Friday, I went to visit my friend, Charles Murry, in Moorpark who I met on the Air Raid Sirens forums

I missed his 12 noon siren test yesterday due to traffic (got there at around 1:00pm instead) and he had to leave for an appointment shortly afterward but I stayed there with his wife and her friends picking avocados and oranges from the orchard.

Anyway, I'm posting this here because the ranch was the site of the (in)famous "Air Raid Sirens forum CFL fire" which got spread around the Internet. The lamp in question which exploded in flames was a Lights Of America 23 watt Mini Soft White spiral.








Anyway, after getting back to the barn when we were done picking the fruits, I asked  his wife about the light which burned up and she pointed me to the end of the barn where it happened. The fixture that was damaged in the fire had since been replaced but I was told there were several of the same fixtures inside the barn.





Could anyone guess what may have been done ?

I feel that the bulb which caught fire had accidentally been powered with a 100 watt Mercury Vapor ballast. 

This is what replaced the burned fixture outside the barn door.




These are from the facts I got from his wife. If I can get a hold of Charles when he isn't busy, I'll try to verify the type of fixture.

That might be a cause. The ballast get more then twice the rated voltage (MV ballast OCV is in range 220..350V, depend on the exact type). As the current from the MV ballast is limited, it did not trip the fuse, but keep dissipating excessive power in the CFL ballast...

By the way i've seen CFL's offered as retrofit for MV. I don't know, if these use their own ballast (designed for the 200..350V input) or simply (preheater) fluorescents made to match MV characeristics (mainly rated operating current).

Kinda sucks if the lamp is getting the blame for the fire, yet it was installed in a fixture designed for a MV lamp. 

Kinda sucks if the lamp is getting the blame for the fire, yet it was installed in a fixture designed for a MV lamp. 

I agree strongly! I'm sure if the lamp was run on 120, instead of the MV ballast, it would still be going! but this is kinda scary! 

It is amazing the abuse some of these CFLs have taken.  I've seen them run on MV ballasts like this, CFL ballasts for non-self-ballasted LOA Fluorex fixtures, and even HPS ballasts with the igniter connected