pot lights

[Ampacity]

When installing pot lights rated at 150 watts using 90 watt lamps is the circuit load calculated on the lamp being used or the actual rating of the fixture? Also these pots will be controlled by 2400 watt dimmers with 20 amp. circuit breakers and #12 wire. Can the dimmer be loaded up to the full 2400 watts? Thanks in advance Ampacity

[rmurphy]

As I read it your calculated load could be calculated with the 90 watt bulbs. The only problem is that when you leave what is stopping the owner from changing the bulbs. A couple of other things to keep in mind are that altough your dimmer is rated at 20 amps(120 volt supply) Unless you have a 100% panel your 20 amp breaker is only rated for 16 amps. Which in turn drops your dimmer to 1920 watts. If your getting close to your allowable load it's always a good idea to add a circuit. Add ons and changes always seem to happen. One more thing to keep in mind is that higher wattage dimmers often have a heat sink on the front which work best in single gang boxes. Good Luck!

[Ampacity]

The local inspector said that if I label each fixture as to the maxomum wattage we are installing that would be acceptable. In this case it's a 90 watt lamp in a fixture rated at 150 watts.