Expert: J Cook - 11/6/2009

Question
Hi Mr Cook

I am installing Recess lighting in our basement, I have a ceiling with a foot and half space with no insulation above so I just need to cut the hole. Which I have no problem doing. My worry though is the electric. I have a light already which I am going to replace with a recess light. Can I use that existing light once changed out and then pass the eclectic wire on so it is just one wire? How can I tell how many canister I can install using that same method with out blowing a breaker or a fire? What kind of electric wire can I use? I think I understand how to do this, I just would like and expert option.   Thank you for the help and time

Answer
You can " Daisy Chain " from light to light. The calculation to determine how many on one circuit is: Watts divided by volts = Amps

So, 10 100 watt lights = 1000 watts divided by 120 volts = 8.33 amps, so these 10 lights can be installed on a 15 amp circuit. The wire size is determined by the existing circuit breaker. If this is a 15 amp circuit, #14 can be used, if it is a 20 amp, #12 must be used. Thanks