Quote:
Originally Posted by nealtw
the gfi plug trips when you short power to ground so you don't get a shock,
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Not all true. A GFI trips when it senses an imbalance in current between the hot and neutral. If there is an imbalance it assumes the current is going through a person and trips. This is how we get false trips or trips from wet appliances, etc.
A GFI does NOT trip under fault current (short to ground) situations.
Quote:
Originally Posted by nealtw
A house wired in the fifties should have ground wired to the box have another look!!
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Not at all a certainty. Many homes I see from this era are wired with old ungrounded NM cable or old BX without the bonding strip which CANNOT be used for grounding purposes.
The ONLY way to be sure is to visually check.
Quote:
Originally Posted by nealtw
If the vent pipe is cast iron or copper it will be a good ground..........
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Completely false and potentially unsafe!
There are very specific rules to using a water pipe for a grounding source, and the attic is NOT one of them. In fact, 99.9% of the time it is as easy or easier to run a wire back to the panel.
Neal, I must ask. What is your profession?