Power leak from neon sign blamed for baby girl's death in Trang

[Artisi]

An electrical leak on a ungrounded machine will take the easiest path to earth when energised. Like a little girl touching it.

It would be a shame if they did not use this incident to highlight the importance of grounding electrical installations properly and educate the public better.

Ah, we would call that a ground fault I believe. Current that wants to travel somewhere but has no ground for it.

We have GFCI's (ground fault circuit interrupters) that easily trip anytime there's a ground fault. They are installed in all kitchen, bathroom and garage outlets - anywhere there might be a wet floor. So if you touched something hot that wasn't grounded, the GFCI would instantly trip before you even felt a shock. Of course anything electrical is also carefully grounded including all buildings, signs, plugs, lights, etc.

You must be livin in lala land! Not thailand

Sent from my GT-S5310 using Thaivisa Connect Thailand mobile app

What has ensuring your electrics are installed correctly and your life is protected got to do with living in lala land. What ever you drink early in the morning I would suggest you stop immediately.

[Artisi]

Double post removed

Edited August 28, 2014 by Artisi

[kimamey]

As usual, a lot of TV members are electricians.

RIP Little One...........

Many are and many others well understand basic electrics - sufficient to make reasonably informed comments.

Absolutely right. There are many on here that have electrical knowledge. I don't have much although my father was one but it doesn't require much knowledge to understand basic electrics and the reason for earthing.

[KhnomKhnom]

1 Jail for owner/responsible persons.

2. Burn the filling station to the ground.

[Mudcrab]

As usual, a lot of TV members are electricians.

RIP Little One...........

Many are and many others well understand basic electrics - sufficient to make reasonably informed comments.

Absolutely right. There are many on here that have electrical knowledge. I don't have much although my father was one but it doesn't require much knowledge to understand basic electrics and the reason for earthing.

I wonder what people really understand about earthing as opposed to equipotential bonding.

Anyway blame the plumber....all these electrical leaks...running down the footpath....getting in the drains.

[Benmart]

Investigate, prosecute, and publish countrywide the findings and results of the prosecution if guilt is found.

Follow that up with a complete, comprehensive revamp of construction and installation standards, complete with code enforcement, inspection and consequences for those that put people at risk of being killed or injured.

Perhaps adopt the Singapore model of construction and electrical installation. They are a member of ASEAN and may be more pallitable towards acceptance.

[Greer]

Just to make things clearer, the earth and the neutral are bonded together (the point where this is done may vary from country to country in compliance with different regulations). The reason is that the active phases (of which there are three, but usually only one per house in most domestic installations), supply current that returns via the neutral. In the event that a short circuit occurs through the earthed circuitry and say the outside of a kettle or toaster or some such device (or an ATM in this sad case), the high current that flows from the active, via the short into the case of the device and thence to the earth conductor system and eventually back to the neutral, will be a high surge, and that surge will blow the fuse, or drop the breaker, thus isolating the device and protecting the supply circuitry from overload (that could cause a fire), as well as shutting down the supply to a device which is faulty, and potentially deadly if touched.

Bear in mind that a correctly earthed device will not have a high enough voltage on the outer surface to do any damage, as the metal case (or exposed metal components) are earthed, and the fault should not be able to last for anything longer than probably a few hundredths of a second before the protection device ruptures or switches off.

The earth and the neutral are joined so that any device which is connected to the earth will have it's exposed metal components at the same potential as the neutral and the earth, and will be safe to touch.

An ELCB or core balance system works by sensing the amount of current being fed TO the device through the Active, and the amount returning via the Neutral - where no current is leaking to earth, the incoming is exactly the same as the outgoing, the system is in balance and the device detects that nothing is wrong. If there is a short to earth, there will be more current in one of the two circuits than the other, and this difference is detected, and when it reaches a preset threshold, the control circuit in the breaker, disconnects the supply by tripping the breaker to OFF. This usually happens within a few milliseconds.

Note however, that in order for a trip to occur, there MUST be a flow of current to earth, which then triggers the device to switch off - in other words, a human who touches a live wire or outside of a faulty toaster or whatever, CAN get a shock from a system protected by an ELCB, but if all is working properly (and these should be checked regularly by the way), the shock will be for an extremely short duration, and will usually only result in a scare and frazzled nerves.

If no ELCB is in place and the outside of a metal device (washing machine or whatever) becomes live through an internal short to the case, and the earth is not properly connected, then the voltage on the outside of the case will produce a current flow to earth through a human who touches it, and if there is nothing to shut down the power, this can kill.

A fuse or a normal breaker does NOT protect against this sort of thing, as they require a large fault current to flow in order to rupture, but the human will not pass sufficient current to blow the breaker. A human can be killed by, on average, about 30 milli-Amps (mA - thats 30 thousandths of an Amp), which is a very small amount of current, whereas the typical circuit breaker in a home may be rated at 15 Amps or more (that would be 500 times more than it takes to kill the average human for example).

Edited August 28, 2014 by Greer

[Artisi]

Just to make things clearer, the earth and the neutral are bonded together (the point where this is done may vary from country to country in compliance with different regulations). The reason is that the active phases (of which there are three, but usually only one per house in most domestic installations), supply current that returns via the neutral. In the event that a short circuit occurs through the earthed circuitry and say the outside of a kettle or toaster or some such device (or an ATM in this sad case), the high current that flows from the active, via the short into the case of the device and thence to the earth conductor system and eventually back to the neutral, will be a high surge, and that surge will blow the fuse, or drop the breaker, thus isolating the device and protecting the supply circuitry from overload (that could cause a fire), as well as shutting down the supply to a device which is faulty, and potentially deadly if touched.

Bear in mind that a correctly earthed device will not have a high enough voltage on the outer surface to do any damage, as the metal case (or exposed metal components) are earthed, and the fault should not be able to last for anything longer than probably a few hundredths of a second before the protection device ruptures or switches off.

The earth and the neutral are joined so that any device which is connected to the earth will have it's exposed metal components at the same potential as the neutral and the earth, and will be safe to touch.

An ELCB or core balance system works by sensing the amount of current being fed TO the device through the Active, and the amount returning via the Neutral - where no current is leaking to earth, the incoming is exactly the same as the outgoing, the system is in balance and the device detects that nothing is wrong. If there is a short to earth, there will be more current in one of the two circuits than the other, and this difference is detected, and when it reaches a preset threshold, the control circuit in the breaker, disconnects the supply by tripping the breaker to OFF. This usually happens within a few milliseconds.

Note however, that in order for a trip to occur, there MUST be a flow of current to earth, which then triggers the device to switch off - in other words, a human who touches a live wire or outside of a faulty toaster or whatever, CAN get a shock from a system protected by an ELCB, but if all is working properly (and these should be checked regularly by the way), the shock will be for an extremely short duration, and will usually only result in a scare and frazzled nerves.

If no ELCB is in place and the outside of a metal device (washing machine or whatever) becomes live through an internal short to the case, and the earth is not properly connected, then the voltage on the outside of the case will produce a current flow to earth through a human who touches it, and if there is nothing to shut down the power, this can kill.

A fuse or a normal breaker does NOT protect against this sort of thing, as they require a large fault current to flow in order to rupture, but the human will not pass sufficient current to blow the breaker. A human can be killed by, on average, about 30 milli-Amps (mA - thats 30 thousandths of an Amp), which is a very small amount of current, whereas the typical circuit breaker in a home may be rated at 15 Amps or more (that would be 500 times more than it takes to kill the average human for example).

Excellent post.

[doglover]

As usual, a lot of TV members are electricians.

RIP Little One...........

Many are and many others well understand basic electrics - sufficient to make reasonably informed comments.

Absolutely right. There are many on here that have electrical knowledge. I don't have much although my father was one but it doesn't require much knowledge to understand basic electrics and the reason for earthing.

I wonder what people really understand about earthing as opposed to equipotential bonding.

Anyway blame the plumber....all these electrical leaks...running down the footpath....getting in the drains.

Earthing and grounding are indeed the correct terms. As the the metal casing must be grounded/earthed.

For equipotential bonding there would have to be metal grating installed on the sidewalk and grass around the machine which is equipotentially bonded to the ATM machine casing which is grounded/earthed.

[whaleboneman]

I'm not sure where Greer is from but I doubt that all current returns through the neutral. In Canada houses are supplied with 2 phases and a neutral. Thus we get 120V between a hot and neutral and 240V between two hots. The neutral only carries the difference between the two hot legs. And since it's AC it's merely cycling back and forth at 50 or 60 cycles per second (Hertz). Not really returning anywhere.

[happytobehere2014]

Very sad,, may she rest in peace. Heard of case in Pattaya a few years ago where a shower was installed at this English guys house; spent 10 million plus, so you would expect decent standards of work. His wife was first to use it and was electrocuted, died instantly. They guy died of an illness 2 years later and 2 little girls were left as orphans. Time for some tough legislation l think.