Interlock Kit
A sliding plate on the panel cover that physically prevents the main breaker and the generator backfeed breaker from being on at the same time: the budget alternative to a transfer switch.
The interlock is elegant in its simplicity: one piece of metal that lets you close the generator breaker only after the main is off, and vice versa. Combined with an inlet box, it turns the whole panel into a manual transfer system: during an outage you flip the main off, slide the plate, energize the generator breaker, and manage your own loads by switching breakers.
Two requirements keep it legitimate: the kit must be listed for your exact panel model (generic plates fail inspection), and the install should be permitted like any service work. The trade-off versus a transfer switch is load discipline: nothing stops you from overloading the generator except your own breaker management.
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- Standby Generator : A permanently installed generator (Generac, Kohler, Briggs) that starts itself within seconds of an outage, runs on natural gas or propane, and feeds the house through an automatic transfer switch.
- Inverter Generator : A generator that produces clean, electronics-safe power by converting its raw output through an inverter, throttling its engine to match the load.
- Load Shedding (Load Management) : Automatically dropping or delaying big loads (AC, water heater, EV charger) so a smaller generator, or a smaller electrical service, can handle a home that would otherwise overload it.
- Home Battery Backup : Wall-mounted battery systems (Tesla Powerwall, Enphase, FranklinWH) that back up the home instantly and silently, recharged by solar or the grid: the generator alternative with no fuel and no noise.