Can a generator interlock work with every electrical panel?

A generator interlock works only with compatible panel designs and breaker arrangements. The panel manufacturer, breaker layout, enclosure condition, and available connection point determine compatibility.

Does a generator interlock start a generator automatically?

A generator interlock does not start a generator automatically. The operator starts the portable generator and changes the panel breakers manually according to the installed equipment.

What part connects a portable generator to an interlocked panel?

A generator inlet connects the portable generator cord to the building wiring. The inlet must match the generator connection and the panel equipment installed for backup power.

Glossary

What Is a Generator Interlock?

Generator interlock is a mechanical device installed at an electrical panel to control the position of the main breaker and generator breaker. The interlock permits only one power source to feed the panel at a time. This arrangement helps prevent utility power and generator power from connecting to the panel together during generator operation.

Quick Facts About Generator interlock

Key Takeaways About Generator interlock

A sliding or hinged mechanism links two panel breakers.
The device supports manual generator connection through an inlet.
An interlock is not an automatic transfer switch.

How Generator interlock Works

Two men stand by an open electrical panel, one gesturing while speaking to the other in a hallway

A Generator interlock mounts on or beside a compatible electrical panel and links the main breaker with the generator breaker. The mechanism allows the generator breaker to move only when the main breaker is off. Moving the main breaker back on prevents the generator breaker from operating.

Related glossary terms: Automatic transfer switch, Backfeed, Main breaker.

A generator inlet connects the portable generator to the panel through a suitable cord and wiring arrangement. The panel then distributes generator power to selected circuits, depending on the panel design and the generator capacity. A manual transfer switch performs a similar source-selection function through a separate switching device. An automatic transfer switch senses a power loss and changes sources without manual breaker operation.

A hand flips a generator interlock switch on a gray electrical panel indoors

From the Center Electric Service team

When we handle Generator Repair work, we inspect the interlock fit, breaker movement, panel compatibility, and inlet connections. We also check that the operating sequence keeps the utility source and generator source separated. Our team documents damaged hardware or altered panel parts before recommending a repair.

Generator interlock in Practice: A Real-World Example

A Riverside homeowner has a portable generator and a panel-mounted inlet. During an outage, the homeowner turns off the main breaker, moves the interlock, and turns on the generator breaker to supply selected household circuits.