I attached a dusk to dawn photocell to an existing light fixture.
The fixture uses a 75 watt bulb, but the photocell adapter says it works up to a 150 watt bulb. Which
wattage do I need to abide by?
If the light fixture has a limitation of 75 watts, then that's the largest bulb
you can use. Otherwise, it would be the smaller of the photocell adapter, or the rated maximum wattage allowed for use in
I have a 50 watt metal halide light
fixture that is putting out 302vac at the socket. What could cause that?
That's what they're supposed to do. The ballast of a high-pressure lamp (and also
many fluorescent lamps) will supply a higher voltage than the input voltage to enable the lamp to strike.