What Is a Generator Interlock?
A generator interlock is a panel-mounted device that coordinates the utility main breaker and a standby generator breaker. The interlock allows only one power source to feed selected circuits at a time. This arrangement directs generator power through the home’s electrical panel while preventing simultaneous utility and generator connection.
Quick Facts About Generator Interlock
Category
Generator transfer equipment
Used for
Manual generator connections
Common confusion
Not an automatic transfer switch
Also called
Interlock Kit, Generator Interlock Kit
Often discussed with
Generator Installation
Key Takeaways About Generator Interlock
- The device coordinates utility and generator breakers.
- It works with a compatible generator inlet and panel.
- An interlock is not an automatic transfer switch.
How Generator Interlock Works
A generator interlock mounts to a compatible electrical panel and controls the position of the utility main breaker and generator breaker. Its sliding or pivoting mechanism permits one breaker to remain on while the other stays off. The panel then receives power from the selected source through the generator inlet.
Related glossary terms: Generator Inlet, Automatic Transfer Switch, Electrical Grounding.
During an outage, the utility breaker is placed in the off position before the generator breaker is engaged. The generator feeds connected panel circuits through the inlet and branch wiring. When utility service returns, the generator breaker is disengaged before normal power is restored. A generator inlet provides the connection point outside the panel, while the interlock controls source selection inside the panel.
From the GMB Electric team
When we install or inspect a generator interlock, we check panel compatibility, breaker alignment, inlet wiring, and the condition of the grounding and neutral connections. We also verify that the interlock moves correctly and that the labeled operating sequence matches the equipment installed.
Generator Interlock in Practice: A Real-World Example
A homeowner has a portable generator and wants to power selected household circuits during an outage. A generator interlock at the electrical panel works with an exterior generator inlet, allowing the homeowner to select generator power through the panel without connecting the generator directly to individual circuits.
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Have Questions About Generator Interlock?
Contact GMB Electric for practical guidance on Generator Interlock and related 24 hour electrician work in Indianapolis.