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Transfer Switch Planner

Choose the circuits you want backed up and see the switch type, circuit count and inlet amperage to ask an electrician for.

Recommended solutionManual transfer switch, 6 circuits
Circuits selected4
Switch spaces needed4
Backed-up load2,800 W
Inlet to specify30 A / 240 V

A pre-wired manual transfer switch covers this list cleanly and is the least expensive code-compliant option. Pick the circuits carefully: changing them later means calling the electrician back.

Which circuits do you want backed up?

15 A · 120 V800 W
20 A · 120 V700 W
20 A · 120 V500 W
20 A · 120 V900 W
30 A · 240 V1,500 W
20 A · 120 V1,200 W
15 A · 120 V400 W
15 A · 120 V300 W
20 A · 120 V400 W
20 A · 120 V875 W
15 A · 120 V400 W
15 A · 120 V400 W
20 A · 120 V1,150 W
20 A · 240 V1,200 W
30 A · 240 V3,000 W
50 A · 240 V5,000 W
30 A · 240 V5,400 W
30 A · 240 V4,500 W

How this is calculated

Circuit counts follow how transfer switches are actually sold: a 240 volt circuit occupies two spaces, so a well pump and a range together fill four of the ten spaces on a common switch. Pre-wired manual switches top out around ten to twelve spaces, which is why a longer list points to an interlock kit instead. The inlet amperage is the generator output divided by the working voltage, rounded up to the next standard inlet.

This is a planning aid for the conversation with an electrician, not a design. Transfer equipment must be listed for your panel, permitted and inspected, and neutral bonding has to be resolved for your specific generator.