Electric Shocks In Thailand

[syd barrett]

I have had a number of electrical shocks off electrical appliances in Thailand, first my computer chassis, then a particularly nasty one off my microwave oven chassis. I reckon if I'd had wet feet, I'd be dead.

My conclusion is the two-pin system. All power appliances should have an earth (ground). It even says in the microwave instruction manuel; 'This appliance must be earthed' yet it came as a two pin plugged item.

I can't very well change all the electrics here to three pin, anyone have any suggestions? Surely there are some electricians out there with a bright idea, or will I have to craft a pair of slippers out of porcelein, or wear gum boots.

Yours in a highly charged state,

SB (is this a moslem smile?)

[sbk]

We have had this problem but only with minor appliances. my husband says your microwave should have come with a grounding wire. It should be screwed to the back of the microwave and then run into the ground. Directions should be in the manual. As for the computer, we have our actual socket grounded, again, a ground wire running from inside the socket box to a long metal thin pole in the ground. No more scary shocks off the computer, and no more fear of frying my camera. Hope this helps.

[plachon]

Syd,

I have a suggestion.................trade your computer in for a manual typewriter and your microwave in for a charcoal stove. It'll solve your shocking problem and all the other stresses and strains of modern living in one fell swoop. And if you have a car, a two cow-pulled khwian is highly recommended for alternative means of transport. Believe me, it moves faster along the chonabot roads than the average speed of traffic in bangkok (which was about 8 miles an hour, last time I checked the Big Durian's streets).

[Khun ?]

Many countries tie earth and and return grounds together, sounds like you maybe have neither or just a poor return ground system. Temporary get an adapter and

make a clip on one end of wire and hook it tightly to a water pipe/faucet close by and the other to the adapter safety ground side for 3 prong.

until you can either stop using appliances or get the ground fixed at the circuit breaker panel. At least with a poor grounding system you will not have many circuit breakers popping or fuses blowing.

[maerim]

What the problem is here is that the voltage is 220-240 volts AC most of the time no volts some of the time and no earth any of the time.

Your problem won't be solved by earthing your equipment although you can try it you need a earthing rod, a piece of copper bar thats whacked into the ground and a cable clamped to it that terminates at the fuse box.

What you need is an R.C.D.a residual current device, you can buy whats called a "safe t cut" from the local ironmongers that you put in between the device and the fuse box.

This theorectially should trip the switch if there is a problem but as it's made here I wouldn't trust it with some one elses life let alone mine.

I posted a reply to Stu as he want to come and live here, what I suggested to him is that he buys the next time he comes here from the U.K. a consumer unit, thats the thing with the fuses in it.

As the U.K. has the most stringent safety regulations in the world the stuff you get there is very good.

I have wired a few houses here with these. I generally use a Wylex consumer unit with at least 8 ways one way = one M.C.B.(miniture circuit breaker) you don't have to use them all buts it's handy just in case, buy one with a split load option and a R.C.D so you get two main switches if you do buy one of these make sure you get the mcb's with it as you can't buy them here.

Fuses won't work they are there to protect the appliance not you so about 5 or 6 of us could all hold hands and then try and contact the living

If you know someone in the U.K. ask them to get you one, the Thai sparks can wire these up for you but in the meantime you can try using the "safe t cut "they are about 120 baht.

These consumer units are not cheap but it is better than being dead

[maerim]

Khun

That won't work as the water pipes here are plastic.

If the incoming is steel ok but most places they are plastic.

[Guest IT Manager]

Casting our minds back, we will remember an earlier post.

Listen carefully. Take a drill or a nong that knows how to drive one and dig a hole through the wall.

Take a piece of 2.5 square mm wire, preferably green and push it through.

Take a piece of copper coated steel, available from the hardware for about 60 baht, and drive it into the dirt near the wall.

Wrap the wire around it and using a pipe/hose clamp of an appropriate size, connect the two.

Connect the bit inside the wall to one of the four screws holding the round fan cover in place on the back of the PC.

Change the wall plugs to 3 pin and connect the same bit to the third pin in the plug sets. Now you have an earth. Use it.

If you're in a condo this may be hard but the principle is the same.

[KevinN]

Firstly,Always wear Rubber thongs,so your bare feet are not directly on the tile.

Then get your self down to the electrical supply store,but new romax wire that is 3 wire,rewire everything to the 3 wire,put on grounding 3 prong plugs with the ground wires attached and you can buy the copper rod for the ground outside,drive it in the ground and hook your wire to it with the clamp that is furnished.

When we built our new house,I insisted that everything be 3 wire and so now the reefers,computers and microwaves,water heaters and everything that runs on electric is on the 3 wire grounded system.

But in the mean time,if you get a shock,try turning the plug over,as this helps most of the time,but will not replace the 3 wires that are required in most countrys.It has nothing to do with if you have 120 or 220 AC 50 or 60 cycle power.

[maerim]

Now I have had a kip I did mean to say "might" instead of "won't" solve the problem.

What you should also do is to investigate why the chassis of the microwave and other appliances are "live" a lot of stuff made these days is double insulated so you don't need an earth.

There again the quest for longevity has not really caught on here yet.

[Pink Mist]

maerim you are right to investigate the reason for the boots from the chassis of microwave as kevin suggests try turning the wiring on the plug around as they may have the active and neutral swapped, still none of the wiring should be touching chassis. The only place a neutral and earth should have a connection is in a main switchboard in a M.E.N. system. In Oz all house wiring should have at least 2 megohm reading to earth and appliances should follow this lead also. I guess some manufacturers in asia dont follow this standard.

If you install R.C.D devices and there is any discrepancy in the Active and Neutral currents the device will trip. These used to be called earth leakage devices but was a misnomer as I said it measures the difference between Active and Neutral. We used to have a lot of trouble in the early days fitting of the devices with older friges because the insulation wasn't up to it.

When you mentioned double insulation maerim this wouldn't apply to a microwave, for a start wherever you have cabling snaking around inside a conductive metal container it needs to be earthed in case wire breaks touches side and zzzzt when you touch it without the thongs on.

Check your microwave and put in earth stake and use M.E.N. system and you will be O.K.

bronco

[lopburi3]

There are several things that need to be done in your case. As IT/M says install a ground rob and if you can not use it to house wiring at least attach to those items of concern (computer/microwave) and any refrigerator. If you can; rewire home with 3 wire cable and grounded outlets (but make sure the plugs have grounds - most now seem to come with round pins with the ground missing when bought - either change or find a source of these pins and install). If in an apartment you might get landlord to foot some of the cost. Work is really not too expensive when you consider it could save your life. But make sure they attach system to a ground rod.

Until grounds, and even after, install ground fault circuit protection. This can be one unit such as Safe-T-Cut installed at main circuit breaker. It won't stop the shock but should cut current before you die.

Walking barefoot does have its downside.

[Khun ?]

Current flows from ground so a bad ground means weak current which when you touch the item gives it another way for current to get to the item. Thinking he may be on the 10th floor of condo running wires and installing grounding rod with a bit of salt and charcoal to draw and hold water for conductivity around the grounding rod is the norm. Water is conductive and provides a good source to ground through leaking into the ground itself. Knowing that many places are now

PCV pipe they normally build up a moist residue throught the pipes over the years

thus providing a moist path to groundthru the residual moist sludge in the pipes ( turn the water on before using the appliance may help if you ground to the sink in the kitchen where most appliances are if you are on a high floor with no way to run wires to a moist copper grounding rod.

Nuetral is the correct terminolgy on a AC circuit it is neither positive nor negative

in respect to alternating voltage. Desert areas always have problems with the ground it is to dry the dirt/sand so must be watered most of the time ie; special grounding at transfer stations and housing required. In humid areas with products

being made cheap different metals are used causing corrsion in the wiring systems

which will leak onto the chassis and with a bad grounding system you become a path for electron flow. Circuit breakers and current limiting devices are not much use on badly grounded systems as you have a lack there of. Copper grounding rod and wiring is great and it does not corrode similar to gold but it will build up a

bacteria substance on the outside of it.

[Pink Mist]

The bacteria substance you refer to khun is actually a chemical reaction on the copper, it occurs more in hot moist climates and is called "Verdi grease".

Dont ever rely on pvc pipes for a ground no matter what has built up inside.

As has been said here many times here use a three wire system, active, neutral and earth.

[lopburi3]

Circuit breakers and current limiting devices are not much use on badly grounded systems as you have a lack there of.

If you are saying RCD or GFI do not work on ungrounded AC circuits you are very wrong. They work and they save lives. Circuit breakers are designed to trip at a specified current level and they also work. But this level is usually too high to prevent death if you are the fault path so that is the reason for ultra sensitive RCD/GFI devices.

Current flows from ground so a bad ground means weak current

No. The ground in AC provides an alternate path (rather than through you) for the current to flow/trip a circuit breaker - it should never have current flowing in it. The flow should be between active (hot) and neutral. If you have a hot ground you have a problem.

[Khun ?]

Circuit breakers and current limiting devices are not much use on badly grounded systems as you have a lack there of.

If you are saying RCD or GFI do not work on ungrounded AC circuits you are very wrong. They work and they save lives. Circuit breakers are designed to trip at a specified current level and they also work. But this level is usually too high to prevent death if you are the fault path so that is the reason for ultra sensitive RCD/GFI devices.

Current flows from ground so a bad ground means weak current

No. The ground in AC provides an alternate path (rather than through you) for the current to flow/trip a circuit breaker - it should never have current flowing in it. The flow should be between active (hot) and neutral. If you have a hot ground you have a problem.

If you are saying RCD or GFI do not work on ungrounded AC circuits you are very wrong. They work and they save lives. Circuit breakers are designed to trip at a specified current level and they also work. But this level is usually too high to prevent death if you are the fault path so that is the reason for ultra sensitive RCD/GFI devices.

I guess you are right on these RCD's and GFI's. I never used them before never seen them before nor looked for them. I am interested in how they work as it says they are mainly used for walk around appliances such as electric razor, jack hammers, no mention of microwaves 1000 watt appliances but toasters were mentioned.

I mainly use a 3 ground system and never tie Neutral and Safety ground together.

Maybe the guy just has cheap wall sockets or plug adapter that after a period of use the prongs ( contacts) inside the wall sockets become a bit loose. This is where most fires start

when caused by electrical system, wires heat up become brittle over time due to loose or wrong size wires and sockets or sockets that are continuelly installed and removed such as a vacuum cleaner being plugged in. Anyways they have enough info to read now. Thanks for the knowledge of RCD and GFI's

[translator]

Safety is the utmost imporance for your survival instincts.

whack a steel or copper pile in to the ground and thread a good grade cable around the house. put three pin on everything and connect to it earthly like.

live long and prosper

or...buy good quality wellington boots - good resistors for your needs.

[Guest IT Manager]

If I install a computer in a house and it kicks, I earth the chassis. IMHO take each appliance out of the system (unplug it), then plug one in at a time to see if it kicks. eg:

Disconnect everything, plug in the PC. Does it kick, yes/no, if no leave it in and go plug in the microwave. See if it kicks. If you don't want to be the test pencil, go and buy one for 30 baht. As you plug in an appliance it will have hot earth or not. If it does, so will everything else. Neutral is manufactured by grounding the star point of the first transformer in the medium voltage system.

You generate at 11,000 volts, 10,000 AMPS, you transform to transmission line voltage either 333,000 or 300,000 at 1000 amps. (approximately).

You fed on pylons to local area distribution systems who transform back to generator voltage (11,000) and then distribute to pole top and street end transformers. (3 wires on single insulator about 6" high). Look for the transformer nearest you, it will have four wires leaving it at 380 volts (approximately) and 3 phase. At that point, you will find an earth-neutral link). Thats where the neutral is developed or manufactured. It's a cheat.

Test the earth on the second appliance. If yes, go test the PC, if no plug in the next item.

The major contributor in my experience has been the power supply on the PC. Ground one thing you ground all.

Make your own earth and all will be fine.

Everyone else is correct as well, mine is just cheap because I am keenio.

[Pink Mist]

does anybody want earth stakes or rcd will send container over from clipsal

[lopburi3]

does anybody want earth stakes or rcd will send container over from clipsal

Clipsal is available here in Bangkok as have two of their RCCB power panels in my home.

But as good as grounding is highly advise everyone to use GFI/RCD protection here in LOS where we normally don't wear shoes and floor is a good ground. If you come in contact with a hot light socket and such that are not normally attached to a ground it can save your life.

[wilson steer]

Delta Star Transformers in Thailand are badly installed, the secondary neutral should be connected to the earth electrode. Bad Phase/Impedance 3 phase problems persist due to bad planning. Neutral should be near zero potential.

Reverse the 2 pin sockets to avoid shock. If that does not work create your own ground.

I think Thailand should be made a compulsory D.C. system as Edison himself championed!

[Guest IT Manager]

The bacteria substance you refer to khun is actually a chemical reaction on the copper, it occurs more in hot moist climates and is called "Verdi grease".

Is that the same as verdigris ?

[andy50]

make sure you use a 30ma (milli-amp) rated rcd,(residual current device),this should trip the electricity before it does you any harm .it should be tested each week also by pressing the test button on it .although thai plugs have 2 pins-i thought they also hade a strip inbetween the 2 prongs that is the earth?

[Pink Mist]

Same stuff I reckon IT never knew the correct spelling but had to deal with it at various times. I assumed (never assume) it was verdi, from verdant green and grease because of it's oily greasy texture. It is something we were never taught at TAFE in my day but you learnt about it on the job.

bronco

[dr_Pat_Pong]

So many electricians hereabouts, it is shocking .

[lopburi3]

although thai plugs have 2 pins-i thought they also hade a strip inbetween the 2 prongs that is the earth?

Most Thai plugs are Japanese (US TYPE) two flat blade with a smaller number of the European two round pin type. Almost all outlets accept either of these. They do not provide for any ground.

Many computer components now use the US type three pin (two flat/one round) plug and are wired with a ground wire. Unfortunately most "outlet" strips accept this plug and then end with two pin plug (or adapter) and no ground. Many electric items now on sale have the European grounded plug (without the ground pin but with metal strip on side) which is useless in Thai outlets. All the more reason to have and use Safe-T-Cut or other such GFI/RCD device. Don't take anything for granted.

[andy50]

hi lopburi,its all a bit conFUSING to say the least,

[Pink Mist]

yes doc I find it hard to insulate myself from this thread

[lopburi3]

hi lopburi,its all a bit conFUSING to say the least, 

make sure you use a 30ma (milli-amp) rated rcd,(residual current device),this should trip the electricity before it does you any harm

Which is why your 30ms advise is so important here. What may only be a small shock in our homeland can be fatal here because of the customs/construction/ hot and humid weather/and general absence of proper grounding. Those 'fuses' don't do it all.

[Pink Mist]

Any decent RCD will have 2 ratings and they were both mentioned in lopburi3 post.

a ms rating which is trip time in millisecs 1ms=.001secs and a ma or milliamp rating 1ma=.001amps. The lower the numbers the better protection ie 30ms and 30ma means the device will trip at a current greater than 30milliamps in 30 milliseconds.

There are much faster devices around on the world markets. My company supplies personal RCD's to be used when using power tools etc. and these trip in 10 ms, you cant even feel them.

bronco

[dr_Pat_Pong]

Ohm on the range.