bushings or equivalent. The cord assembly shall have permanent provisions for protection against corrosion and mechanical damage while the unit is in transit.

(B) Cord Length. The cord-exposed usable length shall be measured from the point of entrance to the park trailer or the face of the flanged surface inlet (motor- base attachment plug) to the face of the attachment plug at the supply end.

The cord-exposed usable length, measured to the point of entry on the unit exterior, shall be a minimum of 7.0 m (23 ft) where the point of entrance is at the side of the unit, or shall be a minimum 8.5 m (28 ft) where the point of entrance is at the rear of the unit. The maximum length shall not exceed 11 m (36'/2 ft).
Where the cord entrance into the unit is more than
900 mm (3 ft) above the ground, the minimum cord
lengths above shall be increased by the vertical distance
of the cord entrance heights above 900 mm (3 ft).

(C) Attachment Plugs.

(1) Units with Two to Five 15- or 20-Ampere Branch

Circuits. Park trailers wired in accordance with

552.46(A) shall have an attachment plug that shall be 2-
pole, 3-wire grounding-type, rated 30 amperes, 125
volts, conforming to the configuration shown in Figure
552.44(C) intended for use with units rated at 30
amperes, 125 volts.
FPN: Complete details of this configuration can be found in ANSI/NEMA WD 6-1989, National Electrical Manufacturers Association's Standard for Dimensions of Attachment Plugs and Receptacles, Figure TT.

(2) Units with 50-Ampere Power Supply Assembly. Park trailers having a power-supply assembly rated 50 amperes as permitted by 552.43(B) shall have a 3-pole,

4-wire grounding-type attachment plug rated 50 amperes, 125/250 volts, conforming to the configuration
shown in Figure 552.44(C).
FPN: Complete details of this configuration can be found in ANSI/NEMA WD 6-1989, National Electrical Manufacturers Association Standard for Dimensions of Attachment Plugs and Receptacles, Figure 14-50.
(D) Labeling at Electrical Entrance. Each park trailer shall have permanently affixed to the exterior skin, at or near the point of entrance of the power-supply assembly, a label 75 mm x 45 mm (3 in. x PA in.) minimum size, made

Receptacles Caps

Exception: Where the panelboard cover is exposed to the inside aisle space, one of the working clearance dimensions shall be permitted to be reduced to a minimum of 550 mm (22 in.). A panelboard shall be considered exposed where the panelboard cover is within 50 mm (2 in.) of the aisle's finished surface.

(C) Dead-Front Type. The distribution panelboard shall be of the dead-front type. A main disconnecting means shall be provided where fuses are used or where more

than two circuit bre
kers are employed. A main

50-A.125/250-V, 3-pole, 4-wire, grounding type

Figure 552.44(C) Attachment Cap and Receptacle

Configurations.

of etched, metal-stamped, or embossed brass, stainless steel, or anodized or alclad aluminum not less than 0.51 mm (0.020 in.) thick, or other suitable material [e.g.,
0.13 mm (0.005 in.) thick plastic laminate], that reads, as appropriate, either
THIS CONNECTION IS FOR 110-125-VOLT AC, 60 HZ,