Change Summary

• New provisions were added for “Electronic Lighting Controlled Switches” prohibiting current on the equipment grounding conductor with a future effective date.

Leviton Comment
Leviton manufactures electronic lighting control devices (like occupancy sensors) available with two wiring methods: 1- neutral required, 2- no neutral required. The no neutral solution does require an equipment grounding conductor and the device does push a very small amount of energy to the ground. As of Jan. 1 2020 these will only be allowed for retrofit or replacement applications. In Wiring Method #1, contractors should never use a device that requires a neutral in an application without a neutral. Using the ground as a neutral with these devices is dangerous as it pushes a higher amount of current to the ground. This could create a dangerous condition for personnel and potentially damage other equipment within the electrical system. For these reasons this practice is prohibited in this Code article.

Expert Analysis
This new section at 404.22 addresses the fact that electronic lighting control switches must be listed and “shall not introduce current on the equipment grounding conductor during normal operation.” This requirement has a future effective date of January 1, 2020, as well. When CMP-9 initiated 404.2(C) in the 2011 NEC, the intent was to begin a process that would ultimately result in no current being introduced intentionally onto the equipment grounding system as a result of the installation of electronic switching devices such as an occupancy sensor.

The new exception will recognize a retrofit installation or replacement situation in an existing situation where the grounded conductor is not installed. Electronic control switching devices that utilize the equipment grounding conductor for powering the device would still be permitted, but only in these retrofit applications. These products have been listed and in use for years. The product standard for these devices controls the amount of current permitted to be introduced on the equipment grounding conductor to no more than 0.5 mA. This exception will require devices that permit the use of the equipment grounding conductor for powering the electronics of the device to be listed and labeled for use in retrofit installations only where the grounded conductor is not provided in the switch device box or enclosure.