Dangerous Electric Grid

[hawaiiman]

Noting that as many as 50 people died in the recent floods from electrocution, a word or 2 seems appropriate. Thailand's 220v system only requires 2 hot wires to function. 110v systems require a single hot and a neutral. Electrical standards in usa require the house to have a system of chassis grounds. This prevents the metal body of appliances from being charged with potentially lethal voltage. There is nothing wrong with 220v, in fact it has less line loss and uses much less copper than 110v. I believe the distribution grid in Thailand has a system ground wire. The problem is, most homes and businesses do not have a chassis ground system because they only use two conductor wire in the interior wiring. Turn on your computer, take off your shoes and touch the metal back of the computer and you will get quite a jolt. Many modern appliances are starting to be supplied with a three prong plug. The third prong is connected to the appliance chassis. As much of the household and business wiring is stapled to the interior walls, it wouldn't be too difficult to rewire with a 3 wire conductor which could then be connected to the ground of the grid.
I am certain that the incidence of injuries and death due to electrocution would be greatly reduced.

[pjansen]

This isn't about grid facilities. You can do proper grounding yourself (by putting a copper tube into the ground for 1 meter or more) and earth leakage and safety cuts aren't grid facilities; they are facilities that belong to "your" perimeter. Last year I redid all wiring in my house and (without changes from the grid) had all these facilities installed. (Being an electrical engineer myself, I am kinda fussy about these kind of things - even without the current flooding problems)

My point is - It's about budget when you install your electric facilities and about what kind of installations are allowed to be installed, sometimes by unqualified engineers.
Wether to use 110V or 220V is irrelevant. 110V AC can kill just as easily with your feet in the water and your hands touching the active line.

[hawaiiman]

Looking at the service to my house, there are only 2 wires going to the meter. From a safety standpoint it is not possible to do any work on the service side of the meter. Installing a ground rod, although in theory a great idea, isn't practical in locations which are covered with cement, or have dry or hard soil for much of the year for example. Going down one meter or more isn't going to provide protection in dry soil or non conductive media. If one lives on an upper floor of an apartment building, driving a ground rod may be..difficult
If there are not 2 hots and a neutral supplied though the meter, then safety cannot be assured. If the grid does not supply access to the system ground, then the primary issue is with the grid.
Safety starts with the grid and works outwards. Given access to a safe hookup, a property owner can then follow up with a safe installation.

[hawaiiman]

Another issue: power switches in some appliances, especially multi outlet extension cords,which only switch one side of the circuit. I would guess most of them are manufactured this way, as the one I took apart recently was. Obviously in a 220v system this leaves a hot wire connected even when switch is off. Combined with 3 to 2 wire adapters and wall outlets that allow plugs to be inserted either way this is a recipe for electrocution.