408 – Switchboards, Switchgear, and Panelboards

408.4(A) – Approved Locations for Circuit Directory for a Panelboard

Change at a Glance:

Revisions were made to allow the circuit directory for a panelboard to be located in an “approved location adjacent” to the panelboard door.

408.4 Field Modification Required. (Switchboards, Switchgear, and Panelboards)

(A) Circuit Directory or Circuit Identification.
Every circuit and circuit modification shall be legibly identified as to its clear, evident, and specific purpose or use. The identification shall include an approved degree of detail that allows each circuit to be distinguished from all others. Spare positions that contain unused overcurrent devices or switches shall be described accordingly. The identification shall be included in a circuit directory that is located on the face or, inside of, or in an approved location adjacent to the panel door in the case of a panelboard and at each switch or circuit breaker in a switchboard or switchgear. No circuit shall be described in a manner that depends on transient conditions of occupancy.

408.6 – Short-Circuit Current Ratings of Switchboards, Switchgear, and Panelboards

Change at a Glance:

New requirement added to Article 408 requiring available fault current and date calculation was performed to be field marked on the enclosure at the point of supply for switchboards, switchgear, and panelboards (other than dwelling units).

408.6 Short-Circuit Current Rating. (Switchboards, Switchgear, and Panelboards)

Switchboards, switchgear, and panelboards shall have a short-circuit current rating not less than the available fault current. In other than one- and two-family dwelling units, the available fault current and the date the calculation was performed shall be field marked on the enclosure at the point of supply. The marking shall comply with 110.21(B)(3).

408.8 – Reconditioning of Equipment. (Switchboards, Switchgear, and Panelboards)

Change at a Glance:

New section added to address reconditioning of panelboards (No) and switchboards and switchgear (Yes).

408.8 Reconditioning of Equipment. (Switchboards, Switchgear, and Panelboards)

Reconditioning of equipment within the scope of this article shall be limited as described in 408.8(A) and (B). The reconditioning process shall use design qualified parts verified under applicable standards and be performed in accordance with any instructions provided by the manufacturer. If equipment has been damaged by fire, products of combustion, or water, it shall be specifically evaluated by its manufacturer or a qualified testing laboratory prior to being returned to service.

(A) Panelboards. Panelboards shall not be permitted to be reconditioned. This shall not prevent the replacement of a panelboard within an enclosure. In the event the replacement has not been listed for the specific enclosure and the available fault current is greater than 10,000 amperes, the completed work shall be field labeled, and any previously applied listing marks on the cabinet that pertain to the panelboard shall be removed.

(B) Switchboards and Switchgear. Switchboards and switchgear, or sections of switchboards or switchgear, shall be permitted to be reconditioned. Reconditioned switchgear shall be listed or field labeled as reconditioned, and previously applied listing marks, if any, within the portions reconditioned shall be removed.

408.18(C) – Clearances for Switchboards, Switchgear, and Panelboards)

Change at a Glance:

New provision will require switchboards and switchgear requiring rear or side access to be marked (by manufacturer) on the front of said equipment indicating rear or side access is needed. Existing 408.3(D) was moved to new 408.18(C) to intensify the requirement that grounded and grounding terminals be installed such that it is not necessary to reach across ungrounded bus or terminal(s) to make connections.

408.18 Clearances (Switchboards, Switchgear, and Panelboards)

(C) Connections. Each section of equipment that requires rear or side access to make field connections shall be so marked by the manufacturer on the front. Section openings requiring rear or side access shall comply with 110.26. Load terminals for field wiring shall comply with 408.18(C)(1), (C)(2), or (C)(3) as applicable.
(1) Equipment Grounding Conductors. Load terminals for field wiring, including grounded circuit conductor load terminals and connections to the equipment grounding conductor bus for load equipment grounding conductors, shall be so located that it is not necessary to reach across or beyond an uninsulated ungrounded bus in order to make connections.
(2) Grounded Circuit Conductors. Where multiple branch or feeder grounded circuit conductor load terminals for field wiring are grouped together in one location, they shall be so located that it is not necessary to reach across uninsulated ungrounded bus, whether or not energized, in order to make connections. Where only one branch or feeder set of load terminals for field wiring are grouped with its associated ungrounded load terminals, they shall be so located that it is not necessary to reach across energized uninsulated bus including other branch or feeder bus in order to make connections. Bus on the line side of service, branch, or feeder disconnects is considered energized with respect to its associated load side circuits.
(3) Ungrounded Conductors. Load terminals for ungrounded conductors shall be so located that it is not necessary to reach across energized uninsulated bus in order to make connections. Bus on the line side of service, branch, or feeder disconnects is considered energized with respect to its associated load side circuits.

408.36, Ex. No. 1 – Overcurrent Protection in Panelboards

Change at a Glance:

Panelboards were generally required to be provided with individual overcurrent protected having a rating not greater than that of the panelboard. This overcurrent protective device could be located within the panelboard itself or at any point on the supply side of the panelboard. An exception to this rule gave permission to exclude this individual overcurrent protection if the panelboard was being used as service equipment with up to six means of disconnect as permitted by 230.71.

408.36 Overcurrent Protection (Panelboards)

In addition to the requirement of 408.30, a panelboard shall be protected by an overcurrent protective device having a rating not greater than that of the panelboard. This overcurrent protective device shall be located within or at any point on the supply side of the panelboard.
Exception No. 1: Individual protection shall not be required for a panelboard used as service equipment with multiple disconnecting means in accordance with 230.71. In panelboards protected by three or more main circuit breakers or sets of fuses, the circuit breakers or sets of fuses shall not supply a second bus structure within the same panelboard assembly.
Exception No. 2 1: Individual protection shall not be required for a panelboard protected on its supply side by two main circuit breakers or two sets of fuses in other than service equipment, having a combined rating not greater than that of the panelboard. A panelboard constructed or wired under this exception shall not contain more than 42 overcurrent devices. For the purposes of determining the maximum of 42 overcurrent devices, a 2-pole or a 3-pole circuit breaker shall be considered as two or three overcurrent devices, respectively.
Exception No. 3 2: For existing panelboards, individual protection shall not be required for a panelboard used as service equipment for an individual residential occupancy.

408.43 – Panelboard Orientation

Change at a Glance:

New section added to prohibit panelboards from being installed in a face-up position.

408.43 Panelboard Orientation.

Panelboards shall not be installed in the face-up position.