Well here in the states you can't run a wire single it has to run in the wire conduit or same railway of the rest of the wires. Reason for that is if someone cuts the wire you lose your ground. Grounding to flex conduit is pointless because it flexes. so it's a bad connection all around. Wish I had a whiteboard to draw you a diagram & reason why you don't want to bond to like a water pipe. I'll try...
[Outlet]====Green wire=======|======Water Pipe===========|==========Earth Soil==============|========ROD========[Panel]
As you can see there is a very poor connection from the water pipe to the rod & nothing but dirt. In a electrical shock scenario this would never trip the breaker and if it did the person being shocked would be dead long before that ever happens. Just wanted to make that clear. That is the reason to make sure you have a copper wire all the way to a panels grounding bus bar. That way the breaker heats and trips. So what do you do with old worn out two prong outlets? Replace them with a 3 prong ground fault interrupters. Even though they are not Earth grounded they will still give protection as the circuitry in them will trip the breaker at the outlet. You can double this protection placing GFI's in the panel as well. Any power strip plugged into a GFI will also give protection to those. There is also a type called a Arc GFI and it senses electrical arcs in the wires in the home and will trip. This is good with older homes with poor wring mix of aluminum and copper wiring. Copper twisted to aluminum creates a galvanic reaction and causes corrosion thus leading to poor connection sparks and fire. Aluminum must be pressure crimped to copper never twisted and then covered with die electric grease once it's crimped. A earth ground doesn't really protect from a person being shocked all that well. Sure the panel breaker will heat up eventually, but not as fast as you would think. A GFI will instantly trip.
There is a caveat to GFI though. GFI must be tested all the time so you know the circuit in them are good and still functioning properly. They can still work and give full load but, the electronic tripping mechanism can be faulty inside it. Here in the states things are more regulated. Going all GFI in the home is a best, but it comes with a price tag at 20-30 dollars a piece. They are really good to have with children as they like to poke things into them. Some of them GFI even have a safety lock out shield if nothing is plugged into it.
Now with your problem I just wanted to know how much you have on the circuit. 100volts X 15 amps is 1500 watts. A oil heater on full power can draw that itself. A computer can be 60 or higher. Lights another 60. So if you got a lot on the circuit it adds up fast. Here in the US the outlets are 15 amp breaker @115-126VAC. So 120 x 15 = 1800 watts. A oil heater drawing 1500 plus a light and computer would be somewhere in the neighborhood 1620 or more. In theory 12 gauge wiring can handle up to 2400 watts, but to get that you would have to raise the amps to 20 and generally that is bad all around. For wiring getting hot causing a house fire and electric shock from 20amps will likely stop your heart. So yeah the PSU is under-volted and probably working really hard. A high end PC needs like a 600-850 watt PSU. It's best to get a green energy Gold or Platinum rated one instead of silver or bronze PSU. They are generally better voltage regulated anyways and more energy efficient. If you can find one that is 100-120VAC that would be ideal. Try and maybe lower the PSU watts 350-450 if you can get away with it. The computer may not like that very well and you would be dealing with the same problems.
Edited by technonymous, 01 November 2015 - 08:37 AM.