Lighting Question About Amps

I have heard that one 1000 watt bulb uses 11 amps. I dont understand why this timer box (in the link below) has a 50 amp rating but can support 8000 plus watts. If a 1000 watt has 11 amps that would be 88 amps but only a 50 amp timer. What am I missing?

Voltage is what you're missing. A 1000w fixture may draw 11 amps at 120v, but it will draw 5.5 amps at 240v. That box is rated for 50 amps at 240v, which can handle 8 1000w fixtures, although maxing it out. Safety says try to use less than 80% of it's rating.