Which neutral to use

Kosmik

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Set default on state so that it still behaves with the wall switch.
 

MEIOT

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ok but they i am guessing your light switches origional wiring isnt the one providing power to the sonoff for live.
yes - it is - the original wiring is going in to the input live and neutral on the sonoff.

The physical switch just connects on the GPIO pins. No power goes through the physical switch itself. It just tells the sonoff to turn on or off when the switch is triggered manually.

Life with Sonoffs become much easier with Tasmota CFW as well - in the Tasmota interface you can specify exactly how you want the physical switch to behave and other cool settings like retain last state on power off etc
 

MEIOT

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The issue is the 3 neutrals are crimped together in a large ferrel, not just put into a chocolate block. Would I need to remove that crimp and add the cable then recrimp?
Easiest thing to do is unbundle those 3 Neutrals - insert all 3 copper ends in to one end of a block - screw them in - get another matching gauge length of black cable - screw that copper end in to the other end of the block - it's just a join using the block in essence

Actually - the load side also needs a Neutral - so 2 lengths coming out the other end of the block. One for Input and one for Output (Load)

Please make sure your mains are turned off first :laugh:
 

Steamy Tom

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yes - it is - the original wiring is going in to the input live and neutral on the sonoff.

The physical switch just connects on the GPIO pins. No power goes through the physical switch itself. It just tells the sonoff to turn on or off when the switch is triggered manually.

Life with Sonoffs become much easier with Tasmota CFW as well - in the Tasmota interface you can specify exactly how you want the physical switch to behave and other cool settings like retain last state on power off etc
ok but then you had power direct to your light fitting also
 

MEIOT

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ok but then you had power direct to your light fitting also
No - power is switched by the Sonoff. On the Sonoff Input side is where the power goes in.

On the Sonoff Output side is where the load (light fitting goes in).

So there's no direct power pe se to the actual light fitting. If for some reason the Sonoff blows a fuse and loses power to it's circuity it becomes impossible to turn the switch on either manually using the flip/toggle switch or through the app even though power to the Input side is still fine.

All the manual wall switch that's plugged in to the GPIO pins does is send a command to the Sonoff to turn on or off.
 

RetroRabbit

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Easiest thing to do is unbundle those 3 Neutrals - insert all 3 copper ends in to one end of a block - screw them in - get another matching gauge length of black cable - screw that copper end in to the other end of the block - it's just a join using the block in essence

Actually - the load side also needs a Neutral - so 2 lengths coming out the other end of the block. One for Input and one for Output (Load)

Please make sure your mains are turned off first :laugh:
How the hell do I get them unbundled from the ferrel they've been crimped in? I would like to avoid cutting it off but if it's the only way I'll do so.
 

Geoff.D

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The issue is the 3 neutrals are crimped together in a large ferrel, not just put into a chocolate block. Would I need to remove that crimp and add the cable then recrimp?
If the cables are long enough to crimp, remove and use a new ferrule, otherwise replace with that much-hated thing called a chocolate block.
 

MEIOT

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How the hell do I get them unbundled from the ferrel they've been crimped in? I would like to avoid cutting it off but if it's the only way I'll do so.
Going on that pic you posted, there seems ample slack on those neutrals to cut and strip the ends. Else, as @Geoff.D mentioned above
 

Steamy Tom

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No - power is switched by the Sonoff. On the Sonoff Input side is where the power goes in.

On the Sonoff Output side is where the load (light fitting goes in).

So there's no direct power pe se to the actual light fitting. If for some reason the Sonoff blows a fuse and loses power to it's circuity it becomes impossible to turn the switch on either manually using the flip/toggle switch or through the app even though power to the Input side is still fine.

All the manual wall switch that's plugged in to the GPIO pins does is send a command to the Sonoff to turn on or off.
we are missing each other here. currently a normal light has a neutral to it and a switched live right? so now i ask, how did you get power to your light fitting without considering the switch, did you have power there already?
 

MEIOT

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we are missing each other here. currently a normal light has a neutral to it and a switched live right? so now i ask, how did you get power to your light fitting without considering the switch, did you have power there already?
Oh - Yes.

Have a look at the 2 pics @ RetroRabbit posted. You'll notice on the actual wall switch there are 2 red connections to the switch. One is to the load (light switch) the other is the actual Live from the DB. The neutrals in the cavity are just bundled together not connected to the switch.

My initial configuration matched the OP's exactly where the neutrals weren't wired in to the switch but also bundled in the cavities.
 

Steamy Tom

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Oh - Yes.

Have a look at the 2 pics @ RetroRabbit posted. You'll notice on the actual wall switch there are 2 red connections to the switch. One is to the load (light switch) the other is the actual Live from the DB. The neutrals in the cavity are just bundled together not connected to the switch.

My initial configuration matched the OP's exactly where the neutrals weren't wired in to the switch but also bundled in the cavities.
ok i think we are on the same page, you didn't wire it in the fitting, you wired it in the wall switch.
 

Tacet

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That is it but really you could have come up with a better drawing.:cool:
:laugh: Very true. Time was against me, though.

Arb question, as the fitting would already have a neutral at its end and live wire from it to the switch, why not just piggy back off that neutral point to the wall switch? Should be a easy enough push one wire down conduit?
I wouldn't do that. That neutral already needs to carry all the current from the plug's live. Now you add some current from a light's live as well. This could possibly overload the neutral, which was only sized to carry the plug's current. And I doubt that your circuit breakers will trip, as they're both on the plug and light's lives respectively. Its one of those cases where it should be fine, and your house shouldn't burn down, but you do have a neutral that you don't know if it is really adequately sized for the load it possibly carry.
 

Kosmik

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:laugh: Very true. Time was against me, though.



I wouldn't do that. That neutral already needs to carry all the current from the plug's live. Now you add some current from a light's live as well. This could possibly overload the neutral, which was only sized to carry the plug's current. And I doubt that your circuit breakers will trip, as they're both on the plug and light's lives respectively. Its one of those cases where it should be fine, and your house shouldn't burn down, but you do have a neutral that you don't know if it is really adequately sized for the load it possibly carry.
That neutral will only assist the sonnoffs internal workings, seriously doubt it would be any meaningful additional load.

Oh and I wasnt talking about a plug socket, I was saying bring a wire back from the light fitting the switch is powering.
 
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Tacet

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That neutral will only assist the sonnoffs internal workings, seriously doubt it would be any meaningful additional load.
It shouldn't cause issues, and I'll admit to having done the same. But you now have a neutral that is part of two circuits. 10142 wants your neutral to be the same current carrying capacity as the phase conductor, which won't be the case if you effectively have two phase conductors connected to it. It will work, but its not practice I'd advocate at all.
 

Kosmik

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It shouldn't cause issues, and I'll admit to having done the same. But you now have a neutral that is part of two circuits. 10142 wants your neutral to be the same current carrying capacity as the phase conductor, which won't be the case if you effectively have two phase conductors connected to it. It will work, but its not practice I'd advocate at all.
Neutral is common though and its still a single circuit to one breaker ie: live -> switch\sonoff -> light. All its doing is extending the neutral to the sonoff making it a common rail for both sonoff and light..
 

The_Ogre

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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 switchIMG_20200321_100324.jpg
 
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