Which neutral to use

RetroRabbit

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Oct 3, 2019
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Hey guys

Hoping you can help, I was looking at getting this smart switch. I just opened up my switch and saw something interesting, there are 3 live (red) 3 neutral (black) and a copper cable.

So it seems two live and two neutral come in. The two reds are on the in of the switch with the third one being on the exit. But all three the neutral wires are shorted together.

So if all three neutrals are shorted, do I put all three into the neutral of the switch or only one of the ones coming from one of the red wires (input not outgoing)?

Hope that makes sense.
 

SauRoNZA

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Don’t believe just because it’s black that it will be neutral. Don’t believe any colour patterns for that matter.

It’s very unlikely to be a neutral in South Africa.

Also you mention that there are three, so is this a 3-gang switch? Because it seems very strange there would be a three for a singular switch.

Is this one of those setups with a duplicate switch to the same light/application elsewhere? Then it’s definitely not neutral, but a secondary live.

Photos always help.
 

Steamy Tom

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Hey guys

Hoping you can help, I was looking at getting this smart switch. I just opened up my switch and saw something interesting, there are 3 live (red) 3 neutral (black) and a copper cable.

So it seems two live and two neutral come in. The two reds are on the in of the switch with the third one being on the exit. But all three the neutral wires are shorted together.

So if all three neutrals are shorted, do I put all three into the neutral of the switch or only one of the ones coming from one of the red wires (input not outgoing)?

Hope that makes sense.
Seems more likely that one is on the input and two on the outputs?

You sir are very lucky if those are indeed nuetrals. If they are though yes you could bundle it.
 

Kosmik

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Switches are normally wired in line with your live. Rare to see a proper neutral in a South African wall switch, power socket yes. If a switch has red on one side and black on the other, it's wires are totally wrong color in my opinion. There is no need for a switch on the neutral,
 

Geoff.D

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Hey guys

Hoping you can help, I was looking at getting this smart switch. I just opened up my switch and saw something interesting, there are 3 live (red) 3 neutral (black) and a copper cable.

So it seems two live and two neutral come in. The two reds are on the in of the switch with the third one being on the exit. But all three the neutral wires are shorted together.

So if all three neutrals are shorted, do I put all three into the neutral of the switch or only one of the ones coming from one of the red wires (input not outgoing)?

Hope that makes sense.
How many light switches are present? Is the one red conductor common to all the switches present, the centre pin normally.
If only one switch then one of the Red wires will be the incoming Live, the one common to that one will be outgoing to another switch somewhere and the third will be the live feed to a light fitting for the room in question, through the switch. The Incoming Neutral should be associated with the incoming live cable (twin earth). The Live feed to another switch will also have a neutral associated with the o/g live, and the third will feed the light fitting.
If All the neutrals are common then all three will have to be connected to the smart switch neutral to maintain neutral continuity --- you cannot break that link without causing problems.
Contrary to the statement above, the old standard required a neutral to be present in all light switch points --- it is only newer installations that did not have that as standard.

A photo will clear it all up.

And the statement that black is not neutral in SA is not true. The standard colour code still remains true, except in exceptional cases.
Red is live and black is neutral especially if all three are commoned together.

What has happened recently however is a failure by many installations to stick to the standard that Red and Black are used for incoming power feeds and daisy chain connections with light fittings fed with Red Live and Blue Neutral. (load)
 
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Dairyfarmer

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A conventional switch just breaks the Live circuit so doesn't need a Neutral. These switches need power to work (for the wifi and relay). So they need both a Live and Neutral. SA homes are not normally wired like that.

As far as having 3 of each, sounds like either a TWO gang or a 2 way switch (i.e. you have a duplicate switch elsewhere). Although I don't know why you would send both a neutral to a second switch because that switch would be using the common Neutral to power itself.

The bare wire is the Earth. Although the bulb itself doesn't need an Earth, the fitting and switch should be earthed. Or you can have all the electricity running through you body if anything shorted out. Your choice.
 

RetroRabbit

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Hi guys,

So I think my explanation needs some photos since it was quite ****. So here we go:

765618

765622

As you can see in the first photo there are three live wires, two into the switch one out. Second photo is 3 neutral wires shorted. I tested that they were indeed live and neutral with a multimeter. Was reading 220V across red and black.

Still unsure about which neutral to use. If you guys can maybe assist?
 

RetroRabbit

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Messages
90
A conventional switch just breaks the Live circuit so doesn't need a Neutral. These switches need power to work (for the wifi and relay). So they need both a Live and Neutral. SA homes are not normally wired like that.

As far as having 3 of each, sounds like either a TWO gang or a 2 way switch (i.e. you have a duplicate switch elsewhere). Although I don't know why you would send both a neutral to a second switch because that switch would be using the common Neutral to power itself.

The bare wire is the Earth. Although the bulb itself doesn't need an Earth, the fitting and switch should be earthed. Or you can have all the electricity running through you body if anything shorted out. Your choice.
There is only one switch for this light as you can see in my photos above. And then there is the bare copper wire which you can see as well.
 

RetroRabbit

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How many light switches are present? Is the one red conductor common to all the switches present, the centre pin normally.
If only one switch then one of the Red wires will be the incoming Live, the one common to that one will be outgoing to another switch somewhere and the third will be the live feed to a light fitting for the room in question, through the switch. The Incoming Neutral should be associated with the incoming live cable (twin earth). The Live feed to another switch will also have a neutral associated with the o/g live, and the third will feed the light fitting.
If All the neutrals are common then all three will have to be connected to the smart switch neutral to maintain neutral continuity --- you cannot break that link without causing problems.
Contrary to the statement above, the old standard required a neutral to be present in all light switch points --- it is only newer installations that did not have that as standard.

A photo will clear it all up.

And the statement that black is not neutral in SA is not true. The standard colour code still remains true, except in exceptional cases.
Red is live and black is neutral especially if all three are commoned together.

What has happened recently however is a failure by many installations to stick to the standard that Red and Black are used for incoming power feeds and daisy chain connections with light fittings fed with Red Live and Blue Neutral. (load)
Thanks for you explanation, I have posted two photos above where you can see the wiring inside the switch. Don't know if you can comment now that you've seen them?
 

Geoff.D

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So what you have is a daisy chain install. The two RED wires connected together are both Live, one incoming and one going to another light switch in another room. The single wire is to the light fitting. That switch should be marked "Live" and "Load".
The three neutrals are ALL to be connected to the smart switch replacement. The one to the light fitting is to complete the load circuit, and the other two must be connected as well to ensure continuity on the supply side.

In other words, just connect the combined twisted together neutrals to the neutral terminal on the smart switch.

There is one caveat. I am assuming there is only one light fitting in the room?
 

Tacet

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@RetroRabbit

The installation instructions for these is on the itead website. I don't see any version having multiple neutral connectors, though. The Sonoff itself should have only one neutral, and one live in, though depending on whether it is 1-gang, 2-gang or 3-gang, it will have multiple live out connectors.
 

MEIOT

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All neutral roads lead to rome :D

In other words, all neutral terminates on the neutral bus on the DB.

OP - I have exactly the same config as yours in most of my switches at home - I've replaced all my switches with Sonoffs and just ran a proper gauge cable from the bundled neutrals with a block to the neutral on the sonoff and live to live.

Works flawlessly. No need to separate the neutrals.

In fact - DONT separate the neutrals. Somewhere down the chain another neutral might be piggybacking off a neutral you might separate. Just causes more complications.
 

Steamy Tom

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@RetroRabbit

The installation instructions for these is on the itead website. I don't see any version having multiple neutral connectors, though. The Sonoff itself should have only one neutral, and one live in, though depending on whether it is 1-gang, 2-gang or 3-gang, it will have multiple live out connectors.
i am not even sure how to respond to this bra...
 

Steamy Tom

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All neutral roads lead to rome :D

In other words all netural terminates on the neutral bus on the DB.

OP - I have exactly the same config as yours in most of my switches at home - I've replaced all my switches with Sonoffs and just ran a proper gauge cable from the bundled neutrals with a block to the neutral on the sonoff and live to live.
unless the DB is split :p but then of course they wouldn't be bundled to begin with :p
 

MEIOT

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Oh ...and also....something to keep in mind - you might want to either get an electrician involved from the start or at least one to give it a once over when you're done and certifies your installation.

For insurance purposes.
 

The_Ogre

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This reminds me, I've got a bunch of Sonoff light-switches (from Banggood) which I ordered last year and didn't know about the need for a neutral.

I have no idea what my next step is going to be because pulling down a neutral will probably cost me quite a bit.
 

Tacet

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i am not even sure how to respond to this bra...
:X3: Yeah, sorry. I totally misread the OP - thought the OP had multiple neutral connectors on the Sonoff. I missed the part where the multiple neutrals and lives were in the current light switch fitting.

To me it sounds as though that light switch fitting was used as a junction box and not merely as a light switch fitting. Something like this. I hope this makes more sense.

765654
 

MEIOT

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This reminds me, I've got a bunch of Sonoff light-switches (from Banggood) which I ordered last year and didn't know about the need for a neutral.

I have no idea what my next step is going to be because pulling down a neutral will probably cost me quite a bit.
Any Sonoff POW's?

I'd be willing to take 'em off your hands for a bargain price :laugh:
 
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Tacet

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This reminds me, I've got a bunch of Sonoff light-switches (from Banggood) which I ordered last year and didn't know about the need for a neutral.

I have no idea what my next step is going to be because pulling down a neutral will probably cost me quite a bit.
It mostly depends on your light switch fittings' conduits. If they're accessible, then pulling in neutrals is easy. You can buy the cable yourself and supply it to the electrician. Problem is that in some houses (like mine), they've semented the top of the conduit closed. I'll need to grind/drill open the conduit to access it. So I'm rather looking at the Sonoff Mini, which will be a fair bit easier to install.
 

Geoff.D

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This reminds me, I've got a bunch of Sonoff light-switches (from Banggood) which I ordered last year and didn't know about the need for a neutral.

I have no idea what my next step is going to be because pulling down a neutral will probably cost me quite a bit.
It depends on how many conductors you have in each light box. And IF you are able to access the cabling in the ceiling and prepared to put in access boxes in the ceiling. And break a few rules maybe by doing yourself.


If the light switches are all single pole one gang light switches for each room meaning only two conductors (excluding the earth) both Red then you will have to pull in a neutral (conduit available) or chase a new cable into the wall.
If a few of them are single-pole multiple gang switches for multiple light fittings, THEN you van see if you can't "steal" a red conductor and use that for a neutral. Will have to mark the cable with black tape, and not show the CoC inspctor anything maybe. :ROFL:
 
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