Wifi light switch needs neutral wire. Why? AND Can that wire be a skinny one?Where do I run neutral from/to when replacing a SPST switch with one that requires neutral?How can I wire a new outlet from a light switch, with light switch set-up I've never seen before?Run additional wire from junction box to existing light switch?How to replace light switch that is daisy chained to other light switchesCan a white neutral wire be used as a three pole traveler wire?Trying to identify neutral wire in switch box to use with Wemo Light switch (more than one neutral wire seems to be present)Install TP Link Wifi Switch and problems along with itHow can I be sure a wire is truly neutral?Combine wireless and manual 3-way light switchNeutral wire is tied to my electric metal box, why is it so?
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Wifi light switch needs neutral wire. Why? AND Can that wire be a skinny one?
Where do I run neutral from/to when replacing a SPST switch with one that requires neutral?How can I wire a new outlet from a light switch, with light switch set-up I've never seen before?Run additional wire from junction box to existing light switch?How to replace light switch that is daisy chained to other light switchesCan a white neutral wire be used as a three pole traveler wire?Trying to identify neutral wire in switch box to use with Wemo Light switch (more than one neutral wire seems to be present)Install TP Link Wifi Switch and problems along with itHow can I be sure a wire is truly neutral?Combine wireless and manual 3-way light switchNeutral wire is tied to my electric metal box, why is it so?
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;
What does the neutral wire do on a light switch that responds to wifi?
My suspicion is that when the switch is in the off position, the electronics in the switch need to still be powered, so the neutral wire allows a tiny constant current through the switch so it can respond to a wifi instruction to actuate the switch.
If this is so, could the extra neutral wire going to the switch be a very light gauge wire?
switch light neutral wifi smart-switch
New contributor
add a comment |
What does the neutral wire do on a light switch that responds to wifi?
My suspicion is that when the switch is in the off position, the electronics in the switch need to still be powered, so the neutral wire allows a tiny constant current through the switch so it can respond to a wifi instruction to actuate the switch.
If this is so, could the extra neutral wire going to the switch be a very light gauge wire?
switch light neutral wifi smart-switch
New contributor
add a comment |
What does the neutral wire do on a light switch that responds to wifi?
My suspicion is that when the switch is in the off position, the electronics in the switch need to still be powered, so the neutral wire allows a tiny constant current through the switch so it can respond to a wifi instruction to actuate the switch.
If this is so, could the extra neutral wire going to the switch be a very light gauge wire?
switch light neutral wifi smart-switch
New contributor
What does the neutral wire do on a light switch that responds to wifi?
My suspicion is that when the switch is in the off position, the electronics in the switch need to still be powered, so the neutral wire allows a tiny constant current through the switch so it can respond to a wifi instruction to actuate the switch.
If this is so, could the extra neutral wire going to the switch be a very light gauge wire?
switch light neutral wifi smart-switch
switch light neutral wifi smart-switch
New contributor
New contributor
edited 4 hours ago
manassehkatz
12.2k1843
12.2k1843
New contributor
asked 5 hours ago
GyrobobGyrobob
61
61
New contributor
New contributor
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
Because unlike a normal switch, the wifi switch needs power, so it needs a neutral wire to complete a circuit at the switch between the unswitched hot wire and neutral for that power.
The neutral wire to the switch cannot be a light-gauge wire (at least if you are in an area subject to NEC codes; likely similar elsewhere in the world) because codes are based on what the circuit breaker protecting the circuit can supply when choosing wire size, so for 15A circuits the wire must be 14 Ga or larger, and for 20A circuits the wire must be 12Ga or larger. Smaller wires could overheat to the point of causing fires (without tripping the breaker) in the event of a fault condition, even if the normal current in them might be a matter of a few milliamperes.
I regard wifi switches (and thermostats) with the baleful gaze that only a network admin can view such things askance with, but I gather that there are units arranged in such a manner that the actual switch/relay can go in the ceiling where the light fixture that the switch loop originates from is, and the switch loop wires can (without adding any) be repurposed to operate the remote switch in the wall, no longer actually running the power for the lights through there. This type of unit will probably be much easier to install than to attempt to add a neutral wire to a switch box without one.
add a comment |
That is correct. In the mains power world, we have 3 wires.
EQUIPMENT SAFETY GROUND/EARTH which is not used for anything ever (except during a fault condition, of course)...
HOT which is what humans consider the "source" of power... and
NEUTRAL which is what humans consider the "power return". Obviously, it's AC, which makes "source" vs "return" rather arbitrary. This can be said: the system has equipotential bonding that, in normal conditions, places neutral quite close to safety earth. That's why it's called neutral.
When you want to power something 24x7, it must be connected between HOT and NEUTRAL. If it is not, it won't have power. Since presumably you want the WiFi switch to respond to WiFi at all times, you need HOT and NEUTRAL to pull that off.
You may be thinking of early dimmers. Those place themselves in series with the light bulb, so they connect between ALWAYS-HOT and SWITCHED-HOT. When the bulb is on, they create a small voltage drop and power themselves that way. When the bulb is off, they leak a small amount of current through the bulb, which works great with incandescents, but badly with most LEDs. It's possible to build a smart switch this way, in which case it does not need neutral. However it is difficult to design, and doesn't play well with most LEDs and CFLs. This can be solved by using 1 incandescent, or by putting a capacitor in parallel with the light bulbs so some power can leak through 24x7.
A very small number of dimmers place themselves in series with the equipotential bonding that keeps neutral near ground. In short, they bootleg neutral off of ground, but do so in very controlled conditions that satisfy Underwriter's Laboratories that it won't be unsafe. Don't do this yourself, unless instructed to by this particular device's UL-approved labeling and instructions.
If you don't want to hunt down a compatible smart switch, you need to replace the entire cable between light switch and light, with a /3 cable (black red white +ground). Then you make black always-hot, red switched-hot, and white neutral, hooking each as appropriate to the smart switch and up in the lamp.
If it is simpler to run power from the service panel, then run a /2 cable from the service panel to the switch, feed the lamp from the switch, and cap off the supply hot+neutral going into the lamp. (or disconnect it from the lamp circuit in all respects).
If conduit is used with individual wires (THHN), and hot and switched-hot are already colored wires, then you can simply add a similar (THHN) white wire to the pipe.
Other than that, you cannot just run an individual wire. I gather you're a DC electronics guy? This is AC, and magnetic fields from AC have a serious kick. So currents must be equal in all cables or conduits so magnetic fields cancel each other out. Which means all related wires must be in the same cable.
You are allowed to run an individual safety ground (i.e. retrofit), because current does not flow over safety ground (except during a fault).
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
1
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
1
@Gyrobob added.
– Harper
36 mins ago
add a comment |
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Because unlike a normal switch, the wifi switch needs power, so it needs a neutral wire to complete a circuit at the switch between the unswitched hot wire and neutral for that power.
The neutral wire to the switch cannot be a light-gauge wire (at least if you are in an area subject to NEC codes; likely similar elsewhere in the world) because codes are based on what the circuit breaker protecting the circuit can supply when choosing wire size, so for 15A circuits the wire must be 14 Ga or larger, and for 20A circuits the wire must be 12Ga or larger. Smaller wires could overheat to the point of causing fires (without tripping the breaker) in the event of a fault condition, even if the normal current in them might be a matter of a few milliamperes.
I regard wifi switches (and thermostats) with the baleful gaze that only a network admin can view such things askance with, but I gather that there are units arranged in such a manner that the actual switch/relay can go in the ceiling where the light fixture that the switch loop originates from is, and the switch loop wires can (without adding any) be repurposed to operate the remote switch in the wall, no longer actually running the power for the lights through there. This type of unit will probably be much easier to install than to attempt to add a neutral wire to a switch box without one.
add a comment |
Because unlike a normal switch, the wifi switch needs power, so it needs a neutral wire to complete a circuit at the switch between the unswitched hot wire and neutral for that power.
The neutral wire to the switch cannot be a light-gauge wire (at least if you are in an area subject to NEC codes; likely similar elsewhere in the world) because codes are based on what the circuit breaker protecting the circuit can supply when choosing wire size, so for 15A circuits the wire must be 14 Ga or larger, and for 20A circuits the wire must be 12Ga or larger. Smaller wires could overheat to the point of causing fires (without tripping the breaker) in the event of a fault condition, even if the normal current in them might be a matter of a few milliamperes.
I regard wifi switches (and thermostats) with the baleful gaze that only a network admin can view such things askance with, but I gather that there are units arranged in such a manner that the actual switch/relay can go in the ceiling where the light fixture that the switch loop originates from is, and the switch loop wires can (without adding any) be repurposed to operate the remote switch in the wall, no longer actually running the power for the lights through there. This type of unit will probably be much easier to install than to attempt to add a neutral wire to a switch box without one.
add a comment |
Because unlike a normal switch, the wifi switch needs power, so it needs a neutral wire to complete a circuit at the switch between the unswitched hot wire and neutral for that power.
The neutral wire to the switch cannot be a light-gauge wire (at least if you are in an area subject to NEC codes; likely similar elsewhere in the world) because codes are based on what the circuit breaker protecting the circuit can supply when choosing wire size, so for 15A circuits the wire must be 14 Ga or larger, and for 20A circuits the wire must be 12Ga or larger. Smaller wires could overheat to the point of causing fires (without tripping the breaker) in the event of a fault condition, even if the normal current in them might be a matter of a few milliamperes.
I regard wifi switches (and thermostats) with the baleful gaze that only a network admin can view such things askance with, but I gather that there are units arranged in such a manner that the actual switch/relay can go in the ceiling where the light fixture that the switch loop originates from is, and the switch loop wires can (without adding any) be repurposed to operate the remote switch in the wall, no longer actually running the power for the lights through there. This type of unit will probably be much easier to install than to attempt to add a neutral wire to a switch box without one.
Because unlike a normal switch, the wifi switch needs power, so it needs a neutral wire to complete a circuit at the switch between the unswitched hot wire and neutral for that power.
The neutral wire to the switch cannot be a light-gauge wire (at least if you are in an area subject to NEC codes; likely similar elsewhere in the world) because codes are based on what the circuit breaker protecting the circuit can supply when choosing wire size, so for 15A circuits the wire must be 14 Ga or larger, and for 20A circuits the wire must be 12Ga or larger. Smaller wires could overheat to the point of causing fires (without tripping the breaker) in the event of a fault condition, even if the normal current in them might be a matter of a few milliamperes.
I regard wifi switches (and thermostats) with the baleful gaze that only a network admin can view such things askance with, but I gather that there are units arranged in such a manner that the actual switch/relay can go in the ceiling where the light fixture that the switch loop originates from is, and the switch loop wires can (without adding any) be repurposed to operate the remote switch in the wall, no longer actually running the power for the lights through there. This type of unit will probably be much easier to install than to attempt to add a neutral wire to a switch box without one.
edited 5 hours ago
answered 5 hours ago
EcnerwalEcnerwal
58.3k24398
58.3k24398
add a comment |
add a comment |
That is correct. In the mains power world, we have 3 wires.
EQUIPMENT SAFETY GROUND/EARTH which is not used for anything ever (except during a fault condition, of course)...
HOT which is what humans consider the "source" of power... and
NEUTRAL which is what humans consider the "power return". Obviously, it's AC, which makes "source" vs "return" rather arbitrary. This can be said: the system has equipotential bonding that, in normal conditions, places neutral quite close to safety earth. That's why it's called neutral.
When you want to power something 24x7, it must be connected between HOT and NEUTRAL. If it is not, it won't have power. Since presumably you want the WiFi switch to respond to WiFi at all times, you need HOT and NEUTRAL to pull that off.
You may be thinking of early dimmers. Those place themselves in series with the light bulb, so they connect between ALWAYS-HOT and SWITCHED-HOT. When the bulb is on, they create a small voltage drop and power themselves that way. When the bulb is off, they leak a small amount of current through the bulb, which works great with incandescents, but badly with most LEDs. It's possible to build a smart switch this way, in which case it does not need neutral. However it is difficult to design, and doesn't play well with most LEDs and CFLs. This can be solved by using 1 incandescent, or by putting a capacitor in parallel with the light bulbs so some power can leak through 24x7.
A very small number of dimmers place themselves in series with the equipotential bonding that keeps neutral near ground. In short, they bootleg neutral off of ground, but do so in very controlled conditions that satisfy Underwriter's Laboratories that it won't be unsafe. Don't do this yourself, unless instructed to by this particular device's UL-approved labeling and instructions.
If you don't want to hunt down a compatible smart switch, you need to replace the entire cable between light switch and light, with a /3 cable (black red white +ground). Then you make black always-hot, red switched-hot, and white neutral, hooking each as appropriate to the smart switch and up in the lamp.
If it is simpler to run power from the service panel, then run a /2 cable from the service panel to the switch, feed the lamp from the switch, and cap off the supply hot+neutral going into the lamp. (or disconnect it from the lamp circuit in all respects).
If conduit is used with individual wires (THHN), and hot and switched-hot are already colored wires, then you can simply add a similar (THHN) white wire to the pipe.
Other than that, you cannot just run an individual wire. I gather you're a DC electronics guy? This is AC, and magnetic fields from AC have a serious kick. So currents must be equal in all cables or conduits so magnetic fields cancel each other out. Which means all related wires must be in the same cable.
You are allowed to run an individual safety ground (i.e. retrofit), because current does not flow over safety ground (except during a fault).
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
1
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
1
@Gyrobob added.
– Harper
36 mins ago
add a comment |
That is correct. In the mains power world, we have 3 wires.
EQUIPMENT SAFETY GROUND/EARTH which is not used for anything ever (except during a fault condition, of course)...
HOT which is what humans consider the "source" of power... and
NEUTRAL which is what humans consider the "power return". Obviously, it's AC, which makes "source" vs "return" rather arbitrary. This can be said: the system has equipotential bonding that, in normal conditions, places neutral quite close to safety earth. That's why it's called neutral.
When you want to power something 24x7, it must be connected between HOT and NEUTRAL. If it is not, it won't have power. Since presumably you want the WiFi switch to respond to WiFi at all times, you need HOT and NEUTRAL to pull that off.
You may be thinking of early dimmers. Those place themselves in series with the light bulb, so they connect between ALWAYS-HOT and SWITCHED-HOT. When the bulb is on, they create a small voltage drop and power themselves that way. When the bulb is off, they leak a small amount of current through the bulb, which works great with incandescents, but badly with most LEDs. It's possible to build a smart switch this way, in which case it does not need neutral. However it is difficult to design, and doesn't play well with most LEDs and CFLs. This can be solved by using 1 incandescent, or by putting a capacitor in parallel with the light bulbs so some power can leak through 24x7.
A very small number of dimmers place themselves in series with the equipotential bonding that keeps neutral near ground. In short, they bootleg neutral off of ground, but do so in very controlled conditions that satisfy Underwriter's Laboratories that it won't be unsafe. Don't do this yourself, unless instructed to by this particular device's UL-approved labeling and instructions.
If you don't want to hunt down a compatible smart switch, you need to replace the entire cable between light switch and light, with a /3 cable (black red white +ground). Then you make black always-hot, red switched-hot, and white neutral, hooking each as appropriate to the smart switch and up in the lamp.
If it is simpler to run power from the service panel, then run a /2 cable from the service panel to the switch, feed the lamp from the switch, and cap off the supply hot+neutral going into the lamp. (or disconnect it from the lamp circuit in all respects).
If conduit is used with individual wires (THHN), and hot and switched-hot are already colored wires, then you can simply add a similar (THHN) white wire to the pipe.
Other than that, you cannot just run an individual wire. I gather you're a DC electronics guy? This is AC, and magnetic fields from AC have a serious kick. So currents must be equal in all cables or conduits so magnetic fields cancel each other out. Which means all related wires must be in the same cable.
You are allowed to run an individual safety ground (i.e. retrofit), because current does not flow over safety ground (except during a fault).
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
1
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
1
@Gyrobob added.
– Harper
36 mins ago
add a comment |
That is correct. In the mains power world, we have 3 wires.
EQUIPMENT SAFETY GROUND/EARTH which is not used for anything ever (except during a fault condition, of course)...
HOT which is what humans consider the "source" of power... and
NEUTRAL which is what humans consider the "power return". Obviously, it's AC, which makes "source" vs "return" rather arbitrary. This can be said: the system has equipotential bonding that, in normal conditions, places neutral quite close to safety earth. That's why it's called neutral.
When you want to power something 24x7, it must be connected between HOT and NEUTRAL. If it is not, it won't have power. Since presumably you want the WiFi switch to respond to WiFi at all times, you need HOT and NEUTRAL to pull that off.
You may be thinking of early dimmers. Those place themselves in series with the light bulb, so they connect between ALWAYS-HOT and SWITCHED-HOT. When the bulb is on, they create a small voltage drop and power themselves that way. When the bulb is off, they leak a small amount of current through the bulb, which works great with incandescents, but badly with most LEDs. It's possible to build a smart switch this way, in which case it does not need neutral. However it is difficult to design, and doesn't play well with most LEDs and CFLs. This can be solved by using 1 incandescent, or by putting a capacitor in parallel with the light bulbs so some power can leak through 24x7.
A very small number of dimmers place themselves in series with the equipotential bonding that keeps neutral near ground. In short, they bootleg neutral off of ground, but do so in very controlled conditions that satisfy Underwriter's Laboratories that it won't be unsafe. Don't do this yourself, unless instructed to by this particular device's UL-approved labeling and instructions.
If you don't want to hunt down a compatible smart switch, you need to replace the entire cable between light switch and light, with a /3 cable (black red white +ground). Then you make black always-hot, red switched-hot, and white neutral, hooking each as appropriate to the smart switch and up in the lamp.
If it is simpler to run power from the service panel, then run a /2 cable from the service panel to the switch, feed the lamp from the switch, and cap off the supply hot+neutral going into the lamp. (or disconnect it from the lamp circuit in all respects).
If conduit is used with individual wires (THHN), and hot and switched-hot are already colored wires, then you can simply add a similar (THHN) white wire to the pipe.
Other than that, you cannot just run an individual wire. I gather you're a DC electronics guy? This is AC, and magnetic fields from AC have a serious kick. So currents must be equal in all cables or conduits so magnetic fields cancel each other out. Which means all related wires must be in the same cable.
You are allowed to run an individual safety ground (i.e. retrofit), because current does not flow over safety ground (except during a fault).
That is correct. In the mains power world, we have 3 wires.
EQUIPMENT SAFETY GROUND/EARTH which is not used for anything ever (except during a fault condition, of course)...
HOT which is what humans consider the "source" of power... and
NEUTRAL which is what humans consider the "power return". Obviously, it's AC, which makes "source" vs "return" rather arbitrary. This can be said: the system has equipotential bonding that, in normal conditions, places neutral quite close to safety earth. That's why it's called neutral.
When you want to power something 24x7, it must be connected between HOT and NEUTRAL. If it is not, it won't have power. Since presumably you want the WiFi switch to respond to WiFi at all times, you need HOT and NEUTRAL to pull that off.
You may be thinking of early dimmers. Those place themselves in series with the light bulb, so they connect between ALWAYS-HOT and SWITCHED-HOT. When the bulb is on, they create a small voltage drop and power themselves that way. When the bulb is off, they leak a small amount of current through the bulb, which works great with incandescents, but badly with most LEDs. It's possible to build a smart switch this way, in which case it does not need neutral. However it is difficult to design, and doesn't play well with most LEDs and CFLs. This can be solved by using 1 incandescent, or by putting a capacitor in parallel with the light bulbs so some power can leak through 24x7.
A very small number of dimmers place themselves in series with the equipotential bonding that keeps neutral near ground. In short, they bootleg neutral off of ground, but do so in very controlled conditions that satisfy Underwriter's Laboratories that it won't be unsafe. Don't do this yourself, unless instructed to by this particular device's UL-approved labeling and instructions.
If you don't want to hunt down a compatible smart switch, you need to replace the entire cable between light switch and light, with a /3 cable (black red white +ground). Then you make black always-hot, red switched-hot, and white neutral, hooking each as appropriate to the smart switch and up in the lamp.
If it is simpler to run power from the service panel, then run a /2 cable from the service panel to the switch, feed the lamp from the switch, and cap off the supply hot+neutral going into the lamp. (or disconnect it from the lamp circuit in all respects).
If conduit is used with individual wires (THHN), and hot and switched-hot are already colored wires, then you can simply add a similar (THHN) white wire to the pipe.
Other than that, you cannot just run an individual wire. I gather you're a DC electronics guy? This is AC, and magnetic fields from AC have a serious kick. So currents must be equal in all cables or conduits so magnetic fields cancel each other out. Which means all related wires must be in the same cable.
You are allowed to run an individual safety ground (i.e. retrofit), because current does not flow over safety ground (except during a fault).
edited 36 mins ago
answered 1 hour ago
HarperHarper
79.7k552159
79.7k552159
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
1
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
1
@Gyrobob added.
– Harper
36 mins ago
add a comment |
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
1
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
1
@Gyrobob added.
– Harper
36 mins ago
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
So I would guess the solution, then, is to run a 14 gauge wire from the wifi light switch all the way back to the circuit breaker box (about 50') and attach it to the neutral buss.
– Gyrobob
57 mins ago
1
1
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
@Gyrobob Harper will, I am sure, explain in full detail. But basically: 1 - You would likely find it shorter to run from the switch to the light fixture, as neutral is always present on the fixture (one side switched hot, one side neutral). 2 - You can't run a wire by itself - if you have individual wires in conduit, you can it together with the existing hot/switched hot wires; if you have cable then you need to replace the cable with a cable that has an extra wire for neutral.
– manassehkatz
51 mins ago
1
1
@Gyrobob added.
– Harper
36 mins ago
@Gyrobob added.
– Harper
36 mins ago
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Gyrobob is a new contributor. Be nice, and check out our Code of Conduct.
Gyrobob is a new contributor. Be nice, and check out our Code of Conduct.
Gyrobob is a new contributor. Be nice, and check out our Code of Conduct.
Gyrobob is a new contributor. Be nice, and check out our Code of Conduct.
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