Which side of an electrical outlet should be Neutral?

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Alchai
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Re: Which side of an electrical outlet should be Neutral?

Post by Alchai » February 19, 2011, 4:28 pm

fdimike wrote:If the plug is polarzed it will have 1 blade wider than the other
I haver never seen a polarised plug in Thailand. Maybe someone here can explain a little better what one should do for good safety praxis in Thailand.



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Re: Which side of an electrical outlet should be Neutral?

Post by jimboLV » February 19, 2011, 5:29 pm

I just bought a Samsung refrigerator , 9 cf so not a 'lil' feller'. Not only does it NOT have a grounded plug, but the two pronged plug is not even polarized! Yet the instruction manual goes on and on about how it should be grounded for safety. :? Granted the English instruction manual downloaded was from Malaysia, as the Thai refrigerators only have instructions in Thai, but it appears to be the same model. Could it be that the models sold in Thailand are double insulated, thus not needing grounding? Doubtful. We also bought a Samsung Wash machine, which does have a three pronged plug. I then checked all the appliances and extension cords in the house, and none of those without grounded plugs were polarized. So you can bet that if I'm going to work on anything electrical around the house, the power will be shut off at the main.

We just moved into our newly constructed home and all the outlets are grounded with the common (neutral) on the left. I don't know if this is standard practice since I told the electrician to do it that way and that I would be checking it. I did check and they were all wired correctly. Unlike a new home I bought in the US where I found two outlets where the ground wasn't connected and one where the polarity was wrong.

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Re: Which side of an electrical outlet should be Neutral?

Post by fdimike » February 19, 2011, 7:13 pm

I have a large Hitachi refrigerator without a 3 prong or polarized plug. I solved the problem by changing the plug to a 3 prong version. A good rule of thumb in determining which wire is supposed to be hot (positive) and which is neutral is to look at the wire. If the wire is flat with two seperate lines look for some printing on the wire. The line with the printing should be the neutral line. I then added a new ground line securing it with zip ties along the way from the refrigerator to the plug. The fix works like a champ.

Washing machines are typically more dangerous then refrigerators as you are mixing electricty with water. It's really essential the washer be grounded to avoid receiving an unnecessary shock when reaching into the washer in bare feet.

Here's a great web site for all to read about electricity here in Thailand:

http://www.thailandguru.com/electricity ... iland.html

Hope this helps.

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 1, 2011, 1:13 pm

It doesn't make any difference which side is active or neutral. In Aus the only reason they have active on a selected side is because a switch is used in the active conductor and if wired ar..about then the switch is operating in the neutral which is illegal here. Obviously because they want the switch to cut supply.

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Re: Which side of an electrical outlet should be Neutral?

Post by fdimike » March 1, 2011, 1:28 pm

Apparently AU doesn't have as tough an electrical code as the US. There is a logical reason for keeping all the hot (active/positive) lines aligned. Maybe a re-read of the website might make it clearer.

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 1, 2011, 1:32 pm

If you read my reply correctly then you will see I stated that in Aus it is illegal to have reversed connections. My point was that in Thailand there is no switch on the majority of outlets AND most outlets can have the plugs inserted either way anyhow.

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Re: Which side of an electrical outlet should be Neutral?

Post by fdimike » March 1, 2011, 9:26 pm

Bluejets
To be truthful I couldn't quite make out what you were talking about in your previous post. I can only gather that I misinterpeted what you said and for that I apologize. If the building is built according to the Thai electrical code (LOL) which has been in effect for at least 5 years now then all electrical wiring is SUPPOSED to be 3 wire. This is what I was told by the electric company officials when we built our house 5 years ago. If that is the case then it would also be wise to properly install 3 prong plugs on ones appliances in order to take advantage of the safety features offered by a 3 wire system. It would then be really wise to make sure the outlet is wired correctly. FYI: 3 prong plugs to retrofit your appliances are available at Tool Pro Plus, Home Pro & I believe Global House as well as several major electrical outlets downtown.
While you are right that most 2 prong plugs here in Thailand can be inserted either way it would be a good idea to try and determine just which wire of the appliance is the positive and plug it into the outlet accordingly. Better yet just clip the 2 prong plug off, run a seperate ground wire from the appliance alongside the original electrical cord and then install a 3 prong plug. You can easily zip tie the ground line to the original electrical cord to keep things neat. The obvious ultimate solution would be to replace the 2 wire cord with a 3 wire and be done with it.

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 2, 2011, 5:53 am

True...three wire system needs to be more enforced. Safety cut too.
I spoke with a so-called lecky there only a couple of weeks ago and to my surprise he had been serching for information on how to wire with m.e.n system. So there appears to be some degree of interest. Perhaps the fact that I explained how his business would invariably increase especially with the farang population if he used the system and had knowledge of the theory behind it.
Apart from that, it still makes no difference in theory whether the active conductor say for arguments sake in a frig, is connected from one outlet pin through a motor then through the thermostat and back to the neutral on the other outlet pin or in the reverse direction. Everything will work just fine .AC current and voltage reverses every half cycle so this is not in question.
What is important is the active conductor is cut by any isolating switch that is present. Thailand doesn't seem to use isolator switches much from what I have seen.Thermostat would be included here and would be originally as well, but people fit a new plug, get the connection ar..about and then things are back to TIT.
When you use a 3 pin outlet from western countries, the switch is incorporated in the unit and correct polarity of the connection must be adhered to so the active is cut through the switch. (not the neutral) Again things will still work if connected back to front, but when you turn off the appliance, the active is still present and can be dangerous under certain conditions. Of course the earth pin must go to the correct pin, I think for most people this goes without saying.

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Re: Which side of an electrical outlet should be Neutral?

Post by Bandung_Dero » March 2, 2011, 6:05 am

bluejets wrote:True...three wire system needs to be more enforced. Safety cut too.
I spoke with a so-called lecky there only a couple of weeks ago and to my surprise he had been serching for information on how to wire with m.e.n system. So there appears to be some degree of interest---
So long as he is only showing an interest and does NOT try it. MEN is a system that only works safely on an entire distribution circuit. Here in our village and I believe most of Thailand the neutral is only tied to Earth at the local stepdown transformer 'Star' point.

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 2, 2011, 9:29 am

Yes. And your point being.....???
This is the start of the m.e.n system requirements.
From here the main earth is connected to the main neutral in the switchboard for proper operation. This is why it is called multiple earth neutral.
There seems to be mass confusion out there as to just what protects what. I hear so much talk about running earth wires but no one understands the system and each comment seems to just add to the confusion.
The Main earth electrode is to maintain neutral conductor voltage at ground potential, without this the supply begins to "float" above ground.
Yes, earth wiring from the outlet carries any fault current but if this is only connected to a stake in the ground, the fault current tries to flow through the soil and back to the earth stake at the transformer. (high impedence to fault current and therefore danger to anyone connected to it just the same)When the main earth is connected to the main neutral, fault current flows from the fault in the outlet, through the earth wire from the outlet to the main earth and from the main earth to the main neutral and then back to the star point of the transformer. So completing a low impedence path to the fault. This is what operates circuit breakers in the way they were designed also.

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Re: Which side of an electrical outlet should be Neutral?

Post by Bandung_Dero » March 2, 2011, 4:00 pm

bluejets wrote:Yes. And your point being.....???
This is the start of the m.e.n system requirements.
From here the main earth is connected to the main neutral in the switchboard for proper operation. This is why it is called multiple earth neutral.
There seems to be mass confusion out there as to just what protects what. I hear so much talk about running earth wires but no one understands the system and each comment seems to just add to the confusion.
The Main earth electrode is to maintain neutral conductor voltage at ground potential, without this the supply begins to "float" above ground.........
My point is I will not bond my Earthing system to neutral as we're located near the end of our distribution network and I've seen Neutral floating as high as 50 VAC above Earth and far be it from me to be the only consumer to try to drag it down, in fact I installed dual pole cct breakers for that reason.

What happens if, for some reason, I loose my connection to the Earth stakes? I'll tell you what, all of a sudden my PC case (for example) is alive. THAT'S MY POINT. [-X

I will admit the Power Authority did replace our transformer 2 years ago after it blew up and the float dropped considerably to safe levels but I still will not initiate an MEN system. Leave it to them.

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 2, 2011, 5:29 pm

Well as usual, another one with a half educated idea of what is and what isn't.
You have no idea of what you are talking about.
To answer your self answered question correctly, i.e. what happens if you loose you earth connection to the earth stake, under an m.e.n. system the voltage will begin to float above ground, the level being dependant on how far you are from the earth point of the transformer. Your PC case will NOT become live to the point that you seem to suggest would electrocute someone.
As you just said, a condition you have now already and probably a cause of potential problems.
What will happen if you do NOT have an m.e.n. system, under fault conditions your pc case will definetely have a high level voltage on it even if it is not the faulty appliance. AND your double pole breaker won't be worth a crumpet at protecting you either because it relies on a low impedence path back to the transformer star point to be within it's designed trip parameters and including trip time. Hopefully you have a safety cut.
BTW as far as I am aware, supply authorities in Thailand could not give a flying f... what happens beyond their equipment and they are not responsible for your installation so if you are waiting for " leave it to them" it will never happen.

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Re: Which side of an electrical outlet should be Neutral?

Post by Bandung_Dero » March 3, 2011, 6:35 am

bluejets wrote:Well as usual, another one with a half educated idea of what is and what isn't.
You have no idea of what you are talking about.
AND your double pole breaker won't be worth a crumpet at protecting you either because it relies on a low impedence path back to the transformer star point to be within it's designed trip parameters and including trip time. Hopefully you have a safety cut.
And I have no idea what I'm talking about!!!! Do you know WHAT a double pole circuit breaker is??? It is NOT an RCD or ELCB it's exactly what it says. Isolates BOTH Active and Neutral in an overload condition or when isolation is required for works. A floating Neutral is then no problem.

Get educated or at least get YOUR facts in order!!!

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 4, 2011, 10:29 am

For any circuit breaker to work as designed, be it single pole, double pole, three pole or four pole, the circuit must have low impedence. When you try to push an earth fault current through the soil to transformer star point, this is high impedence and the circuit breaker will not operate as designed. This will in most cases mean it will never trip.

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Re: Which side of an electrical outlet should be Neutral?

Post by Bandung_Dero » March 4, 2011, 7:40 pm

Oh my! You still do not have it do you, and even after my PM. To the Expats reading this BS please ignore and treat the so called expert ( we all know what one of those are) as inexperienced, though be it half educated novice. He will have to gain another 20 years experience to even get close to understand what the facts are.

For our learned friend a circuit breaker is NOT a fault condition isolator but rather than circuit protection device primarily to stop the wiring from burning in an overload or short circuit condition, the circuit breaker is there to protect the CABLE, NOT the consumer. It's rating is designed to reflect the distribution cable size: typical lighting on 1.5 mm2 will use 15 amp and power on 2.5mm2 will use 20 Amp.

So where it comes to protecting the consumer we rely on devices such as an RCD (Residual Current Device) also known as a 'Safety Cut' here in Thailand or in a western country where the MEN installation is used the ELCP (Earth Leakage Circuit Breaker) is more common.

Now when it comes to the number of poles a single pole breaker of which 90 % of you see in your distribution panel only trips Active (providing the average ***** Thai electrician has wired your home correctly) and if you use it for isolation to do maintenance on a particular circuit BE CAREFUL.

I used a Dual (two pole) breaker isolating both active and neutral. Not only gives me cable protection BUT also isolates both Active and Neutral if I need to work on the circuit.

You Mr BlueJets need to get some serious experience if you wish to earn the BIG dollars available in the oil and gas or associated industries any time in the future, and what ever you do keep away from any of my works.

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 5, 2011, 12:23 pm

You quote that (among other things just as questionable)
"a circuit breaker is not a fault condition isolator but rather a circuit protection device"This is the same thing so I fail to see the point.
Surely if the consumer were of such little consequence then why bother with any protection.
Just goes to show how little you know.

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Re: Which side of an electrical outlet should be Neutral?

Post by fdimike » March 5, 2011, 12:56 pm

Bandung & Blue,

You both seem to have much more knowledge about any of this stuff than the rest of us mere mortals. May I suggest a truce be called and maybe one (or both) of you can try to explain what you are saying in common english. By common english I mean everyday english so the rest of us who are interested can comprehend what you are saying. I have never heard some of the electrical terms you guys are using. I understand how to wire an outlet/plug and have a basic knowledge of just how electricity in the home SHOULD work. I also understand that there is an electrical code here in Thailand but no one to enforce it like we have in the US or Europe/Australia.
I think you guys could educate a lot of us out here as to the correct way to install electrical wiring in ones home. So how about it? No more fighting, but a lot more educating.

Just my 50 Satang worth.

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Re: Which side of an electrical outlet should be Neutral?

Post by RLTrader » March 5, 2011, 7:04 pm

Ok, Mike I will nominate you for the peace prize.

I just love how someone on the internet gets to be an expert in anything with no questions being asked. Like some of these expert Home Builders. Some don't even live here, but they still know everything about building here.

Just for chuckles I googled the difference Mr. Blue and got the below link. Goggle is your friend, Mr. Blue. :lol:


http://www.allinterview.com/showanswers/81651.html

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Re: Which side of an electrical outlet should be Neutral?

Post by Bandung_Dero » March 6, 2011, 8:00 pm

bluejets wrote:You quote that (among other things just as questionable)
"a circuit breaker is not a fault condition isolator but rather a circuit protection device"This is the same thing so I fail to see the point.
Surely if the consumer were of such little consequence then why bother with any protection.
Just goes to show how little you know.
You effin dlckhead! If you can't distinguish between the two WTF are you trying to confuse others on this site. I dare you to take your ideas and resume to ANY heavy industry or oil and gas employer asking for a job. In fact take it to your local 'House Basher' and see how you go!

You continue to dig your hole and believe you me I'll bury you!

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Re: Which side of an electrical outlet should be Neutral?

Post by bluejets » March 7, 2011, 10:36 am

mmmm....nice
See diagram and text for conformation of my explanation.
Attachments
MenSys.jpg

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