424.19 Disconnecting Means. Means shall be provided to
simultaneously disconnect the heater, motor controller(s),
and supplementary overcurrent protective device(s) of all
fixed electric space-heating equipment from all ungrounded
conductors. Where heating equipment is supplied by more
than one source, the disconnecting means shall be grouped
and marked. The disconnecting means specified in
424.19(A) and (B) shall have an ampere rating not less than
125 percent of the total load of the motors and the heaters.
The provision for locking or adding a lock to the disconnecting
means shall be installed on or at the switch or
circuit breaker used as the disconnecting means and shall
remain in place with or without the lock installed.
(A) Heating Equipment with Supplementary Overcurrent
Protection. The disconnecting means for fixed electric
space-heating equipment with supplementary overcurrent
protection shall be within sight from the supplementary
overcurrent protective device(s), on the supply side of these
devices, if fuses, and, in addition, shall comply with either
424.19(A)(1) or (A)(2).
(1) Heater Containing No Motor Rated over 1⁄8 Horsepower.
The above disconnecting means or unit switches
complying with 424.19(C) shall be permitted to serve as the
required disconnecting means for both the motor controller(
s) and heater under either of the following conditions:
(1) The disconnecting means provided is also within sight
from the motor controller(s) and the heater.
(2) The disconnecting means provided is capable of being
locked in the open position.
(2) Heater Containing a Motor(s) Rated over 1⁄8 Horsepower.
The above disconnecting means shall be permitted
to serve as the required disconnecting means for both the
motor controller(s) and heater by one of the following
means:
(1) Where the disconnecting means is also in sight from
the motor controller(s) and the heater.
(2) Where the disconnecting means is not within sight
from the heater, a separate disconnecting means shall
be installed, or the disconnecting means shall be capable
of being locked in the open position, or unit
switches complying with 424.19(C) shall be permitted.
(3) Where the disconnecting means is not within sight
from the motor controller location, a disconnecting
means complying with 430.102 shall be provided.
(4) Where the motor is not in sight from the motor controller
location, 430.102(B) shall apply.
