well, a bulb and lamp are basically the same thing. technically, lamp is the correct term, but everyone calls them bulbs. so, I'm not sure what you have that's 1000 or 1500 watts or whatever. as long as you have a 600w ballast and a 600w lamp, you're good to go. maybe you have a 15amp circuit, which is pretty standard, and that would ballpark at 1500watts max draw. the circuit is basically the plug or plugs connected to a single circuit breaker. so, if you have two plugs connected to one circuit breaker, and you have your 600w plugged into one, you can't plug more than 900w into the other. hope that helps.