ECN Forum Forums Photo Discussion Forums Photos for General Discussion Trade Practice - Why 'Flip' the Recep?

ESC, Replacing a two prong receptacle on a two wire circuit with a GFCI device is an acceptable method and the device will trip.

Heres part of an articel from ECMweb.

Let’s talk about the last two options. A GFCI-protected grounding-type receptacle without an equipment-grounding conductor is safer than a grounding-type receptacle with an equipment-grounding conductor, but without GFCI protection. This is because the GFCI protection device will clear a ground-fault when the fault current is 5mA (+ or - 1mA), which is less than the current level necessary to cause serious electric shock or electrocution.

ESC, GFCI devices do not, I repeat: do not require an EGC to operate. I take your comment to mean that a plug-in GFCI tester will not trip the GFCI receptacle. That is true.

A GFCI operates by detecting a difference in current between the hot and the neutral, which indicates that much current is getting back to the neutral by some other pathway.

A GFCI's internal test button allows 5 ma. to flow between the circuit's hot (after the current sensor) and the neutral (ahead of the current sensor). (120v / 0.005a = 24K Ohms)

The reason a GFCI's test button works, and a plug-in tester's test button does not, is that the receptacle has access to the neutral ahead of the differential-current sensor, and the plug-in tester does not.

Therefore, the only way the plug-in tester can place a low-current pathway between hot and earth is through the grounding pin. If it used the neutral, the GFCI wouldn't detect any difference.

We sometimes flip the grounds up for the office workers who are always dropping paper clips ontop of a loaded recept , and sometimes flip them at the fast food joints that use those foil burger wrappers.

Larry and Lone,
I stand corrected. Thanks for setting me straight.

Anyone ever put a single pole switch in the No and FFO Position?

I used to work on airplanes and I swear to god we would get pilots (this is IFF Gear) that would send us gripes that said, "Will not function in the OFF position.