x10 (PLW01-i) Switchs blow like a fuse.

[JohnnyHolt]

x10 (PLW01-i) blows when I turn on the light with it.  Replace it, it blew, and still again.  I had the one swith for years.  4 years on this outside light on the power pole.  The bulb is a 300watt.  That's the only thing on this switch.  Since it's an outside light, do you think it's a short between the switch and the light.  I know they are only rated at 500w so I keep way below that.  Been fine for this light for about 4 years.
Ideas, suggestions.

Thanks
John

[Dan Lawrence]

That isn't on the pole that your electric feeder comes from?   There may be leakage that's fouling your PLW01-i s  if it is.  I would never use anything X10 on a pole where my electric feeder is also on it.

[Brian H]

It is a possibility. There is a short between the switch's location and the light.
Since it is outdoors. You may also want to verify the light fixture itself doesn't have a failure in it.

[dave w]

Since it's an outside light, do you think it's a short between the switch and the light. 

Yup. You got "a short in the socket" so to speak.

If you are handy with a soldering iron you can probably repair the two blown units by replacing the triac. Radio Shark used to carry a 5A, 600V, pin compatible replacement.

[JohnnyHolt]

Thanks for your input.
I put a regular switch on there just to try it.  Trips the circuit breaker in the box instantly. Yep, got a short.
I'll have an electricion find the short.  Try replacing the triac myself just for the experience but put a new PLW01-i on there anyway.