shall be in unbroken lengths.

(5) Supply Conductors Not Reduced in Size. Supply conductors not reduced in size under provisions of

520.53(H)(3) or (H)(4) shall be permitted to pass through holes in walls specifically designed for the purpose. If pen- etration is through the fire-resistant-rated wall, it shall be in accordance with 300.21.

(I) Cable Arrangement. Cables shall be protected by bushings where they pass through enclosures and shall be arranged so that tension on the cable is not transmitted to the connections. Where power conductors pass through metal, the requirements of 300.20 shall apply.

(J) Number of Supply Interconnections. Where connectors are used in a supply conductor, there shall be a maximum number of three interconnections (mated connector pairs) where the total length from supply to switchboard does not exceed 30 m (100 ft). In cases where the total length from supply to switchboard exceeds 30 m (100 ft), one

additional interconnection shall be permitted for each additional 30 m (100 ft) of supply conductor.

(K) Single-Pole Separable Connectors. Where single-pole portable cable connectors are used, they shall be listed and of the locking type. Sections 400.10, 406.6, and 406.7 shall not apply to listed single-pole separable connectors and single-conductor cable assemblies utilizing listed single-pole separable connectors. Where paralleled sets of current- carrying, single-pole separable connectors are provided as input devices, they shall be prominently labeled with a warning indicating the presence of internal parallel connections. The use of single-pole separable connectors shall comply with at least one of the following conditions:

(1) Connection and disconnection of connectors are pos- sible only where the supply connectors are interlocked to the source and it is not possible to connect or dis- connect connectors when the supply is energized.

(2) Line connectors are of the listed sequential-interlocking type so that load connectors shall be connected in the following sequence:

a. Equipment grounding conductor connection
b. Grounded circuit conductor connection, if provided c. Ungrounded conductor connection, and that discon
nection shall be in the reverse order
(3) A caution notice shall be provided adjacent to the line connectors indicating that plug connection shall be in the following order:
a. Equipment grounding conductor connectors
b. Grounded circuit conductor connectors, if provided c. Ungrounded conductor connectors, and that discon
nection shall be in the reverse order

(L) Protection of Supply Conductors and Connectors.

All supply conductors and connectors shall be protected against physical damage by an approved means. This pro- tection shall not be required to be raceways.

(M) Flanged Surface Inlets. Flanged surface inlets (recessed plugs) that are used to accept the power shall be rated in amperes.

(N) Terminals. Terminals to which stage cables are con- nected shall be located so as to permit convenient access to the terminals.

(0) Neutral Conductor.

(1) Neutral Terminal. In portable switchboard equipment designed for use with 3-phase, 4-wire with ground supply, the supply neutral terminal, its

associated busbar, or equivalent wiring, or both, shall have an ampacity equal to at least twice the ampacity of the largest ungrounded supply terminal.

Exception: Where portable switchboard equipment is specifically