marmathsen
Senior Member
- Location
- Seattle, Washington ...ish
- Occupation
- Electrical Contractor
Can someone help me interpret the Exception to 404.2(C)?
(C) Switches Controlling Lighting Loads.
The grounded circuit conductor for the controlled lighting circuit shall be installed at the location where switches control lighting loads that are supplied by a grounded general-purpose branch circuit serving bathrooms, hallways, stairways, and habitable rooms or occupiable spaces as defined in the applicable building code. Where multiple switch locations control the same lighting load such that the entire floor area of the room or space is visible from the single or combined switch locations, the grounded circuit conductor shall only be required at one location. A grounded conductor shall not be required to be installed at lighting switch locations under any of the following conditions:
(1) Where conductors enter the box enclosing the switch through a raceway, provided that the raceway is large enough for all contained conductors, including a grounded conductor
(2) Where the box enclosing the switch is accessible for the installation of an additional or replacement cable without removing finish materials
(3) Where snap switches with integral enclosures comply with 300.15(E)
(4) Where lighting in the area is controlled by automatic means
(5) Where a switch controls a receptacle load
The grounded conductor shall be extended to any switch location as necessary and shall be connected to switching devices that require line-to-neutral voltage to operate the electronics of the switch in the standby mode and shall meet the requirements of 404.22.
Exception:
The connection requirement shall become effective on January 1, 2020. It shall not apply to replacement or retrofit switches installed in locations prior to local adoption of 404.2(C) and where the grounded conductor cannot be extended without removing finish materials. The number of electronic control switches on a branch circuit shall not exceed five, and the number connected to any feeder on the load side of a system or main bonding jumper shall not exceed 25. For the purpose of this exception, a neutral busbar, in compliance with 200.2(B) and to which a main or system bonding jumper is connected shall not be limited as to the number of electronic lighting control switches connected.
When they refer to the device limit, am I to assume they are referring to devices that aren't connected to the grounded neutral conductor and are presumably using the EGC as a return path for "standby current"?
Is the limit only applicable in retrofit scenarios?
I can't imagine this exception is trying to say I can connect a white wire to the EGC...is it?
If a device (i.e. a Lutron Caséta PD-6WCL) doesn't have a white neutral wire, am I to assume that it's using the EGC in the standby state and therefore I need to limit my device quantities by the exception above?
When is the device limit supposed to come into play? It seems pretty clear that there is no device limit if the EGC is connected to the neutral bar in a service panel (basically non existent with 230.85), or if using the neutral conductor.
It sorta seems like they dumped a bunch of separate items into the exception. It seems like the effective date should have been an informational note, the sentence about retrofit applications should have been a 7th item above, and the part about device limits should have just been in the body of the code article.
Thanks for your input.
(C) Switches Controlling Lighting Loads.
The grounded circuit conductor for the controlled lighting circuit shall be installed at the location where switches control lighting loads that are supplied by a grounded general-purpose branch circuit serving bathrooms, hallways, stairways, and habitable rooms or occupiable spaces as defined in the applicable building code. Where multiple switch locations control the same lighting load such that the entire floor area of the room or space is visible from the single or combined switch locations, the grounded circuit conductor shall only be required at one location. A grounded conductor shall not be required to be installed at lighting switch locations under any of the following conditions:
(1) Where conductors enter the box enclosing the switch through a raceway, provided that the raceway is large enough for all contained conductors, including a grounded conductor
(2) Where the box enclosing the switch is accessible for the installation of an additional or replacement cable without removing finish materials
(3) Where snap switches with integral enclosures comply with 300.15(E)
(4) Where lighting in the area is controlled by automatic means
(5) Where a switch controls a receptacle load
The grounded conductor shall be extended to any switch location as necessary and shall be connected to switching devices that require line-to-neutral voltage to operate the electronics of the switch in the standby mode and shall meet the requirements of 404.22.
Exception:
The connection requirement shall become effective on January 1, 2020. It shall not apply to replacement or retrofit switches installed in locations prior to local adoption of 404.2(C) and where the grounded conductor cannot be extended without removing finish materials. The number of electronic control switches on a branch circuit shall not exceed five, and the number connected to any feeder on the load side of a system or main bonding jumper shall not exceed 25. For the purpose of this exception, a neutral busbar, in compliance with 200.2(B) and to which a main or system bonding jumper is connected shall not be limited as to the number of electronic lighting control switches connected.
When they refer to the device limit, am I to assume they are referring to devices that aren't connected to the grounded neutral conductor and are presumably using the EGC as a return path for "standby current"?
Is the limit only applicable in retrofit scenarios?
I can't imagine this exception is trying to say I can connect a white wire to the EGC...is it?
If a device (i.e. a Lutron Caséta PD-6WCL) doesn't have a white neutral wire, am I to assume that it's using the EGC in the standby state and therefore I need to limit my device quantities by the exception above?
When is the device limit supposed to come into play? It seems pretty clear that there is no device limit if the EGC is connected to the neutral bar in a service panel (basically non existent with 230.85), or if using the neutral conductor.
It sorta seems like they dumped a bunch of separate items into the exception. It seems like the effective date should have been an informational note, the sentence about retrofit applications should have been a 7th item above, and the part about device limits should have just been in the body of the code article.
Thanks for your input.
