why some residential dimmer is using ground wire as neutral?

[kylelee]

There are some dimmer like luthron Bluetooth/wifi dimmer that doesn't require neutral (maybe it is designed for some switch not having neutral ). But by code. We are not allowed to use equipment group as returning. Why such big company are allow to do this?


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[electrofelon]

There are some dimmer like luthron Bluetooth/wifi dimmer that doesn't require neutral (maybe it is designed for some switch not having neutral ). But by code. We are not allowed to use equipment group as returning. Why such big company are allow to do this?


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There has been a longstanding battle between UL and the NEC over this. UL allows devices to put a few milliamps on the EGC system (don't remember exact figure ).

 

[shortcircuit2]

Using the equipment grounding conductor for electronic controls will be phased out with the new language in 404.2(C) of the 2017 NEC. The exception to 404.2(C) gives 1-1-2020 as the effective date for new work.

There is a exception for existing installations where a device replacement is needed but there will be a limit of 5 controls on a branch circuit and no more than 25 on a feeder.

 

[electrofelon]

Using the equipment grounding conductor for electronic controls will be phased out with the new language in 404.2(C) of the 2017 NEC. The exception to 404.2(C) gives 1-1-2020 as the effective date for new work.

There is a exception for existing installations where a device replacement is needed but there will be a limit of 5 controls on a branch circuit and no more than 25 on a feeder.

But will manufacturers start supplying controls with a white wire? It seems to me that this would have to be coordinated with UL standards to be enforceable.

 

[kylelee]

Using the equipment grounding conductor for electronic controls will be phased out with the new language in 404.2(C) of the 2017 NEC. The exception to 404.2(C) gives 1-1-2020 as the effective date for new work.

There is a exception for existing installations where a device replacement is needed but there will be a limit of 5 controls on a branch circuit and no more than 25 on a feeder.

so if this branch circuit is ported by GFCI/AFCI ,it will trip the GFCI?and looks before the manufacturer would I to use equipment grounding than neutral


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[jumper]

But will manufacturers start supplying controls with a white wire? It seems to me that this would have to be coordinated with UL standards to be enforceable.

Except for a few exceptions I believe that the 2017 mandates that new devices must be in play by 2020.

 

[jumper]

There has been a longstanding battle between UL and the NEC over this. UL allows devices to put a few milliamps on the EGC system (don't remember exact figure ).

500uA microamps. or .5mA milliamps.

 

[GoldDigger]

so if this branch circuit is ported by GFCI/AFCI ,it will trip the GFCI?and looks before the manufacturer would I to use equipment grounding than neutral


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As stated, each device is allowed a maximum current of .5ma to the EGC, so if all else is perfect it would take 8 to 12 such devices on one circuit to cause a GFCI trip.

 

[electrofelon]

Except for a few exceptions I believe that the 2017 mandates that new devices must be in play by 2020.

I still think UL has to cooperate though. If they still list devices with a green wire (that puts current on it), how do we know if it is putting current on that green wire?

 

[jumper]

I still think UL has to cooperate though. If they still list devices with a green wire (that puts current on it), how do we know if it is putting current on that green wire?

Not totally clear on question. Is it....

How will we know if manufacturers will comply?

or

How will we know that UL will test and verify compliance?

 

[electrofelon]

Not totally clear on question. Is it....

How will we know if manufacturers will comply?

or

How will we know that UL will test and verify compliance?

Yes and yes and...
I think the language prohibiting load side grounded conductor connections to the egc was already in the code. I don't see how the new language changes anything

 

[GoldDigger]

Yes and yes and...
I think the language prohibiting load side grounded conductor connections to the egc was already in the code. I don't see how the new language changes anything

The new language does not change anything in the NEC in terms of prohibiting EGC return devices. What it does is set up conditions that persuade UL that they can now go ahead and refuse to list such devices.

 

[electrofelon]

What it does is set up conditions that persuade UL that they can now go ahead and refuse to list such devices.

I agree with that

 

[kwired]

The new language does not change anything in the NEC in terms of prohibiting EGC return devices. What it does is set up conditions that persuade UL that they can now go ahead and refuse to list such devices.

I think they can list them however they want. NEC can still prohibit use of the EGC as a current carrying conductor.

To be useful to us, NEC and UL need to be on same page though.

 

[electrofelon]

Do most dimmers still use the egc to power the device, or are they able to power it in series with the load (even thru led and cfl????)? Maestro come to mind. I always found it strange, the maestro dimmers don't have a neutral, but the maestro switches do.