Which neutral to use

smc

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Can anybody explain this to me? Is this black a neutral?

Apologies about the quality. Wife took the pic while I was busy with the Sonoff switch
Yes, black is neutral. Twisted red wires are live (one is live feed in, one goes to next switch as its live feed). Single red goes to load. Assuming of course that whoever wired this is sane/followed normal practice.
 

Geoff.D

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Yes the black is the neutral, commoner as per regulations, one is the supply side from the DB, the othe
Can anybody explain this to me? Is this black a neutral?

Apologies about the quality. Wife took the pic while I was busy with the Sonoff switchView attachment 804331
The twisted together Red and twisted together black cables are both " supply feeds" coming from the CB in the DB and the neutral bar in the DB.
The single Red is the load power feed to the light fitting.
The neutral from the light fitting is wired directly to the DB neutral.

This is a classic example of two "standards" being implemented in one installation - in my book a very bad wiring practice.
If you use the daisy chain standard, then the light fitting should be fed with a neutral and a Load live wire from the switch box to the light fitting.
It means that any Sonoff type installation add-ons are now complicated because there are two neutral paths for the return current. If the Sonoff switch is installed in the switch box, a separate neutral wire should be drawn in to ensure proper operation of the sonoff device.
 

The_Ogre

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Yes the black is the neutral, commoner as per regulations, one is the supply side from the DB, the othe

The twisted together Red and twisted together black cables are both " supply feeds" coming from the CB in the DB and the neutral bar in the DB.
The single Red is the load power feed to the light fitting.
The neutral from the light fitting is wired directly to the DB neutral.

This is a classic example of two "standards" being implemented in one installation - in my book a very bad wiring practice.
If you use the daisy chain standard, then the light fitting should be fed with a neutral and a Load live wire from the switch box to the light fitting.
It means that any Sonoff type installation add-ons are now complicated because there are two neutral paths for the return current. If the Sonoff switch is installed in the switch box, a separate neutral wire should be drawn in to ensure proper operation of the sonoff device.
Thank God I fell asleep while waiting for you guys to respond.

You reckon I should abort? I have the light switches and everything
 

Geoff.D

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No just evaluate how and where you want to install the Sonoff devices.
 

The_Ogre

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No just evaluate how and where you want to install the Sonoff devices.
OK, just please reassure me of which cables go in where. For the light I posted above, I plan on using the black coloured switch. JPEG_20200321_161814_9173375515603869927.jpgJPEG_20200321_161835_9003313223776596055.jpg
 

Geoff.D

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Both those are simple, as they have only 1 Neutral connection.

The twisted black pair (both) gets connected to the terminal marked "N".
The twisted Red pair ( both) gets connected to "L in" which is the supply side.
The single or double etc Red wire/s is/are connected to the terminals marked "L out".
 

The_Ogre

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Both those are simple, as they have only 1 Neutral connection.

The twisted black pair (both) gets connected to the terminal marked "N".
The twisted Red pair ( both) gets connected to "L in" which is the supply side.
The single or double etc Red wire/s is/are connected to the terminals marked "L out".
I went ahead and did it while waiting. Just like you said.

Working 100%. Now to get my daughter to stop playing with it with her phone. Jisis :(
 

The_Ogre

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@smc @MEIOT @Geoff.D I need your help again, I don't want to burn down my house!

Current circuit connected to en suit and main bedroom light:

1585073867326.png

And then the connectors to which the cables need to be connected:

1585074025797.png


Front of the switch:

1585074107822.png
 

smc

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Its a bit difficult to see what's going on with the screw terminal connector in the photo, but probably:

1. All the blacks (not what looks like a bare copper wire, that's probably the earth) to N in
2. Red wire on the right of the photo (bridged to the second switch) to L in
3. The other two red wires to L1 Out and L2 Out respectively

But check whether what looks like a bare wire in photo actually is a bare wire or is another black.
 

Geoff.D

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Now that switch is correctly wired in all respects with the neutral from each fitting commoned on the chocolate block.
Run a wire from the chocolate block to the terminal marked "N".
The Red wire connected to both existing switches goes to " L in".
The other two red wires go to "L1 out" and "L2 out" respectively.

edit:/ Snap @smc
 
Last edited:

Geoff.D

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And then another example of the crap workmanship done by the professionals. Instead of getting the right screws to mount the switch, they go and use black screws and mess up the threads in the switchbox forever!
 

The_Ogre

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Its a bit difficult to see what's going on with the screw terminal connector in the photo, but probably:

1. All the blacks (not what looks like a bare copper wire, that's probably the earth) to N in
2. Red wire on the right of the photo (bridged to the second switch) to L in
3. The other two red wires to L1 Out and L2 Out respectively

But check whether what looks like a bare wire in photo actually is a bare wire or is another black.
Now that switch is correctly wired in all respects with the neutral from each fitting commoned on the chocolate block.
Run a wire from the chocolate block to the terminal marked "N".
The Red wire connected to both existing switches goes to " L in".
The other two red wires go to "L1 out" and "L2 out" respectively.
Let me try it quickly - I should have saved this for my corona period :(
 

The_Ogre

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Now that switch is correctly wired in all respects with the neutral from each fitting commoned on the chocolate block.
Run a wire from the chocolate block to the terminal marked "N".
The Red wire connected to both existing switches goes to " L in".
The other two red wires go to "L1 out" and "L2 out" respectively.

edit:/ Snap @smc
Working 100%. Thanks gents

This paves the way for connecting the rest of the switches
 
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The_Ogre

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Jisis. I don't even know how to start here.

@Geoff.D @smc lounge downlighters and outside lights switch. I want to connect it to exactly the same model of Sonoff double switch as the previous oneJPEG_20200325_123802_8998399304024049464.jpgJPEG_20200325_123835_6846891420609960944.jpgJPEG_20200325_123933_1168834309392986960.jpg
 

smc

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Jisis. I don't even know how to start here.

@Geoff.D @smc lounge downlighters and outside lights switch. I want to connect it to exactly the same model of Sonoff double switch as the previous one
Hmmm. I don't like the look of that very much. Particularly what looks like a lone neutral wire going to the switch on the left. Is that just a switch? (a) Can you show a picture of the faceplate? (b) can you tell which of the red wires that lone neutral is paired to?
 

The_Ogre

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Hmmm. I don't like the look of that very much. Particularly what looks like a lone neutral wire going to the switch on the left. Is that just a switch? (a) Can you show a picture of the faceplate? (b) can you tell which of the red wires that lone neutral is paired to?
Hope the quality is not too crapJPEG_20200325_130657_6093194932184335247.jpgJPEG_20200325_130731_4709860791009253876.jpgJPEG_20200325_130752_1817097011086488386.jpg
 
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