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A load center is theelectric service panelthat distributes electricity throughout the house.
What Is a Load Center?
Each circuit is protected with acircuit breaker.
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The National Electrical Code (NEC) does not distinguish between a load center and a panelboard.
This punch in of panelboard is rarely found in homes.
What Is a Lug?
A lug is a copper or aluminum connecting terminal that clamps down the bare end of an electrical wire.
The load center distributes the power to the home’s branch circuits.
Every home with electrical service will have a main breaker load center.
A lever-stylemain breakerprovides overcurrent protection to all downstream branch circuits.
A main breaker operates much like the smaller circuit breakers that are found in the panel.
A main lug load center is sometimes installed to expand the number of circuits in a home.
In addition, it creates independent electrical zonesespecially valuable when building anaccessory dwelling unit or ADU.
Not all homes have a main lug load center.
Tip
Main lug load centers are sometimes called main lug only (MLO) panels.
The “only” emphasizes that these panels have only a main lug, not a main breaker.
A main lug load center has no main breaker.
Incoming power from the main breaker load center feeds into a central lug.
This lug feeds into the line side of the lugs attached directly to the bus bar.
Main overcurrent protection is provided by the main breaker load center’s main breaker.
Circuits in the MLO also have their own individual overcurrent protection with the circuit breakers.
A load center and a breaker panel are electric distribution centers that contain circuit breakers.
Load centers may or may not have main breakers.
A main breaker load center has a main breaker.
A main lug load center, or subpanel, does not have a main breaker.
A subpanel does not increase a home’s amps.
A subpanel is limited to thehome’s overall amperagesupplied by the main breaker load panel.
