In 2020 the National Electric Code (NEC) was updated to include new guidance on services that include more than one disconnecting means. The new code revision clarifies how many disconnects are allowed and where they may be mounted. The changes will have ramifications when new electrical services are designed and installed.
Article 230.71: The New Six Disconnect Rule
NEC 2020 article 230.71(B) states:
Two to six service disconnects shall be permitted for each service permitted by 230.2 for each set of service-entrance conductors permitted by 230.40 Exception No. 1,3,4 or 5. The two to six service disconnecting means shall be permitted to consist of a combination of any of the following:
1. Separate enclosures with a main service disconnecting means in each enclosure
2. Panelboards with a main service disconnecting means in each panelboard enclosure
3. Switchboard(s) where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section
4. Service disconnects in switchgear or metering centers where each disconnect is located in a separate compartment
Article 230.71: What Changed?
The significant change in article 230.71 regards the separate enclosures or sections for each disconnect. Before the code change, it was possible to have more than one disconnect per enclosure or switchboard section, which saved space within electrical installation.
Now, each disconnect must be mounted on its own switchboard section or enclosure. These sections must be isolated from each other with vertical barriers.
How the New Six Disconnect Rule Affects Electromechanical Installations
The new disconnect rule changes will increase the amount of real estate needed to house a property’s service entrance equipment. Switchboard sections are large by design, and increasing the number of sections required will increase the switchboard’s footprint.
Architects and contractors will need to take this enlarged footprint into account during the design stage to avoid costly changes down the road. Electromechanical professionals should share the new code requirements with property owners and their architectural and engineering teams and help them understand the impact the code change will have on their projects.
Prior to the new NEC 2020 requirements, six disconnect services were often installed because they provided a good value to the building owner. With the new requirements, a single section six disconnect board could be changed to a board with a main section and a distribution section. This will result in a smaller footprint and most likely a more cost-effective solution, especially for boards with more than two mains.
A consultative approach is what the experts at EMI deliver to our customers every day. For more information on the new six disconnect rule and how it may affect your building, contact EMI today.