Electric service is the supply component of electrical power to a building or residence. Electric service also has a delivery component, which consists of the transportation of electricity to the customer’s premises and metering. The customer may buy the delivery component of electric service from their electric utility company, or they may select a competitive supplier to provide the supply component.
Most residential homes have 120 volt electric service. This voltage is sufficient for most light fixtures, outlets, and small appliances. Some customers want to add more appliances such as electric stoves, which requires 220 volt service. In this scenario, a homeowner will need to upgrade their home’s electrical service.
When determining an existing home’s electric service size, the capacity of the circuit breakers in the panel is important. These are the devices that protect the wires from overheating. They have the ability to trip (cut off the flow of current) when the load exceeds a safe limit. Unlike fuses, which can blow, the circuit breakers will reset themselves after a trip.
Check the main breaker in the panel to determine its capacity. The main breaker is typically labelled with a number that indicates its capacity. It may be found on a label affixed to the power meter or it may be located inside the panel itself.
During the inspection, the inspector should inspect the power meter and panel for proper clearances, as well as the lateral service conductors. If the customer has a multi-family dwelling unit (duplex or triplex), the inspector should examine each of the apartments’ panels and disconnects to ensure that they have the correct capacity for the occupants’ electric loads.