Category
Transfer Switches
The bridge between utility power and your generator. Automatic transfer switches (ATS) sense an outage and cut over in seconds — manual switches let you control which circuits run during a planned outage.
Automatic
ATS
Required for whole-home standby generators. Senses utility loss, starts the generator, transfers load in ~10 seconds.
Manual
Manual Transfer
Cheaper option for portable generators — flip individual circuits between utility and generator power during an outage.
Sizing
Amperage Guide
Match or exceed your main breaker. 100A panel → 100A switch. 200A service → 200A. Whole-home commercial: 400A+ service-entrance rated.