Clodbuster
Member
- Location
- Eastern Washington
Had an interesting thing happen. Am finishing up rewiring a farmhouse, 1950s construction with a 1967 remodel. Have been slowly pulling new grounded NM-B to each device to replace old 2-wire stuff. There's a nice kitchen range hood with a light. I pulled new wire through, landed the brand new ground and made the connections. Turned on the breaker and walked back upstairs to test it. Fans worked fine, turned on the hood light, it worked for about a second and a half and then ZAP!
It didn't make sense - I hadn't touched the light/switch part of the range hood where it arced at all! So pulled it apart to see and this is what I found: During the original install or even the factory assembly, over 50 years ago now, one of the wires from the ballast got pinched between some sheet metal. Evidently not enough to fail completely, but enough to sit there, almost or maybe slightly energizing an isolated metal hood for half a century.
Until a return path was created, and then it was all over in less than two seconds.
So now I wonder - who made the ground fault, me or him?
It didn't make sense - I hadn't touched the light/switch part of the range hood where it arced at all! So pulled it apart to see and this is what I found: During the original install or even the factory assembly, over 50 years ago now, one of the wires from the ballast got pinched between some sheet metal. Evidently not enough to fail completely, but enough to sit there, almost or maybe slightly energizing an isolated metal hood for half a century.
Until a return path was created, and then it was all over in less than two seconds.
So now I wonder - who made the ground fault, me or him?
