Belden Hirschmann HC4900, User Manual

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7.5 Length cable retract un-smoothly
Sometimes when the boom is retracted, the length cable cannot return to the
original position naturally or retract not smoothly. This is because that the
coil-spring pre-tension is too low or the length cable in the cable reel has fallen
off.
Please pre-tighten the length cable several circles to solve the problem:
1) Retract the boom and put it on the rack
2) Draw back the tip of the cable from the tip of the boom and retract to the
cable reel.
3) Pre-tight the cable reel (turn the cable reel to the cable out direction, the
length cable and the cable reel shall turn together) and make sure the
cable can be pulled out and retracted smoothly.
4) Pull out the cable and fix it on the tip of the boom at the original place.
5) After pre-tight the cable reel the display of the boom length will be affected,
please adjust the length sensor till the displayed value equal to the actual
length.
7.6 Question and Answer
1. Why the OM setting is correct but the current rated load is different with
the performance diagram of manufacture (the parameter are all normal)?
Answer: Possible reason is your reeving setting is different with actual
data. E.g. current performance shows the rated load is 20T and
reeving setting is 1. But because the largest load for single steel
cable is 4T, the rated load displayed on central unit is 4T.
Operators shall be very cautious for the above adjustment. Any incorrect
action may seriously affect the crane and the operation. And after finish the
adjustment, please confirm once again before start to work.
CAUTION