaker with 200 amp breaker does that mean that
The load center could melt if 200 amps flowed through it or that the incoming service wires could melt or what.

Just what could happen if the rated current capacity of the load center is exceeded.

Yes and yes. If the main breaker is 100A, then the service conductors are should be sized accordingly.

I think I know the answer to this but, what is the difference between a 100 amp box and a 200 amp box with
No external circuits connected to it? I'm talking about just the guts of the boxes

Thanks for the previous answer.

A 100A main breaker panel is deemed such by the manufacturer according to metal bus bar sizes, main lug terminal sizes, and the ampacity of the panel. The manufacturer has fail tested each panel, and this is how it is determined. The bottom line is a 100A panel will overheat if you attempt to run 200A through it. Please stick with the ratings on our panels, and do not attempt to modify them this can be extremely dangerous.:eek:
WE HOPE THIS HELPS!
TOMMIES SCHNAKIES:cool:

First, just changing the panel breaker without having the Power Company change the transformer taps to allow for the increased current will not increase your amperage.

If your goal is to go to 200 amps, you must start with the Power Company.

If you just change out the breakers, you have just disabled the ability of the circuit breakers to protect you from fire. The reason is that the 200 amp breakers will not react to amperage below 200 + amps.

If for some unknown reason you start pulling 150 amps through a 100 amp conductor, the heat can cause the insulation to melt. Then bare wire can arc to anything flammable and good bye home.

Do not do this. Please see a licensed electrician before you try anything. Remember, if you try to change out the panel protectors, you will be working on Live wires with charges that can easily kill you!

To continue from above--You are to contact your local power company to set up their inspection. If they approve of the work it is the power company's responsibility to permanently splice the overhead service at the POA. They will make the determination as far as if their over head triplex is acceptable to meet your demands, after all it's the power Co. property

Tommy,

What is the point of pulling permits, getting inspections and then calling the Power Company.

Would it not be smarter to start with the Power Company to make sure they are willing to increase the amperage?

Just curious, but can you tell me where in the NEC I can find the NEC's authority over a Power Company. Here when we want a supply upgraded we have to show the AHJ that we have the Power Company's agreement. It's part of the crayon plan submission.

Just curious, but can you tell me where in the NEC I can find the NEC's authority over a Power Company.
The power company does not follow the NEC. They all make, and follow, their own rules.
The NEC (or whatever codes is in place) begins at the service point.

NEC
90.2 Scope

(B) Not Covered This Code does not cover the following:

(4) Installations of communications equipment under the exclusive control of communications utilities located outdoors or in building spaces used exclusively for such installations

(5) Installations under the exclusive control of an electric utility where such installations

a. Consist of service drops or service laterals, and associated metering, or

b. Are located in legally established easements, rights-of-way, or by other agreements either designated by or recognized by public service commissions, utility commissions, or other regulatory agencies having jurisdiction for such installations, or

c. Are on property owned or leased by the electric utility for the purpose of communications, metering, generation, control, transformation, transmission, or distribution of electric energy.

FPN to (4) and (5): Examples of utilities may include those entities that are typically designated or recognized by governmental law or regulation by public service/utility commissions and that install, operate, and maintain electric supply (such as generation, transmission, or distribution systems) or communication systems (such as telephone, CATV, Internet, satellite, or data services). Utilities may be subject to compliance with codes and standards covering their regulated activities as adopted under governmental law or regulation. Additional information can be found through consultation with the appropriate governmental bodies, such as state regulatory commissions, Federal Energy Regulatory Commission, and Federal Communications Commission.

Just curious, but can you tell me where in the NEC I can find the NEC's authority over a Power Company. Stan answered this.


Here when we want a supply upgraded we have to show the AHJ that we have the Power Company's agreement. It's part of the crayon plan submission. Good Electrical Contractors will consult with the serving utility--rather manual, or engineer--before starting a project.
Don,
I believe the way your area is going about things is perfectly fine. Each serving utility will have a different set of rules, and the only way you will know this, is by consulting (Rather manual, or engineer) with them first.

Don,
If you require a large service to your building, the power co. will do everything in their power, no pun intended, to provide adequate size wiring to it. They love to sell power, it's what they do.

Thommyschnak, I had the pleasure of being in the City Inspectors office today. It seems that their process was changed about 15 years ago. The current process has you obtaining the permit, doing the work, and getting the inspection. Once the work is approved, they turn it over to the Power Company.

The other process I described was used because neither the inspectors or the utility company could keep up with the demands on the power company. When demand backed off, the current process was restored.

Gee, leave a place for 25 years and everything goes to rack and ruin.

The current process has you obtaining the permit, doing the work, and getting the inspection. Once the work is approvedPretty much normal depending on the install! Let me say this: Any contractor who pulls a permit for service work-without consulting with the serving utlilty (rather manual or engineer) specifications-don't deserve to be in business!!