WAC 296-24-23513
Electric equipment. (1) General.
(a) Wiring and equipment shall comply with chapter 296-24
WAC Part L, and WAC 296-800-280.
(b) The control circuit voltage shall not exceed 600 volts
for a.c. or d.c. current.
(c) The voltage at pendant pushbuttons shall not exceed 150
volts for a.c. and 300 volts for d.c.
(d) Where multiple conductor cable is used with a suspended
pushbutton station, the station shall be supported in a manner
that will protect the electrical conductors against strain.
(e) Pendant control boxes shall be constructed to prevent
electrical shock and shall be clearly marked for identification
of functions.
(2) Equipment.
(a) Electrical equipment shall be so located or enclosed
that live parts will not be exposed to accidental contact under
normal operating conditions.
(b) Electric equipment shall be protected from dirt, grease,
oil, and moisture.
(c) Guards for live parts shall be substantial and so
located that they cannot be accidentally deformed so as to make
contact with the live parts.
(3) Controllers.
(a) Cranes not equipped with spring-return controllers or
momentary contact pushbuttons shall be provided with a device
which will disconnect all motors from the line on failure of
power and will not permit any motor to be restarted until the
controller handle is brought to the "off" position, or a reset
switch or button is operated.
(b) Lever operated controllers shall be provided with a
notch or latch which in the "off" position prevents the handle
from being inadvertently moved to the "on" position. An "off"
detent or spring return arrangement is acceptable.
(c) The controller operating handle shall be located within
convenient reach of the operator.
(d) As far as practicable, the movement of each controller
handle shall be in the same general directions as the resultant
movements of the load.
(e) The control for the bridge and trolley travel shall be
so located that the operator can readily face the direction of
travel.
(f) For floor-operated cranes, the controller or controllers
if rope operated, shall automatically return to the "off"
position when released by the operator.
(g) Pushbuttons in pendant stations shall return to the off
position when pressure is released by the crane operator.
(h) Automatic cranes shall be so designed that all motions
shall fail-safe if any malfunction of operation occurs.
(i) Remote-operated cranes shall function so that if the
control signal for any crane motion becomes ineffective the crane
motion shall stop.
(4) Resistors.
(a) Enclosures for resistors shall have openings to provide
adequate ventilation, and shall be installed to prevent the
accumulation of combustible matter near hot parts.
(b) Resistor units shall be supported so as to be free as
possible from vibration.
(c) Provision shall be made to prevent broken parts or
molten metal falling upon the operator or from the crane.
(5) Switches.
(a) The power supply to the runway conductors shall be
controlled by a switch or circuit breaker located on a fixed
structure, accessible from the floor, and arranged to be locked
in the open position.
(b) On cab-operated cranes a switch or circuit breaker of
the enclosed type, with provision for locking in the open
position shall be provided in the leads from the runway
conductors. A means of opening this switch or circuit breaker
shall be located within easy reach of the operator.
(c) On floor-operated cranes, a switch or circuit breaker of
the enclosed type, with provision for locking in the open
position, shall be provided in the leads from the runway
conductors. This disconnect shall be mounted on the bridge or
footwalk near the runway collectors. One of the following types
of floor operated disconnects shall be provided:
(i) Nonconductive rope attached to the main disconnect
switch.
(ii) An undervoltage trip for the main circuit breaker
operated by an emergency stop button in the pendant pushbutton
station.
(iii) A main line contactor operated by a switch or
pushbutton in the pendant pushbutton station.
(d) The hoisting motion of all electric traveling cranes
shall be provided with an overtravel limit switch in the hoisting
direction.
(e) All cranes using a lifting magnet shall have a magnet
circuit switch of the enclosed type with provision for locking in
the open position. Means for discharging the inductive load of
the magnet shall be provided.
(6) Runway conductors. Conductors of the open type mounted
on the crane runway beams or overhead shall be so located or so
guarded that persons entering or leaving the cab or crane
footwalk normally could not come into contact with them.
(7) Extension lamps. If a service receptacle is provided in
the cab or on the bridge of cab-operated cranes, it shall be a
grounded three-prong type permanent receptacle, not exceeding 300
volts.
(8) Floor operated cranes.
(a) An unobstructed aisle not less than three feet wide
shall be maintained for travel of the operator except in such
cases where the control handles are hung from the trolleys of
traveling cranes.
(b) The handles of control ropes shall be distinctly
different in contour so that, without looking, the operator will
know which is the hoisting and which is the lowering handle. The
direction of all movements of the crane shall be clearly
indicated in some manner so that the operator can easily become
familiar with them.
(c) When repairing runways, repairpersons shall place rail
stops and warning signs or signals so as to protect both ends of
the section to be repaired.
(d) Repairpersons shall take care to prevent loose parts
from falling or being thrown upon the floor beneath.
[Statutory Authority: RCW 49.17.010, [49.17].040, and[49.17].050
. 01-11-038, § 296-24-23513, filed 5/9/01, effective
9/1/01. Statutory Authority: Chapter 49.17 RCW. 91-24-017
(Order 91-07), § 296-24-23513, filed 11/22/91, effective
12/24/91; Order 73-5, § 296-24-23513, filed 5/9/73 and Order
73-4, § 296-24-23513, filed 5/7/73.]