2.17 HOOK RAISING/LOWERING OPERATION • With the boom deflection, the hoisted load slightly shifts forward. Notify the workers around such as slinging operators. • When hoisting a load, always stop hoisting once, when the load is raised above the ground. When such a practice is not exercised and the load is hoisted too quickly, that may cause a hazardous condition including breakage of the machine or tipping of it. • When the hook block is over-wound, such condition is detected as an over hoist and operations including winching up, boom telescoping or boom raising are interrupted, as well as the Over hoist and moment limiter alarm buzzer beeps. When the buzzer beeps, immediately release control levers such as winch lever, boom telescoping lever or boom derricking lever to the NEUTRAL position so that all the crane operations are discontinued. • When lowering the hook for long distance for underground works, be sure to leave more than three turns of the wire rope on the winch drum.
CAUTION Do not let the hook block touch the ground. The winch drum will wind irregularly, damaging the wire rope. Operate the winch lever (3) as follows; • Lower: Push the lever forward to the “DOWN” side. • Neutral: Release your hand from the lever. The lever will return to the NEUTRAL position and the raising/lowering of the hook block stops. • Raise: Pull the lever toward you to the “UP” side.
NOTES Adjust the winch raising/lowering speed with the winch lever and stroke of the acceleration lever.
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