What is a typical rating for a residential electrical service?

The typical rating for a residential electrical service is indeed 120/240 single-phase 3-wire. This configuration is standard in most homes and provides the versatility to power typical household appliances, lighting, and other electrical devices effectively.

In a 120/240 volt service, the voltage is split between two hot wires, with one wire carrying 120 volts and the other carrying 240 volts. This setup allows for the use of 120 volt circuits for standard convenience outlets and lights while also providing 240 volts for larger appliances such as dryers, ovens, and HVAC systems. The three-wire system involves two hot wires and a ground, making it safe and efficient for residential usage.

While other configurations may exist, such as three-phase systems or different voltage arrangements, they are not commonly used in standard residential services. Three-phase systems (like 240/480) are typically found in commercial or industrial settings where higher power is needed. The 120/220 configuration is less common and does not provide the same standard level of service. The 240/120 single-phase 4-wire system, often used in larger applications or specific types of equipment, is more suited to specific cases rather than general residential use.