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What do Americans mean by 'single phase'?

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Muzzerboy:
A ground fault detector (GFI or GFCI in N America or RCD in Europe) checks to see if the sum of the L and N currents is zero. It should be zero - if it isn't, it means that some current is finding an alternative path from L (or N) back to ground. So yes, if you connect a bulb from live to ground, this will be testing that the GFCI / RCD is working ok. Modern "split circuit" consumer units have 2 separately protected circuits so you can connect the lights to one and your loads to another. Then, when you trip a power circuit you aren't left in the dark. Very clever.

If you connect a load from L to N, this should not trip the circuit. However, this won't do a whole lot to create a third phase. The only reason for fitting a capacitor like that would be to adjust (improve) the power factor when you have a large inductive load. It doesn't help the load to work better but it can mean you don't pay so much for your power. I'm not sure the guy really knew what he was doing but as I said, I couldn't be arsed to watch the whole thing.

ddmckee54:
Muzzerboy:

He was probably using the capacitor to help shift the phase on that leg of the circuit.  I don't know how much it would shift it, it's been WAY too many years since I did any calculations like that, makes my head hurt just thinking about it.

I did something similar about 25-30 years ago to test a PLC interface for some 3 phase power monitoring equipment when I only had single phase available in the shop.  I used the inductance of a 1000' spool of wire to shift the signal to the monitoring equipment.

Don

DavidA:
The bit about connecting a capacitor from a phase to ground/neutral was towards the end of the video.

Anyway, any current leakage from either the lighting or the power circuits trips my whole system. So I probably won't be trying that.

Dave.

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