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Watch Your Feet !


Spee

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Hello All,

Never really thought about it too much before but ....

Thai wiring, especially short term or temporary, can be a bit on the dodgy side. Evidence the image attached with this post, which is an example of how the entertainment team wired up the temporary lighting for my house blessing party this week. I didn't think about it took much at the time, because all the wiring was secured overhead and not directly into the house wiring. Then again, safety pins for fuses is just a bit scary.

http://www.thaivisa.com/gallery/Spee-s-Exc...dventure/Wiring

Also, the next day while cleanup was taking place, I had a circuit breaker trip on the house wiring. One of the ladies working outside came in and said there was a huge "pop." When I walked outside, there was an electrical cable immersed in mud with a big black spot where the short circuit occurred.

Tonight, walking up and down Suhkumvit, I seemed to notice more and more all of the temporary electrical cables strung across the sidewalk, some on dry cement, but also some sitting in little puddles of water.

I guess my point is to watch your feet when you are walking around. Also if there are electrical cables around your home or work, keep your eyes open for them. Wrong place at the wrong time could at least be a little scary, or at most be an injury-causing jolt.

Cheers,

Spee

PS. Thanks to RC and his wife and mum-in-law for taking the time to come to the house blessing ceremony. It was a blast! Many pix and a story to come when I have time.

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hi spee,ive just returned from phuket, my 8th trip, as u say the thai electrical system leaves a lot to be desired,especially the lack of grounding of anything,

its especially dangerous as they use 240 volts which is lethal, as opposed to 110 volts that some countrys use which wouldent hurt you much

,i dread to think how many people are electrocuted in los each year! just make sure you have a good quality rcd tripswitch fitted at the fuse box with a sensitivity of no higher than30 ma(milli-amps--.03 amp) at least that should afford some personal protection against electrocution!

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its especially dangerous as they use 240 volts which is lethal, as opposed to 110 volts that some countrys use which wouldent hurt you much

Ummm...It's not the voltage that is dangerous, it's the amperage.

Ski....

It is the current, BUT to get enough current you need the volts as well.

V/R = I

At my wedding someone plugged in a fan next to the head monk.

Several foreign friends thought he was plugging in the Sai Sin,

and would electocute all the monks!!! :o

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voltage carrys the current(amperage)the higher the voltage-the more amps will be carryed,and so-more lethal -

if you touch a 110 volt cable, you will only recieve about half the current than you would if you touched a 240 volt cable -i worked at a new marks and spencer store as an electrician last year(in uk)

2 guys were working in the mains room,the large armoured cable they were terminating became live--415 volts, killing one guy and seriously burning tother --not good!

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Wiring is very dodgey- I've seen arcs walking along the sidewalks (ones that you can find these days) in Pattaya. It looks like some tike has done the wiring on the poles...very surprised there isn't more accidental electrocutions with shoddy work like this just lying about. :o

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Wiring is very dodgey- I've seen arcs walking along the sidewalks (ones that you can find these days) in Pattaya. It looks like some tike has done the wiring on the poles...very surprised there isn't more accidental electrocutions with shoddy work like this just lying about.  :D

Ever seen a breaker switch in Isaan :D

Touch very carefully :o

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This reminds me of perhaps one of the worst jobs in Burma - the guy who has to hold the two nails wrapped in the respective ends of the cable for a power drill into the plug socket - the powerdrill in question was being used by the resident sparky!

Then again, i've seen some fantastic "fireworks" from my windows on soi23 when it rains and all the powerpoles go off on one..

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This reminds me of perhaps one of the worst jobs in Burma - the guy who has to hold the two nails wrapped in  the respective ends of the cable for a power drill into the plug socket - the powerdrill in question was being used by the resident sparky!

Then again, i've seen some fantastic "fireworks" from my windows on soi23 when it rains and all the powerpoles go off on one..

i stayed in the "white hotel" in pattaya a few years back ,the metal fire escape stairway on the outside, ran adjacent to the high voltage transformer!

the only way you could have got to the bottom, was to have squeezed past the 11-000volt cables ,killing yourself in the process no dought!

Edited by andy50
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... the only way you could have got to the bottom, was to have squeezed past the 11-000volt cables ,killing yourself in the process no dought!

I can't be sure, but isn't there a Tesco at On Nut BTS where, when you come out to go to the BTS you face the 10,000 volt power cables and there's a sign which says - not surprisingly - "Beware 10,000 Volts".

I suppose it could be an alternative to "sky-scraper diving" for the terminally depressed... :o

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hi spee,ive just returned from phuket, my 8th trip, as u say the thai electrical system leaves a lot to be desired,especially the lack of grounding of anything....

Did you go to Rawai? I'll try and get a picture of one of the local markets - they run the power cables across the road. Not above it - across it, on the tarmac :o. I guess the cables just have to withstand traffic for 3 or 4 hours. :D

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voltage carrys the current(amperage)the higher the voltage-the more amps will be carryed,and so-more lethal -

if you touch a 110 volt cable, you will only recieve about half the current than you would if you touched a 240 volt cable -i worked at a new marks and spencer store as an electrician last year(in uk)

2 guys were working in the mains room,the large armoured cable they were terminating became live--415 volts, killing one guy and seriously burning tother --not good!

Not true! The higher the voltage the less the ampage (voltage and current are inversely proportional).

Consider the formula - I = W/V. Amps = Watts over Volts.

If you have a 1,000 watt heater in los (highly unlikely unless in the mountains in December) and the voltage is 240, thus 1,000/240 = 4 amps roughly.

If you have the same heater in the States - 1,000/110v = about 10 amps, therefore half the voltage, double the ampage. But even when you have double the current in the States you're more likely to die from a fault on the los heater due to the voltage, or charge, being higher.

Another example would be a typical car battery able to dish out about 50amps but you certainly won't get killed even if you grab the positive and stand in a puddle of water because the charge is minimal.

But it's incorrect to think you will die, period, if you come into contact with high voltage because it also needs a substantial current (oomph) to be lethal. Insectocutors run at about 5,000v and inadvertently touching a bar on one of them (not recommended) will certainly give you a kick and will blacken your finger but more than likely won't be lethal, unless you have a foot in water.

With you're above example about the 415v pisser, you have a much greater chance of dying because it involves two or three phases (lives) to a machine and can draw exponentially more current. Even so, you won't necessarily be killed period, it all depends on the current it may be drawing and if it all goes through you or you just receive a taster.

Anyway, yes, Thai wiring is horrendous - seeing their sparkies (electricians) connecting cables when they're live, even when it's raining, beggars belief!

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But even when you have double the current in the States you're more likely to die from a fault on the los heater due to the voltage, or charge, being higher.

Another example would be a typical car battery able to dish out about 50amps but you certainly won't get killed even if you grab the positive and stand in a puddle of water because the charge is minimal.

Many examples of where a little knowledge can be a dangerous thing. Most of what you wrote is complete crapola.

Example: You are standing in a pool of water and touching the positive terminal of a car battery (i.e., you are effectively grounded).

Since your body is a conductor (i.e., mostly ionized water) and you are standing in water (presumably not de-ionized), the path of least resistance to ground (through your body) may only be presenting a load of a few ohms.

Assuming the car battery has sufficient charge, then simple math says 12vdc/\afewohms=severalamps, which is more than enough to be quite deadly, if it goes through the wrong part, namely the heart. Worse still, when the juice gets flowing, the muscles contract, making you unintentionally want to grab anything close. This can be another person or another conductor, neither of which make the situation any better.

Please be careful about giving advice if you aren't sure. Voltage or EMF when delivered through a low resistance path to ground (we're talking about through a person here), can easily provide enough current to be fatal (anything from a few milli-amps on up).

But back to the specifics of Thailand, the typical 220vac service there is just as dangerous as the US, the UK or anywhere else in the world, if not used correctly. It is the amps flowing through the body that kill.

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But even when you have double the current in the States you're more likely to die from a fault on the los heater due to the voltage, or charge, being higher.

Another example would be a typical car battery able to dish out about 50amps but you certainly won't get killed even if you grab the positive and stand in a puddle of water because the charge is minimal.

Many examples of where a little knowledge can be a dangerous thing. Most of what you wrote is complete crapola.

Example: You are standing in a pool of water and touching the positive terminal of a car battery (i.e., you are effectively grounded).

Since your body is a conductor (i.e., mostly ionized water) and you are standing in water (presumably not de-ionized), the path of least resistance to ground (through your body) may only be presenting a load of a few ohms.

Assuming the car battery has sufficient charge, then simple math says 12vdc/\afewohms=severalamps, which is more than enough to be quite deadly, if it goes through the wrong part, namely the heart. Worse still, when the juice gets flowing, the muscles contract, making you unintentionally want to grab anything close. This can be another person or another conductor, neither of which make the situation any better.

Please be careful about giving advice if you aren't sure. Voltage or EMF when delivered through a low resistance path to ground (we're talking about through a person here), can easily provide enough current to be fatal (anything from a few milli-amps on up).

But back to the specifics of Thailand, the typical 220vac service there is just as dangerous as the US, the UK or anywhere else in the world, if not used correctly. It is the amps flowing through the body that kill.

I don't know why I'm replying to this post because you obviously need to go back to school!

Most of what I wrote is crap? You condescending so and so!

Fact:

Voltage is inversely proportional to ampage.

Fact:

No matter what the ampage, electricity also needs considerable voltage to enable it to go through the skin and harm you! With the case of the car battery and if you're standing in a pool of water it wouldn't make any difference because the 12v in the battery will not go through the skin. How many times have you tightened the leads to your car battery and never felt a thing. You could even grab both electrodes and wouldn't feel it. Maybe if you attached one electrode to your bell-end and the other to your tongue you'd have problems.

The point I was making was an electrical supply needs sufficient voltage to be harmful.

You're getting there if you're just starting out in simple physics, Spee, but a little way to go yet.

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Not to start a p*ssing contest but ....

How many times have you tightened the leads to your car battery and never felt a thing.

You only feel something if you complete the circuit, which is why one takes care to never make electrical contact with the car chassis while handling the hot lead.

I will absolutely guarantee you that if you grab the hot side of the battery with one sweaty hand and place your other sweaty hand on the engine block, then you are going to be in for one very unpleasant surprise (assuming a normal battery with decent cold-cranking amps, of course).

The point I was making was an electrical supply needs sufficient voltage to be harmful.

Again, this is nonsense. You are confusing voltage with EMF (or eletro-motive force). They are related but are not the same.

Here is a simple example to the contrary of your point.

If you go into any major telephone or ISP central office or head end, all of the mission-critical gear will have a central 48VDC battery backup (in addition to a gennie and other things). In some CO's, I've seen batteries stacked high and deep enough to fill a 20ftx40ftx10ft room (that's 8000 cubic feet of batteries). Larger CO's will have even more.

While still only a 48VDC supply, this amount of batteries stacked in parallel, the battery farm is typically capable of providing literally hundreds of amps of current, quite easily enough to zap anyone into next week or the next life.

Relatively little voltage .... but gobs and gobs of EMF. Easily enough to kill or at least ruin your day if your body happens to complete a circuit with it.

You're getting there if you're just starting out in simple physics, Spee, but a little way to go yet.

I kept the physics simple on purpose. Not to pontificate, but given that I have an undergrad degree in physics and have done quite a bit of electrical design, I'm pretty sure that I know what I'm talking about.

Cheers ...

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Not to start a p*ssing contest but ....
How many times have you tightened the leads to your car battery and never felt a thing.

You only feel something if you complete the circuit, which is why one takes care to never make electrical contact with the car chassis while handling the hot lead.

I will absolutely guarantee you that if you grab the hot side of the battery with one sweaty hand and place your other sweaty hand on the engine block, then you are going to be in for one very unpleasant surprise (assuming a normal battery with decent cold-cranking amps, of course).

The point I was making was an electrical supply needs sufficient voltage to be harmful.

Again, this is nonsense. You are confusing voltage with EMF (or eletro-motive force). They are related but are not the same.

Here is a simple example to the contrary of your point.

If you go into any major telephone or ISP central office or head end, all of the mission-critical gear will have a central 48VDC battery backup (in addition to a gennie and other things). In some CO's, I've seen batteries stacked high and deep enough to fill a 20ftx40ftx10ft room (that's 8000 cubic feet of batteries). Larger CO's will have even more.

While still only a 48VDC supply, this amount of batteries stacked in parallel, the battery farm is typically capable of providing literally hundreds of amps of current, quite easily enough to zap anyone into next week or the next life.

Relatively little voltage .... but gobs and gobs of EMF. Easily enough to kill or at least ruin your day if your body happens to complete a circuit with it.

You're getting there if you're just starting out in simple physics, Spee, but a little way to go yet.

I kept the physics simple on purpose. Not to pontificate, but given that I have an undergrad degree in physics and have done quite a bit of electrical design, I'm pretty sure that I know what I'm talking about.

Cheers ...

Spee,I think you will find that Jackr is a sparky by trade with plenty of hands on experience and earns his living this way

I know who I would take my advise from. :o

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.... Jackr is a sparky by trade with plenty of hands on experience and earns his living this way

I know who I would take my advise from. :o

Whatever Chuchok .... I'm not trying to advise nor am I looking for "a forum street fight."

I know a lot of good sparkys too, but they're usually not electrical engineers. Doing basic house wiring is quite a bit different than desiging and installing large electrical systems (AC, DC, various worldwide electrical standards, etc.) or having a deeper theoretical background.

No disrespect to Jackr was intended. I just didn't agree with some of what he called "facts."

Mai bpen rai ... :D

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I touched an electrified cattle fence once. Once was enough! My left foot stamped into the ground harder than I could possibly have made it using my brain and I jump up in the air quite a way. :o

I also once tried to check a 440 volt power source, but the meter I was using was set to measure "amps". There was a big bang and most of the probes vaporised. I didn't feel a thing because the probes were insulated. :D

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I touched an electrified cattle fence once. Once was enough! My left foot stamped into the ground harder than I could possibly have made it using my brain and I jump up in the air quite a way. :o

A very wise radio engineer once told me about electricity:

"The only true ground is the one below your feet."

Hence, one of the original motives behind this thread.

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Again, this is nonsense. You are confusing voltage with EMF (or eletro-motive force). They are related but are not the same.

Here is a simple example to the contrary of your point.

If you go into any major telephone or ISP central office or head end, all of the mission-critical gear will have a central 48VDC battery backup (in addition to a gennie and other things). In some CO's, I've seen batteries stacked high and deep enough to fill a 20ftx40ftx10ft room (that's 8000 cubic feet of batteries). Larger CO's will have even more.

While still only a 48VDC supply, this amount of batteries stacked in parallel, the battery farm is typically capable of providing literally hundreds of amps of current, quite easily enough to zap anyone into next week or the next life.

Relatively little voltage .... but gobs and gobs of EMF. Easily enough to kill or at least ruin your day if your body happens to complete a circuit with it.

The difference the number of batteries makes is internal resistance. You get the maximum current through the load, if you are varying its resistance, when the load is equal to the (composite) battery's internal resistance. 8000 cubic feet of constituent batteries will have piffling internal resistance, which is one way of explaining how it can supply a large current. (An equivalent explanation is to note that each constituent battery is only supplying a small current.)

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voltage carrys the current(amperage)the higher the voltage-the more amps will be carryed,and so-more lethal -

if you touch a 110 volt cable, you will only recieve about half the current than you would if you touched a 240 volt cable -i worked at a new marks and spencer store as an electrician last year(in uk)

2 guys were working in the mains room,the large armoured cable they were terminating became live--415 volts, killing one guy and seriously burning tother --not good!

Not true! The higher the voltage the less the ampage (voltage and current are inversely proportional).

Consider the formula - I = W/V. Amps = Watts over Volts.

If you have a 1,000 watt heater in los (highly unlikely unless in the mountains in December) and the voltage is 240, thus 1,000/240 = 4 amps roughly.

If you have the same heater in the States - 1,000/110v = about 10 amps, therefore half the voltage, double the ampage. But even when you have double the current in the States you're more likely to die from a fault on the los heater due to the voltage, or charge, being higher.

Another example would be a typical car battery able to dish out about 50amps but you certainly won't get killed even if you grab the positive and stand in a puddle of water because the charge is minimal.

But it's incorrect to think you will die, period, if you come into contact with high voltage because it also needs a substantial current (oomph) to be lethal. Insectocutors run at about 5,000v and inadvertently touching a bar on one of them (not recommended) will certainly give you a kick and will blacken your finger but more than likely won't be lethal, unless you have a foot in water.

With you're above example about the 415v pisser, you have a much greater chance of dying because it involves two or three phases (lives) to a machine and can draw exponentially more current. Even so, you won't necessarily be killed period, it all depends on the current it may be drawing and if it all goes through you or you just receive a taster.

Anyway, yes, Thai wiring is horrendous - seeing their sparkies (electricians) connecting cables when they're live, even when it's raining, beggars belief!

----------------------------------------------------------------------------------------------

hi jackr, i agree with you ,you must have misunderstood my post ,im not too good at explaining myself! the higher the voltage is the higher the amount of current will be, passing through the person on thr recieving end -as for feeling a shock from a 12 volr car battery --ridiculous--the voltage is way to low to carry enough current through your body-even the 45 volts mentioned is still safe to touch with no flow of current through the body

in the iee regs (uk)any voltage up to 55 volts it considered safe

Edited by andy50
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as for feeling a shock from a 12 volr car battery --ridiculous--the voltage is way to low to carry enough current through your body

Bordering on off-topic overkill here but .....

You're trying to tell me that a car or truck battery capable of delivering several hundred cold-cranking amps (that's several hundred amps for 30 continuous seconds, at zero degrees farenheit, without having the voltage drop below 10.5vdc), does not pose a potentially lethal shock hazard if your body completes a circuit with it?

Okay ....seems far fetched ... but if you say so .... then ... well ...

(maybe I have a chance of becoming a world class marathoner after all)

LOL :o

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Any of you experts want to fix one of the lights in my house in Phuket?.The glass melted & left the metal in the socket. Don't mind simple electrics in the UK but I don't do electrics in Thailand, not even for a light bulb!!! :o

I have to. Every bloomin' day! My screw-in bulbs are forever going off and I have to get the step-ladder out and give them a tweak - usually unscrew a little and then screw back up. And sometimes the thin metal thread inside comes away with the bulb, so I have to take the whole thing out of the ceiling and fiddle with it to get the metal thread back inside.

If anyone else has this problem and knows a good way for a permanent fix, I'd love to know. The best idea I've had so far - albeit untried - is to solder leads to the bulb and connect it to the power supply manually using a connector block.

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This may be of use:

http://www.chclibrary.org/micromed/00046420.html

The severity of injury depends on the current's pressure (voltage), the amount of current (amperage), the type of current (direct vs. alternating), the body's resistance to the current, the current's path through the body, and how long the body remains in contact with the current. The interplay of these factors can produce effects ranging from barely noticeable tingling to instant death; every part of the body is vulnerable. Although the severity of injury is determined primarily by the voltage, low voltage can be just as dangerous as high voltage under the right circumstances. People have been killed by shocks of just 50 volts.
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