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How safe are wall mount water heaters without earthing ?


rubberduck

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Every year locals and foreigners are killed due to unsafe waterheaters. I recently stayed in a hotel for few weeks and when taking an unearthed shower and I often get the feeling 'nothing should go wrong cuz then I'm dead'.

But how dangerous are this water heaters exactly when no earth connection is mounted ? I estimate in Thailand 90% is lacking earthing.

normal_thailand_hot_water_heaters_shower

Edited by rubberduck
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.....circuit breaker (safe-T-cut) is essential. When I moved in I was puzzled by the nails attached to the circuit and stuck into the ground. I since found out that this was the earthing...If I had the expertise I would buy some European plugs and sockets, meaning that I couldn't plug many of my Thai power tools.

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Has anybody seen the temporary lighting that Thais set up at parties or weddings? They run a 2 wire cable through the trees or whatever back to the nearest mains supply, and then go around hanging light fittings with bare wires to each of the cables - attached with safety pins through each of the copper cores. The biggie is that they attach the safety pins while the circuit is live (and in the rain) - funny as a fight when somebody touches both safety pins and gets zapped.

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The Safe-T-Cut breaker he's talking about - the necessity of which is critical I agree - is a separate upstream unit, often installed at the breaker panel.

Sometimes in the bathroom where water could splash on it, defeats the purpose I think.

But nothing substitutes for proper grounding, not just for safety's sake but the longevity of your electronics - expensive ones should be on a UPS anyway as well, even if your house's systems are perfectly setup the mains supply quality here is uniformly poor.

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.....circuit breaker (safe-T-cut) is essential. When I moved in I was puzzled by the nails attached to the circuit and stuck into the ground. I since found out that this was the earthing...If I had the expertise I would buy some European plugs and sockets, meaning that I couldn't plug many of my Thai power tools.

The circuit breakers inside your consumer unit are NOT life saving devices, they are high rated amperage circuit breakers that only the LIVE wires run through them, not the NEUTRAL and they

don't detect earth leakage.

They are designed to protect the wires from melting or catching fire in the event of a short circuit

they will NOT prevent electrocution as they can withstand the amperage stated on them before

self switching off, which by then, could well be too late.

I agree but it is better than nothing and easy to install.

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The Safe-T-Cut breaker he's talking about - the necessity of which is critical I agree - is a separate upstream unit, often installed at the breaker panel.

Sometimes in the bathroom where water could splash on it, defeats the purpose I think.

But nothing substitutes for proper grounding, not just for safety's sake but the longevity of your electronics - expensive ones should be on a UPS anyway as well, even if your house's systems are perfectly setup the mains supply quality here is uniformly poor.

You don't need to install an ELCB inside your bathroom it can easily be installed at or next to the consumer unit

taking the wires from the water heater circuit breaker, this is the safest and easiest way to install one.

Or you can buy consumer units with ELCB's already incorporated.

All three reasons below are essential for 100% safety:

1) Circuit Breaker

2) ELCB

3) Earthing

Without all three working in unison you are NOT 100% safe.

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Most of el. appliances in Thailand are sold with a two pin plug, which is A (active) and N (neutral).

Unless the appliance states: "Double insulated. Do not Earth", it is UNSAFE!

Now, if your appliance has three pins - does not mean you are safe. The Earth wire must be enacted in your socket (plug in point on the wall)

9 ot of 10 chances it is NOT!

Here is an easy safety check anybody can (MUST) do at home:

Get a 230-240V el. bulb (the usual incandescent type - with hot filament) fixed in a normal patron with two insulated wires connected to patron's A and N

points. The wires should be about 20-30 cm long. Cut off insulation at the tips of each wire about 1-1.5 cm. Holding at the insulation!!! stick in the bare wires into the wall socket.

If the wall socket has two points only - there is no Earth. Replace if you want to be SAFE.

If the wall socket has three points (holes) - one is A one is N one is E.

Stick bare wire ends into A and N - the lamp must be 'ON".

Stick the bare wire ends into A and E - the lamp must be 'ON'.

Stick the bare wire ends into N and E - the lamp must be 'OFF'

Remember - three combinations must be performed on each plug point.

Anything not like described above - NOT SAFE. If the room is yours - call electrician and REWIRE. Costly!

If you are renting - demand the owner does REWIRING. If he refuses - move or take a risk, - up to you, as Thai say...biggrin.png

Have a good life!

The rules above are for Australia. This is TITs. They may have a "Safety First" sticker instead of compliance with Aus. safety rules. Don't remove the sticker and cross your fingers. It helps...cheesy.gif

Alternative test you can try: Stick the bare wire ends into your TITS. If the lamp goes 'ON' - you are HOT!!!giggle.gif

Edited by ABCer
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They have the potential to electrocute you if they are not earthed

and an internal fault occurs.

Not only that but they also need to be protected with an ELB

(earth leakage breaker) that is fitted in the supply line through the

Live and Neutral.

Only earthing is NOT 100% safe.

And the ELCB has to have a reference to an earth to function as designed and intended.

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Most of el. appliances in Thailand are sold with a two pin plug, which is A (active) and N (neutral).

Unless the appliance states: "Double insulated. Do not Earth", it is UNSAFE!

Now, if your appliance has three pins - does not mean you are safe. The Earth wire must be enacted in your socket (plug in point on the wall)

9 ot of 10 chances it is NOT!

Here is an easy safety check anybody can (MUST) do at home:

Get a 230-240V el. bulb (the usual incandescent type - with hot filament) fixed in a normal patron with two insulated wires connected to patron's A and N

points. The wires should be about 20-30 cm long. Cut off insulation at the tips of each wire about 1-1.5 cm. Holding at the insulation!!! stick in the bare wires into the wall socket.

If the wall socket has two points only - there is no Earth. Replace if you want to be SAFE.

If the wall socket has three points (holes) - one is A one is N one is E.

Stick bare wire ends into A and N - the lamp must be 'ON".

Stick the bare wire ends into A and E - the lamp must be 'ON'.

Stick the bare wire ends into N and E - the lamp must be 'OFF'

Remember - three combinations must be performed on each plug point.

Anything not like described above - NOT SAFE. If the room is yours - call electrician and REWIRE. Costly!

If you are renting - demand the owner does REWIRING. If he refuses - move or take a risk, - up to you, as Thai say...biggrin.png

Have a good life!

The rules above are for Australia. This is TITs. They may have a "Safety First" sticker instead of compliance with Aus. safety rules. Don't remove the sticker and cross your fingers. It helps...cheesy.gif

Alternative test you can try: Stick the bare wire ends into your TITS. If the lamp goes 'ON' - you are HOT!!!giggle.gif

As you say these are Australian rules, I have carried surveys throughout Asia and each country is different. As the existing wiring goes ELCB's do not work here unless you fit an Isolating transformer and then a separate earth line. The power supply coming into domestic property has no earthing and as a previous writer says the safety T Cut are for overload and give little protection to the human body. There is little you can do here to make showers safer other than keep isolating switches out of the bathroom and water away from the unit. Best of luck.

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They have the potential to electrocute you if they are not earthed

and an internal fault occurs.

Not only that but they also need to be protected with an ELB

(earth leakage breaker) that is fitted in the supply line through the

Live and Neutral.

Only earthing is NOT 100% safe.

Absolute <deleted>, if there is correct earthing and the heater element becomes live then the current will flow to ground through the earth which should then trip the circuit breaker. By correct I mean at least a 10mm earth cable and all metal pipework bonded to ground as well (not sure of exact UK requirements now as I don't live there and I'm industrial not domestic). In the UK it is not a requirement to have an rcd fitted, only required for new installations. Also an rcd device doesn't need an earth connection, it just looks at the current imbalance between live and neutral - i.e. current in is the same as current out.The problem I have seen here is that they don't connect the earth at the at the consumer unit to the house wiring and also at one friends house I saw the bonding for his metal roof struts earthed with a 1mm wire which would vapourise if there was a lightning strike. The one thing that makes me nervous with electric water heaters is that the mains supply to the house comes via overhead lines and liable to lightning strikes although at the moment I live in a condo so I'm protected by the 3 phase incomer transformers and switchgear protection.

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Ironically, most "earths" in Thai construction are there for decoration only. There might be an earth wire in your house/condo, but try and figure out if it actually goes to a decent ground of any kind. I've never yet seen an earth pole and strap outside a house or business.

Top prize goes to the muppet that installed my new water pump. Diligently earthed the green cable between the metal body of the pump and the plastic plinth it was mounted on. I explained the problem, even got the wife to explain with much use of the Thai language app on my phone to explain "earth, ground, plastic, metal, circuit, conductivity" etc. Totally over his head - always done it this way apparently.

The guy that wired a point for our washing machine, did something similar, he ran an earth wire from the washing chassis and then, with a screw, attached it to the concrete floor.

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They have the potential to electrocute you if they are not earthed

and an internal fault occurs.

Not only that but they also need to be protected with an ELB

(earth leakage breaker) that is fitted in the supply line through the

Live and Neutral.

Only earthing is NOT 100% safe.

And without an earth the ELCB is useless.

Edited by Rorri
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They have the potential to electrocute you if they are not earthed

and an internal fault occurs.

Not only that but they also need to be protected with an ELB

(earth leakage breaker) that is fitted in the supply line through the

Live and Neutral.

Only earthing is NOT 100% safe.

And without an earth the ELB is useless.

again <deleted>, there is no earth connection on an rcd and the reason you get an electric shock is because you have made a current path to ground. the rcd detects that the neutral current is lower than the live current so some current is flowing to ground so therefore it does not require an earth. people get killed because of bad advice.

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Ironically, most "earths" in Thai construction are there for decoration only. There might be an earth wire in your house/condo, but try and figure out if it actually goes to a decent ground of any kind. I've never yet seen an earth pole and strap outside a house or business.

Top prize goes to the muppet that installed my new water pump. Diligently earthed the green cable between the metal body of the pump and the plastic plinth it was mounted on. I explained the problem, even got the wife to explain with much use of the Thai language app on my phone to explain "earth, ground, plastic, metal, circuit, conductivity" etc. Totally over his head - always done it this way apparently.

The guy that wired a point for our washing machine, did something similar, he ran an earth wire from the washing chassis and then, with a screw, attached it to the concrete floor.

Concrete floor ??

Concrete is an insulator.

Except perhaps in the rain when is absorbes water.

Ground means "electrical" ground, NOT gravitational ground.

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.....circuit breaker (safe-T-cut) is essential. When I moved in I was puzzled by the nails attached to the circuit and stuck into the ground. I since found out that this was the earthing...If I had the expertise I would buy some European plugs and sockets, meaning that I couldn't plug many of my Thai power tools.

How does safe-t-cut work?

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They have the potential to electrocute you if they are not earthed

and an internal fault occurs.

Not only that but they also need to be protected with an ELB

(earth leakage breaker) that is fitted in the supply line through the

Live and Neutral.

Only earthing is NOT 100% safe.

And without an earth the ELB is useless.

again <deleted>, there is no earth connection on an rcd and the reason you get an electric shock is because you have made a current path to ground. the rcd detects that the neutral current is lower than the live current so some current is flowing to ground so therefore it does not require an earth. people get killed because of bad advice.

Is it complete <deleted>?

He said ELB/ ELCB.

You are talking about an RCD/RCCB which of course doesn't require an Earth as it measures Residual Current and doesn't care how the loss got to Earth?

Whether you approve of them or not, will an Earth Leakage Circuit Breaker function without an Earth?

.

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OK people, enough!!

RCDs and RCDBs do NOT need a ground to function, the old (very old) voltage operated ELCBs did, but I've never seen one in Thailand and they are illegal in most Western countries too, not made any longer.

The term 'ELCB' when used today is normally referring to an RCD.

And for those who want to know how an RCD works: http://en.wikipedia.org/wiki/Residual-current_device

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Ironically, most "earths" in Thai construction are there for decoration only. There might be an earth wire in your house/condo, but try and figure out if it actually goes to a decent ground of any kind. I've never yet seen an earth pole and strap outside a house or business.

Top prize goes to the muppet that installed my new water pump. Diligently earthed the green cable between the metal body of the pump and the plastic plinth it was mounted on. I explained the problem, even got the wife to explain with much use of the Thai language app on my phone to explain "earth, ground, plastic, metal, circuit, conductivity" etc. Totally over his head - always done it this way apparently.

The guy that wired a point for our washing machine, did something similar, he ran an earth wire from the washing chassis and then, with a screw, attached it to the concrete floor.

Concrete floor ??

Concrete is an insulator.

Except perhaps in the rain when is absorbes water.

Ground means "electrical" ground, NOT gravitational ground.

Yeah, we know that and you know that.....the point being that the some of the muppets that install electrical equipment here DON'T, and they think that by attaching an earth wire to anything that touches "the ground" as in terra firma is somehow a necessary part of the installation, regardless if that surface is conductive or not.

I'm just waiting to see somebody attach an earth clamp to a plastic water pipe, and then I'll really have seen it all!!

Edited by Gsxrnz
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Each of those cheap in-shower water heaters cost a 5,000+ for a decent unit. But they are lousy when in comes to GFI (ground fault interrupt), and that's if you even have a ground (earth).

So honestly, if it is your own house it is far more cost efficient and SAFER to install an all-home electric boiler. An 80 liter Feroli boiler can be bought for about 12,000 baht, plus straight-forward piping and smaller capacity units for much less. I can't understand why anyone would use those wall-mount units in new construction other than "stepping over dollars to save nickels", as we say in the states.

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They have the potential to electrocute you if they are not earthed

and an internal fault occurs.

Not only that but they also need to be protected with an ELB

(earth leakage breaker) that is fitted in the supply line through the

Live and Neutral.

Only earthing is NOT 100% safe.

And without an earth the ELB is useless.

again <deleted>, there is no earth connection on an rcd and the reason you get an electric shock is because you have made a current path to ground. the rcd detects that the neutral current is lower than the live current so some current is flowing to ground so therefore it does not require an earth. people get killed because of bad advice.

<deleted>, I didn't say the ELCB/RCB needed an earth attached to it, the "load" MUST have an earth connection, whether this is via the chassis or the human body, in order to provide a path to earth, this then unbalances the ELCB/RCB, tripping the CB. http://electricalnotes.wordpress.com/2011/10/01/working-principle-of-elcb-and-rcb/

Edited by Rorri
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