Outlet wrongly wired? Neutral Ground Reversed

[jojothai]

2 hours ago, bankruatsteve said:

Twist and tape does not mean wrong if done properly.  Thais generally make a connection that is almost impossible to loosen.  That is what is wanted in a connection.  Almost as important is that all connection need to be in an enclosure (box).  Wire nuts generally available in Thailand are c_r_a_p.  Twist and tape is preferred over those.  I prefer crimp connectors but there you go.

I have seen twist and tapes that get done properly, but I would say that more than half are not. and I often find they are in risky places close to metal, eg most often with down lighting fittings.

There are the plastic twist connectors shown below, in various sizes for different size of wire. Some are good and the wire inside holds well, some just dont seem to be well designed / tested and if you pull its easy for the wire to come out. 

If you get some then test how easy the wire can pull out. and so that you know how to get the wire in properly.

when I have used them I normally also put some tape around them (of the same color as wire type),

 

I generally use the the plastic terminal style connectors that are used in the UK, see  below. I look for a branded name and dont buy the cheapest. I have seen some a few times that have degraded over time and the plastic just falls off as soon as you put a screwdriver in. The problem with these can be the practicality of getting them onto existing wiring  when there is not much room to get your hand(s) and the screwdriver in to tighten them.

 

Edited July 21, 2020 by jojothai
add info

[Crossy]

I've never been a fan of twist-n-tape or wire nuts for that matter (not permitted in the UK). But a linemans splice, possibly soldered as well and sheathed in heatshrink (adhesive lined if there's the possibilty of damp) is going nowhere.

 

The Wago push or lever connectors are a quick and easy alternative.

[Metropolitian]

7 hours ago, Polarizing said:

I have just opened up a socket and found out that the the green wire is connected to N and the white wire is connected to the Earth symbol. Blue is in L, everywhere in my home blue is the live wire.
Am I safe to assume neutral and ground are reversed? Or should I do some additional tests?

First I have checked your CU, a split unit that is.

The wiring is very neat, only the coloring... well.. not according the standard but we will leave it at that.

The installers even used a nice coloring ring at the mains input.  In your location Blue is hot and high as the sky and White is the neutral, Green is the right one and is Earth.

One thing about the wiring in your CU, I do see -one- brown wire, it is used in your case as neutral wire, do you know where it goes? Has it a right 'marking' at the end point? (white tape or marking 'N' )

 

Now your outlet.  If the green wire is connected to the N and white is connected to the earth symbol. Then yes, according to the setup in your CU, this outlet is wrongly, not badly, connected. I can wildly assume that this socket is on the 'unprotected' side of the CU. If this socket was on the RCBO protected side, then it would trip as there would then be imbalance between the L and N at the RCBO.

 

Have you checked other outlets and their wiring?

[Polarizing]

10 hours ago, Metropolitian said:

First I have checked your CU, a split unit that is.

The wiring is very neat, only the coloring... well.. not according the standard but we will leave it at that.

The installers even used a nice coloring ring at the mains input.  In your location Blue is hot and high as the sky and White is the neutral, Green is the right one and is Earth.

One thing about the wiring in your CU, I do see -one- brown wire, it is used in your case as neutral wire, do you know where it goes? Has it a right 'marking' at the end point? (white tape or marking 'N' )

 

Now your outlet.  If the green wire is connected to the N and white is connected to the earth symbol. Then yes, according to the setup in your CU, this outlet is wrongly, not badly, connected. I can wildly assume that this socket is on the 'unprotected' side of the CU. If this socket was on the RCBO protected side, then it would trip as there would then be imbalance between the L and N at the RCBO.

 

Have you checked other outlets and their wiring?

Thanks for the summary, I have no idea about the brown wire, wild guess would be a newly installed neutral from a smart switch, but I don't think so actually since the installer of that neutral doesn't look like he had a brown wire. Does it matter much?

I need to check other outlets and their wiring ofcourse, but can only do so after I know how to do this one. Most outlets are connected with white wire so I will get it checked by removing the neutral from the busbar and test the voltage from the outlets.

[Polarizing]

14 hours ago, lopburi3 said:

These copies (Wago is brand name) are very reasonable price now (a newer version is available) and make a much better connection and are just about foolproof.  

 

 

Do you know what these 3 conductors (3 holes) are used for? Do I need them and if so, I want to read more about them. Where can I do so?
Or do I only need the the two holed version? 

[Metropolitian]

8 minutes ago, Polarizing said:

Do you know what these 3 conductors (3 holes) are used for? Do I need them and if so, I want to read more about them. Where can I do so?
Or do I only need the the two holed version? 

Wago is a brand, but they were the 'inventors' of the standard of the springclamps

 

https://en.wikipedia.org/wiki/WAGO_Kontakttechnik

 

It's effectively a products where you can connect wires together (even single cores and stranded wires) and without using screws.

 

One block connects all wires together.  You need separate blocks for other wires.

 

 

The two hole versions are useful for 'connecting' stranded wires with single core wires.

Three hole versions for taps and four and more for central bindings.

They are mostly used in conduit boxes.

 

 

 

 

 

The wireclamps with the orange lever are a new thing.

I used to work with grey Wagos , later they came in orange colors.

 

 

 

[lopburi3]

5 hours ago, Polarizing said:

Do you know what these 3 conductors (3 holes) are used for? Do I need them and if so, I want to read more about them. Where can I do so?
Or do I only need the the two holed version? 

The two hole connects a wire and the 3 and above are used for multi connections (all are connected together).  These are easy to use and connection never gets loose - and also easy to remove to change things.  The clone is just as good as the original in tests I have seen and can say wires are not coming out if you put them in fully.

 

[mahjongguy]

I'm a fan of wire nuts; I think they can be very effective if they are used with a bit of care. When connecting a stranded wire to non-stranded, it's just a matter of putting a slight kink in the stiffer wire so that the wire nut can screw on to it.

 

But, I like these Wago levered connectors. They appear to be somewhat one-size-fits-all. Is that right? Anyone got a link to a Thai source for the clones?

[tonray]

On 7/21/2020 at 8:41 AM, Polarizing said:

By the way I bought a very cheap, around 130 thb multimeter at tesco lotus before, which I regretted (because i thought it might not be safe) and never used. You think its safe to use or just throw it away hahaha

I have one of those too...it's safe..I use it often

[lopburi3]

10 minutes ago, mahjongguy said:

I'm a fan of wire nuts; I think they can be very effective if they are used with a bit of care. When connecting a stranded wire to non-stranded, it's just a matter of putting a slight kink in the stiffer wire so that the wire nut can screw on to it.

 

But, I like these Wago levered connectors. They appear to be somewhat one-size-fits-all. Is that right? Anyone got a link to a Thai source for the clones?

I buy from Lazada and Shopee

https://www.lazada.co.th/products/10-pieces-1lot-mini-fast-universal-compact-wire-wiring-wago-car-connector-set-conductor-terminal-block-solar-energy-easy-quick-i884658295-s1779714645.html?

https://shopee.co.th/search?keyword=wago

[sometimewoodworker]

7 minutes ago, tonray said:

I have one of those too...it's safe..I use it often

Those testers can fail over time, so like most equipment it needs to be checked periodically.

[tonray]

5 minutes ago, sometimewoodworker said:

Those testers can fail over time, so like most equipment it needs to be checked periodically.

Yes...but safety (since I'm only ever touching insulated leads is not an issue. There is a fuse that will melt so the device won't melt or explode in flames.

Edited July 22, 2020 by tonray

[sometimewoodworker]

20 minutes ago, tonray said:

Yes...but safety (since I'm only ever touching insulated leads is not an issue. There is a fuse that will melt so the device won't melt or explode in flames.

The test screwdriver certainly is unlikely to melt or explode in flames however, since to actually use the test function you have to touch a live wire one failure mode will allow the full current to pass to you. So safety certainly is an issue.

[tonray]

12 minutes ago, sometimewoodworker said:

touch a live wire one failure mode will allow the full current to pass to you

Insulated handles would seem to protect me...but maybe rubber/plastic is a conductor now ?

[sometimewoodworker]

1 hour ago, tonray said:

Insulated handles would seem to protect me...but maybe rubber/plastic is a conductor now ?

You missed that I talked about the dangers of a test screwdriver or you clearly don’t understand how a test screwdriver functions. It has a resistor and a neon, it requires you to complete the circuit by touching the metal end cap. One failure mode for a resistor is a dead short and since a neon lamp is also has an extremely low resistance at over about 80V you can get a full mains voltage shock which can kill.

Edited July 22, 2020 by sometimewoodworker

[Metropolitian]

2 hours ago, sometimewoodworker said:

You missed that I talked about the dangers of a test screwdriver or you clearly don’t understand how a test screwdriver functions. It has a resistor and a neon, it requires you to complete the circuit by touching the metal end cap. One failure mode for a resistor is a dead short and since a neon lamp is also has an extremely low resistance at over about 80V you can get a full mains voltage shock which can kill.

The percentage of failing resistor that goes dead short is very small near nihil.

They can short, but on high voltage and arcing caused by the loss of insulation (cracks).

 

I wouldn't worry that much about a resistor that fails that way.

More concern are needed with capacitors which really can short when they fail.

 

Another story is with overheated resistors, when they burn the material inside the resistor can carbonize and then conduct electricity.

In a test screwdriver the change of that to be happen is also zero.

[Metropolitian]

4 minutes ago, Metropolitian said:

the dangers of a test screwdriver

I've encountered a 'failed' test screwdriver where the resistor + neon combination was turned around and the spring bypassing the resistor  (which was in fact inside the spring) .

Yes that one was not good

[Crossy]

Like all tools neon drivers need to be treated with respect and like most tools they have the potential to hurt you. Don't leave it banging around in the toolbox (we all do), chuck it when it gets damaged (they are cheap).

 

Many of us have heard the story of the apprentice sparks who dropped one in a puddle and then replaced it in his boss' toolbox. The boss was not amused when he used it!!

 

After an "incident" many years ago with a 12V tester that I thought was a neon (that stung somewhat). I always test the neon first on a live terminal with a very ginger dab of the finger on the end, if I don't die and the neon lights up we're good to go.

 

[Metropolitian]

Used to have a voltage tester in the eighties/nineties.

Styled like the one in the picture but with bigger insulation, neon lights and range up to 1000V.

 

The screwdriver with neon was always in the pocket of my overall along with pen and markers ????

Only used the screwdriver for tightening little screws (telecom wires).

[Metropolitian]

12 minutes ago, Crossy said:

with a very ginger dab of the finger on the end

and try not lick it before like with turning pages ????