A standard 2 pole switch. [Linked Image]

A 400 watt fixture run at 240 will draw about 2 amps.

I would not put more than 5 of these on a 15 amp circuit or 6 on a 20 amp circuit.

If by chance you try a hot restart they will, many times draw higher amperage and will trip the breaker of a maxed out circuit.

Bob Badger
Construction & Maintenance Electrician
Massachusetts