- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Is this think compliant? I think not
that switch setup is using the three way system to switch the neutral power not the hot... but the dimmer itself is the only part of the circuit carrying the hot as well. Not too sure about that. Normally, isn't it the hot that gets switched and neutral is run short?
404.2 Switch Connections. (A) Three-Way and Four-Way Switches. Three-way and fourway switches shall be wired so that all switching is done only in the ungrounded circuit conductor. Where in metal raceways or metal-armored cables, wiring between switches and outlets shall be in accordance with 300.20(A). Exception: Switch loops shall not require a grounded conductor. (B) Grounded Conductors. Switches or circuit breakers shall not disconnect the grounded conductor of a circuit. Exception: A switch or circuit breaker shall be permitted to disconnect a grounded circuit conductor where all circuit conductors are disconnected simultaneously, or where the device is arranged so that the grounded conductor cannot be disconnected until all the ungrounded conductors of the circuit have been disconnected.
thus it violates code, at least how I read it, unless I have not read the section correctly.
I don't think you are actually switching the neutral. You are driving the voltage on the red wire to zero as part of the internal electronic logic in the dimmer switch. I assume the internal logic drives some type of electronic latching relay, and every time the voltage status of the red wire terminal changes the latching relay changes state. That permits the 3 way dimmer to be used with a standard switch at the other location.
I don't think you are actually switching the neutral. You are driving the voltage on the red wire to zero as part of the internal electronic logic in the dimmer switch. I assume the internal logic drives some type of electronic latching relay, and every time the voltage status of the red wire terminal changes the latching relay changes state. That permits the 3 way dimmer to be used with a standard switch at the other location.
What I see here is line and load on the zen dimmer with a constant neutral and then a neutral switched from the other 3 way-- that 3 way only has 2 terminals connected. Technically we are switching the neutral but there is always a neutral unswitched at the light.
I am not sure how the standard 3 way is actually controlling the load on the Zen dimmer.