MHS Boilers CRUZ belt, Инструкция по установке, эксплуатации и обслуживанию, Страница: 13 / 46

CRUZbelt
13
E0032544Rev090710
OPERATOR CONTROLS:
Additional operator controls should be designed into
the system with the same guidelines that go into
start and stop pushbuttons. Devices which are
repeated on multiple control stations, such as
emergency stops, should be located at the same
relative location on each station. All operator
controls shall be clearly marked or labeled to
indicate the function controlled.
EMERGENCY STOPS:
All locations where an operator must work directly at
the conveyor should be protected by an emergency
stop. Operators should not have to leave their
position to actuate the emergency stop.
Conveyor in areas of high pedestrian traffic should
also be protected by emergency stop devices.
Emergency stops should be located throughout a
system. Their location will depend on likely
observation points and areas with special devices or
interfaces between equipment.
Emergency stops can be a pushbutton or cable
operated switch. The pushbutton should be
mushroom-style and red. The pushbutton must
require resetting after actuation. Cable operated
switches should trip by pulling the cable and require
resetting at the switch.
An emergency stop should normally stop all
conveyors in the system. Very large systems may
involve dividing the system into zones of control.
Actuating an emergency stop must drop out the start
circuit and require restarting the system using the
start pushbutton.
WARNING
Before restarting a conveyor which has been
stopped because of an emergency, an inspection of
the conveyor shall be made and the cause of the
stoppage determined. The starting device shall be
locked out before any attempt is made to correct the
cause of the stoppage.
CONTROLS LOGIC:
Solid state controls logic devices, such as
programmable controllers, are used extensively for
conveyor control. They are very reliable, but a
hardware failure or software bug could cause an
output to malfunction. For this reason, start circuits,
warning horn circuits, and emergency stops should
usually be configured using conventional relay logic.
SAFETY SWITCHES:
All conveyor control cabinets and motors should be
provided with safety (or disconnect) switches.
These switches must have provisions for padlocking.
As required for maintenance, equipment should be
locked in the OFF position.
SPECIAL DEVICES:
Special devices and equipment such as vertical lifts,
turntables, high speed conveyors etc. all have
unique design and safety requirements and should
be evaluated individually.