Five years ago, I had an electrician installed a dimmer switch that
controls 8 flood lights in the finished basement. A couple hours ago,
when I tried to turn off the dimmer switch, the button got stuck and I
could not switch it off. When I tried to turn it off, I found a little
smoke coming off from the switch. As mentioned above, I could not turn
off the switch; I had to turn it off by turning off the breaker in the
main panel.

According to past posts, the smoky situation means that the dimmer
switch may be overloaded. But I cannot see why it is overloaded. The
Skylarks dimmer from Lutron is rated as 1000W, and the total load of
those 8 flood lights is only 520W that is only slightly more than 50%
of the rating of the dimmer switch (each flood light is rated as 65W
and 130V). Why did the dimmer switch become overloaded?

Based on my past review of all the circuits in my house, that dimmer
switch circuit should only support those 8 flood lights and nothing
else.

I cannot upgrade the dimmer switch because 1000W is the highest that I
can get according to Lutron web site:
http://www.lutron.com/skylark/?s=17000&t=17200
This means I will have to stick with 1000W dimmer switch. What should
I do to prevent this problem from coming back?

Thanks in advance for any info.

Jay Chan