![]() ![]() ![]() One old house that had its wiring fixed by a friend had a two wire (live and neutral but no earth) system where the wires were let into grooves in wooden conduits. ![]() They probably are but people still use them. IMHO those voltage operated GFCIs that date from the 1950s and 1960s ought to be banned. Result no more electric shocks! I did that "bodge" about thirty years ago and its still working fine. After checking all the legal stuff it was decided to use PME (Protective Multiple Earthing) A heavy duty wire link was connected between the Neutral and the Protective Conductor (AKA "Earth") on the fuse-board where the power entered the building. Power was supplied from a pole-transformer dropping the 11,000 volts to 240 and with these the neutral is always earthed at the pole. Water taps, light switches, the kitchen range and anything metal that was supposed to be earthed were all live! The property was owned by a penniless widow and there was no money to do the job properly. I suspected that the immersion heater element had also corroded and was now pumping current into the hot water system. The floors were concrete and the bungalow had a voltage operated GFCI with a blown coil. One delightful property that I was asked to "look at" was giving everyone electric shocks. This leaves everything in the house un-earthed and with no GFCI. The problem with this type of GFCI is that electrical storms can blow the trip coil. If anything in the house leaks current the GFCI will turn off the power. The other end of the trip coil connects to the earth rod. The house earth wires connect to one end of the trip-coil of the GFCI. If the currents are not equal the transformer produces voltage which operates the trip relay and cuts off the power. Normally the go and return currents are equal so the transformer does nothing. The modern type contain a little toroidal transformer that the live and neutral are threaded through. I suspect that some writers are confusing the old Voltage Operated GFCIs with the new Current Operated GFCIs. You'll then be able to use the load side of each receptacle to feed other devices, like this. So you should be able to do something like this. The catch is you'll have to pigtail the neutral to the receptacles, not use the neutral from the load side of the first GFCI to feed the second. You can share a neutral between 2 GFCI receptacles. You'll install the GFCI's as the first receptacle on each circuit, which will protect all downstream receptacles. Then install 2 20Amp breakers, to supply the kitchen. To wire up the kitchen properly, you'll have to pull 2 new 12/2 cables from the breaker to the kitchen (all #14 wire on that circuit will have to be replaced). GFCI receptacles work by monitoring the balance between hot and neutral, so if the neutral is shared the GFCI will not work properly. GFCI receptacles will not work properly with a shared neutral, you'll end up with nuisance tripping with a shared neutral. You'll have to pull new wire anyway, if you want to hook up GFCI receptacles. NEC calls for 2 20Amp small appliance circuits in the kitchen, to accomplish this you'll need to switch to 20Amp breakers and #12 wire. The first problem is that you may be using the wrong cable and breakers. ![]()
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