Daktronics DBH-150 - Manual (Page 13)

MECHANICAL INSPECTION
Inspection Schedule
Mechanical and electrical inspections shall be completed
in accordance with local regulations or every 5 years,
whichever comes sooner. Inspections shall be completed
by a competent person who is certified for field service.
All repairs shall also be inspected nd approved by a
competent person who is certified for field service prior
to the hoist being returned to service.
After usage over long periods of time, certain parts of
the Banner Hoist Assembly may become more audible
as certain components require periodical lubrication.
Examples of these parts of the assembly that could
end up requiring such inspection and maintenance
are shown on the illustrations to the left. Take into
consideration the environment of where the Banner Hoist
assembly will be installed to reduce the likelihood of
wear. On chain drives and acme parts, white lithium
grease should be used to lubricate (refer to
Figures 10-12).
Always ensure that when operating and performing
maintenance/inspection on the Banner Hoist system
that there is at least enough weight on the cables to
keep them taut. If the cables are allowed to become
slackened, the cable may become unwound from
the drum or for the cable to cross-over itself. Both
of these conditions present a safety hazard and will
depreciate the life of both the cable and the drum.
If a situation occurs where the cable has run over
the drum, simply lower the hoist to its lower limit and
pull the cabling outward, ensuring that the cabling
left on the drum is in line. Then with weight applied
raise the hoist to correctly rewind the cabling. Also
ensure that the cable is being correctly guided
through the Plastic Feed Guide (Figures 13,14)
while performing the rewinding. It may be necessary
to remove the front panel of the hoist to ensure
the cable is wound correctly on the drum. Should
additional problems or questions occur, do not
hesitate to call Daktronics for additional support.
Positioning of Drum Cable Keepers
Verify that the drum cable keepers are positioned
correctly as shown in Figure 15. The assemblies should
run parallel with the drum and contact the cables to
keep them in the drum grooves. If the plastic keeper part
is out of position, it should be relocated as shown. The
plastic keeper part is spring applied and should be free
to come off the drum. Lift the ends off the drum to ensure
the springs and resulting assembly are not binding.
Figure 10:
Drive Chain
9 MAINTENANCE/INSPECTION
Figure 11:
Cable Guide
Chain A Figure 12:
Cable Guide
Chain B
Figure 13: Cable Drum with Plastic Feed Guide
Figure 14: Cable Chain Clip
Figure 15: Drum Cable keepers