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> Wiring guide : 3 color wire (green, blue,black), Which one neutral, live and earth

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ceo684
post Jun 22 2020, 02:44 PM

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QUOTE(JasonTheGreat @ Jun 22 2020, 02:27 PM)
Hi. Can you advice on this.
Why Live is connected to Neutral and Neutral to Live?
Thanks
*
Because, humans make mistakes.
Just like traffic light, red is stop, green is go, but millions of people still beat red light.

Colour code supposed to be standardise but theres a lot of faux electrician out there simply connect using any colour. And it gets more complicated if its looping (ie not direct DB because if you change it at one end it might still be wrong halfway- need to trace back that circuit whether it is just that one circuit or others also affected.

If you can confirm using test pen that the live is the hot one, turn off whole DB box, check again and confirm with working test pen that all are off already, then swap the bottom pair (clean wires without paint) correctly, then it should be OK.

That's why rule #1 always assume previous faux electrician is an idiota, test to confirm your test pen is working, test test test before touching any wires, NEVER WORK HOT (live). Always assume the wire is hot and make sure to confirm the DB box is all off as well, even after lunch break always assume someone has turned it on, test test test, and colours are installed by colour blind previous faux electrician.

This post has been edited by ceo684: Jun 22 2020, 02:51 PM
ceo684
post Jun 22 2020, 02:48 PM

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In the wall, stiff wire, usually it is
Live - Red Yellow Blue sometimes white, depending on phase
Neutral - Black (common neutral)
Earth - Green

Outside of wall - to fitting/flexible cable, usually it is
Live - Red/Brown
Neutral - Blue
Earth - Yellow/Green stripes or Green

This post has been edited by ceo684: Jun 22 2020, 02:48 PM
ceo684
post Dec 10 2020, 11:54 PM

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QUOTE(williamchiew @ Dec 10 2020, 05:59 PM)
Hi all,

I have a noob questions to ask for help. I'm trying to figure out whether I can loop a power point for use like laptop or charge phone from existing light switch.

Is that possible to add that? Or still need wiring like neutral and earth.
Is a bit hard for me to get the neutral and earth wiring as it's all sealed inside a partition wall.

Thanks in advance.

user posted image

user posted image

user posted image
*
Not possible. This L circuit at the switch doesn't provide return neutral and earth required for 13A socket there.
The lights' N is connected only up to/at the light point.
ceo684
post Jan 7 2021, 10:55 PM

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QUOTE(Agent 45 @ Jan 7 2021, 04:48 PM)
[attachmentid=10750504]
Hi, how to connect this two core copper wire to the plug? i assume just connect either one of the copper wire to Live and Neutral, correct?
*
Depends on what is on the other end devil.gif if its a lamp (based on the thin wiring) then either one will work.
ceo684
post May 30 2021, 03:09 PM

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QUOTE(jskhoo @ May 30 2021, 11:50 AM)
Is it?  doh.gif
What should be the power rating I need? Any suggestion of which Smart switch I would need for a storage water heater please?

Thank you
*
3kw water heater need a 20A DP (double pole L+N);
Else u need to wire up a contactor instead if you want to use original switch. A contactor allows a kancil to control the operation of a trailer load.
ceo684
post Jun 1 2021, 08:58 PM

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QUOTE(jskhoo @ Jun 1 2021, 08:43 PM)
Forgot to ask, could anyone help me identify which wire is Live(IN), Live(OUT), Neutral?

user posted image

Thank you
*
Blue LINE (always ON regardless)
and the black to its 3 o clock is N

Red LOAD (switched ON/OFF) (based on LED).
and the black to red 3 o cllck is N

Confirm with test pen or multimeter because the previous installer is color blind.
Never trust the colour. Bangla tarak wireman cert one.

This post has been edited by ceo684: Jun 1 2021, 10:05 PM
ceo684
post Jan 30 2022, 05:14 PM

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QUOTE(EvOliver @ Jan 30 2022, 04:57 PM)
Right. So in this case, can't really assume Black is usual Live. Have to really verify, either by reference connection, or by test pen, to be sure.
*
Generally in MY the code colours black is never L regardless flexicord or stiff (solid stranded) wire.

However there's a lot of champion never follow proper colour code. Assume installer is colour blind and test to be sure.

⚠️ There is a possibility idiota installed L and N terbalik. Pls test to be sure.

IN-WALL 230V wiring colour code typically
L red yellow blue, sometimes even white 🤦‍♀️
N is black
E is green

This post has been edited by ceo684: Jan 30 2022, 06:49 PM
ceo684
post Jan 30 2022, 05:17 PM

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QUOTE(IMF2025 @ Jan 30 2022, 03:55 PM)
Black is usually live
Blue is nuetral
*
Ini terbalik. Black is usually neutral in MY. Overseas code lain cerita.
ceo684
post Jan 31 2022, 12:42 AM

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QUOTE(EvOliver @ Jan 30 2022, 10:19 PM)
Actually, I'm looking for a standardised spec for Malaysia power line colour code. Everyone should follow the same standard to avoid confusion nor misunderstanding.
*
It's in MS1979 spec and ST guidelines. Item 5.5


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ceo684
post Jan 31 2022, 09:44 PM

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QUOTE(louyeh @ Jan 31 2022, 04:37 PM)
Electrical wire colour code is only reliable if its practiced at the main DB first.

Test pen can't differentiate Earth vs Neutral.

Multimeter is the better tool.

E & L = 230VAC
E & N = As close to 0VAC as possible, 1-2VAC is fine. Anything higher indicates improper wiring/installation
L & N = 230VAC

Majority of electricians rely on test pen. The minorities don't bother to use one as they don't understand E & N difference.
*
Sometimes with champion faux electrician the code is only followed up to the first light.. then switch relocated + new lights added in same line due to plaster ceiling what you see at the switch and other lights will surprise you.
ceo684
post Feb 2 2022, 12:49 AM

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QUOTE(EvOliver @ Feb 2 2022, 12:26 AM)
How to differentiate N and E by DMM?
*
Easy, only the N will have current when load is running and E show 0A.


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