WAC 296-150C-1250
Disconnecting means and branch circuit
protective equipment. (1) The branch circuit equipment may be
combined with the disconnecting means as a single assembly. Such a combination may be designated as a distribution
panelboard. If a fused distribution panelboard is used, the
maximum fuse size for the mains must be plainly marked with
lettering at least 1/4 inch high and visible when fuses are
changed.
Note:
See the National Electrical Code concerning identification of each disconnecting means and each feeder or branch
circuit at the point where it originated and type of marking needed.
(2) Plug fuses and fuseholders must be tamper-resistant,
Type "S," enclosed in dead-front fuse panelboards.
(3) A single disconnecting means must be provided in each
commercial coach. It must consist of a circuit breaker or a
switch, fuses, and their accessories installed in a readily
accessible location near the point of entrance of the supply
cord or conductors into the commercial coach. The main
circuit breakers or fuses must be plainly marked "main." This
equipment must contain a solderless type of grounding
connector or bar for the purposes of grounding, with
sufficient terminals for all grounding conductors. The
neutral bar termination of the grounded circuit conductors
must be insulated.
(4) The disconnecting equipment must have a rating
suitable for the connected load. The distribution equipment,
either circuit breaker or fused type, must be located a
minimum of twenty-four inches from the bottom of such
equipment to the floor level of the commercial coach. There
must be an accessible space of at least thirty inches wide by
thirty-six inches deep by seventy-eight inches high in front
of the electrical disconnect equipment. The main circuit
breakers or switches must be plainly marked "main." There
must be a label attached to the panelboard stating:
"This panelboard must be connected by a feeder assembly
having overcurrent protection rated at not more
than_____amperes." (The correct ampere rating must be marked
in the blank space.)
(5) Branch circuit distribution equipment must be
installed in each commercial coach and must include
overcurrent protection for each branch circuit consisting of
either circuit breakers or fuses.
(6) The branch circuit overcurrent devices must be rated:
(a) Not more than the circuit conductors; and
(b) Not more than one hundred fifty percent of the rating
of a single appliance rated ten amperes or more; but
(c) Not more than the overcurrent protection rating
marked on the motor-operated appliance. A device not approved
for branch circuit protection, such as a thermal cutout or
motor overload protective device, must not be considered as
the overcurrent device protecting the circuit.
(7) A 20-ampere fuse or circuit breaker must be
considered adequate protection for fixture leads, cords for
portable appliances and No. 14 AWG (American Wire Gauge) tap
conductors, not over six feet long, for recessed lighting
fixtures.
(8) If more than one outlet or load is on a branch
circuit, a 15-ampere receptacle must be considered protected
by a 20-ampere fuse or circuit breaker.
(9) When circuit breakers are provided for branch circuit
protection, 240-volt circuits must be protected by two-pole
common or companion trip circuit breakers.