230.75 Disconnection of Grounded Conductor.
Code Change Summary: Deleted text on neutral disconnect link, and a new informational note.
NEC Section 230.75 provides information on disconnecting the grounded conductor at a service. This means of grounded conductor disconnection is commonly referred to by manufacturers as the “neutral disconnect link”.
Most service disconnecting means only disconnect the ungrounded conductors rather than the grounded conductor in compliance with 230.74.
According to 230.75, where the service disconnecting means does not disconnect the grounded conductor from the premises wiring, other means shall be provided for this purpose within the service equipment. This is usually done via a neutral disconnect link (see image).
In the 2017 NEC®, the last sentence in 230.75 permitted the neutral disconnect link to be located in any section of a multisection switchboard or switchgear if the switchboard or switchgear section was marked to indicate the neutral disconnect link was located within. This is an important marking for the electrical inspector who often searches through many switchboard sections for the presence of a properly installed and torqued neutral disconnect link.
In the 2020 NEC®, a proposal was accepted to simply add a new informational note explaining more about the term “neutral disconnect link” but somehow in the process of adding the informational note, the last sentence in 230.75 was deleted. It will likely return in the 2023 NEC® once the mistake has been realized.
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 2020 NEC® edition of NFPA 70.
2017 Code Language:
230.75 Disconnection of Grounded Conductor. Where the service disconnecting means does not disconnect the grounded conductor from the premises wiring, other means shall be provided for this purpose in the service equipment. A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted for this purpose. In a multisection switchboard or switchgear, disconnects for the grounded conductor shall be permitted to be in any section of the switchboard or switchgear, if the switchboard or switchgear section is marked to indicate a grounded conductor disconnect is located within.
2020 Code Language:
230.75 Disconnection of Grounded Conductor. Where the service disconnecting means does not disconnect the grounded conductor from the premises wiring, other means shall be provided for this purpose in the service equipment. A terminal or bus to which all grounded conductors can be attached by means of pressure connectors shall be permitted for this purpose. In a multisection switchboard or switchgear, disconnects for the grounded conductor shall be permitted to be in any section of the switchboard or switchgear.
Informational Note: In switchgear or multisection switchboards, the disconnecting means provided for the grounded conductor is typically identified as a neutral disconnect link and is typically located in the bus to which the service grounded conductor is connected.