The PTC series of Day/Night Controllers by Custom Automated Products
are perfect when you need to turn a device on only during daylight
hours or only at night. A photocell senses whether it is day or night,
and turns the device plugged into it on or off depending on which model
you are using. The PTC-1 turns on whatever is plugged into it during
the day when the lights are on. The PTC-2 turns on the device during
the night, when the lights are off. PTC controllers are rated for 15
amps @ 120 volts. 3 year warranty.