240Volt Electrical Question

[masuk]

I've just moved into a new place, and all my new appliances have 3-pin plugs and warnings that these must be earthed. The whole house was 2-pin.

An electrician came over and installed plugs as required, including one in the spare room for my computing gear.

Now, the question is this: I bought a 3-pin overload and lightning protection board last trip to Oz, but when I plug it in, the warning light comes on to say it's not functioning correctly.

So I put a multi-meter into the outlet, and it shows the correct voltage across active and neutral, but it also does the same from active to earth i.e. 240 volts. Whenever I did this test at home, the active to earth voltage was way lower.

The question is: are these outlets really earthed? I know he's run a copper earthing rod deep into the ground, correct cable and so on, in fact a very professional job, but what happens if the microwave or the washing machine go live? Houses here don't seem to have Earth Leakage Detection.

[WinnieTheKhwai]

what happens if the microwave or the washing machine go live?

I usually keep the doors locked and wait until they settle down, then when they're off-guard I jump in and unplug them.

[eyecatcher]

excuse the pun ..but its safe to assume certainly older properties are NOT earthed as you would expect in farangland. I cannot say for new properties and maybe many are adopting Western standards.

You will notice many "flashes" when you plug in or out, and I for one daft as it is, alway plug in with 2 fingers on the edge...just in case.

To earth the property means taking an earth wire to each and every socket.

Its not essential but in the first instance:

make sure your hands are not wet!! and in the 2nd instance:

get the Mrs to plug it in!

[jpinx]

It's unusual to find a properly earthed house ring main. The best you can do it check between the negative and earth sockets. If there's a voltage across those you have a problem. Start isolating the sockets one by one till you find the faulty one. Wear dry rubber boots

[masuk]

Well, the electricians must have great faith in their work, as they work bare feet on the tiles floors!

Nice to see we've retained our sense of humour!!

[eyecatcher]

It's unusual to find a properly earthed house ring main. The best you can do it check between the negative and earth sockets. If there's a voltage across those you have a problem. Start isolating the sockets one by one till you find the faulty one. Wear dry rubber boots

and use an electrical screwdriver.....it lights up before you do!

[JeffreyMcCollum]

I've seen it time and time again.

The electriction comes out and adds the 3 pin (grounded) outlets that you see but not the wires.

To do it correctly you most likely need a new main box and all new wires all throughout your house. I did it in mine, took 2 weeks. Cut into every wall for every switch, outlet, plug, light, etc. Yes a pain and a mess, but I know mine is now to UBC regulation. (california building codes)

And if you really went all out youd add GFI outlets in wet areas or a whole house unit.

your safety, and life may depend on it some day

[eyecatcher]

And if you really went all out youd add GFI outlets in wet areas or a whole house unit.

your safety, and life may depend on it some day

is this the same as earthing the wc, basin, urinal...porcelain to copper.

Potentially Its no joke taking a pee in the urinal when the lightning storm is outside....its shocking

[kaptainrob]

I rewired 70% of a 40 y/o house in Ubon and installed 5 circuit breakers with an earth on 2 circuits: new water pump + shower HW heater. Previously, all old lighting and GPO circuits ran off one knife switch with inline 15amp fuse and no EARTH. Each time family gathered with TV and stereo blasting the fuse would blow....

[Paagai]

Not to underrate the importance of proper earthing, but earth Leakage protection at the supply should be first on the list! Easy to add at the main supply entrance. e.g. SafeT-Cut http://www.safe-t-cut.com It should help if you unwittingly become a substitute for the missing earth

The earthing will only be as good as the Electrician who installs it. I once watched one chump here bang a piece of rebar in the ground and strip 5cm of a 1.5mm² earthcable which he loosely wrapped around the rebar and covered with insulating tape.

[Litlos]

To original OP. The voltage between active and earth/neutral should be the same within a few volts if all is working correctly in the Aust installation. Here by the sound the sparky has either done it correctly (unlikely) or put in a link between earth neutral on the sockets or somewhere. BTW plugs are male and sockets are female so I think you got new sockets not plugs.

As above with the way the whole Thai electrical system is organised(?) best thing is to get a Safe-T-Cut or similar installed. This will protect you.

Cheers

[justcruisin]

Masuk,

it looks like they have crossed over somewhere with the neutral and earth, I have a newish apartment and it was the same. Takes a bit to find as you have to isolate every outlet and check back to the switchboard to find the problem.

Unfortunately there is no electrical licensing or even basic wiring knowledge/skills in this country!

Pagaai,

I didn't know you were a technical type person, but also a brilliant suggestion, almost imperative to install a safety cut at the switchboard. A few months ago I got a bad 240 shock from a shower unit at room I recently stayed. I was very lucky not to be killed. There are many deaths every year from lack of earth leakage protection.