230.71(B) Two to Six Service Disconnecting Means.

Some service disconnecting means configurations permitted in 2023 NEC Section 230.71(B).
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Some service disconnecting means configurations permitted in 2023 NEC Section 230.71(B).

Code Change Summary: Revised code language on allowable service configurations.

The NEC® permitted up to six service disconnects in a single enclosure for decades. During the 2020 NEC® code development process, Section 230.71(B) was changed to no longer allow this configuration since there are still energized conductor terminals and busbars in the service enclosure even when all service disconnects are switched off.

Basically, the only way to establish an electrically safe work condition with this old configuration (in order to perform work in the service enclosure), is to have the electric utility company de-energize the service.

In the 2020 NEC®, Section 230.71 was changed to require each service to have only one disconnecting means unless the requirements of 230.71(B) were met which provided four specific service disconnect configurations:

  1. Separate enclosures with a main service disconnect in each enclosure (see image of service B).
  2. Panelboards with a main service disconnect in each panelboard enclosure (see image of service C).
  3. Switchboards where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section (see image of service D).
  4. Service disconnects in switchgear or metering centers where each disconnect is located in a separate compartment.

In the 2023 NEC® Section 230.71(B) was taken a step further:

Items 1 and 2 from Section 230.71(B) above remain unchanged.

Item 3 above still stands but was reworded to allow switchboard configurations with only one service disconnect in each separate vertical section with barriers between each vertical section that maintain the required inadvertent contact protection specified in Section 230.62 based on access from the adjacent sections.

Item 4 above now includes transfer switches where each disconnect is located in a separate compartment.

Items 5, 6, the exception, and informational note 3 (not shown) are all new:

  1. Metering centers that have a main service disconnect in each metering center (see image of service A).
  2. Motor control centers having only one service disconnect in a motor control center unit, or a maximum of two service disconnects (which aligns with exception 1 in Section 430.95) in a single motor control center with barriers between each motor control center unit or compartment containing a service disconnect, which maintains the inadvertent contact protection requirement in Section 230.62 based on access from adjacent motor control center units or compartments.

The new exception applies to items (2), (3), (4), (5), and (6). This exception permits existing service equipment, installed in compliance with previous editions of the NEC® that allowed multiple service disconnects in a single enclosure, section, or compartment, to be permitted to have a maximum of six service disconnecting means.

Below is a preview of the NEC®. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2023 NEC® edition of NFPA 70.

2020 Code Language:

230.71(B) Two to Six Service Disconnecting Means. Two to six service disconnects shall be permitted for each service permitted by 230.2 or 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

2023 Code Language:

230.71(B) Two to Six Service Disconnecting Means. Two to six service disconnects shall be permitted for each service permitted by 230.2 or 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 with barriers provided between each vertical section to maintain the inadvertent contact protection required in 230.62 based on access from the adjacent section(s)

(4) Service disconnects in switchgear, transfer switches, or metering centers where each disconnect is located in a separate compartment

(5) Metering centers with a main service disconnecting means in each metering center

(6) Motor control center(s) where there is only one service disconnect in a motor control center unit and a maximum of two service disconnects provided in a single motor control center with barriers provided between each motor control center unit or compartment containing a service disconnect to maintain the inadvertent contact protection required in 230.62 based on access from adjacent motor control center unit(s) or compartment(s)

Exception to (2), (3), (4), (5), and (6): Existing service equipment, installed in compliance with previous editions of this Code that permitted multiple service disconnecting means in a single enclosure, section, or compartment, shall be permitted to contain a maximum of six service disconnecting means.

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230.71(B) Two to Six Service Disconnecting Means.

Below is a Real Question from our Electrical Continuing Education Courses for Electrical License Renewal:

Based on the 2023 NEC, which of the following is true of Section 230.71(B)?

A: Metering centers that have a main service disconnect in each metering center are permitted.
B: Items 1 and 2 from Section 230.71(B) were deleted in the 2023 NEC.
C: Items 3 and 4 from Section 230.71(B) were deleted in the 2023 NEC.
D: There are NO exceptions in Section 230.71(B) for existing installations.
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