Maeda LC1385M-8BF - Boom Telescoping Operation

3-154
3.20 BOOM TELESCOPING OPERATION
• Operate the left working equipment control lever as slowly as possible. Sudden lever
operation especially while hoisting a load will cause the load to swing, giving a great impact to
the machine, and thus may break the crane or overturn the machine.
• Never attempt a practice to draw a load forward or set a laying load upright by boom
telescoping. Such practice must be attained by hook block hoisting.
• Extending the boom increases the working radius and the rated total load that can be hoisted
decreases. Be extremely careful so that the load weight will not be overloaded with the boom
most extended when working by telescoping the boom.
• When the boom is extended, the hook block is raised. If the alarm buzzer of the over hoist
detector is heard during the boom extending operation, return the left working equipment
control lever immediately to the NEUTRAL position and stop the boom extending operation.
CAUTION
• The hook block is raised or lowered while telescoping the
boom. Perform the winch operation at the same time to
adjust the hook block height.
• When the boom is maintained extended for a long time,
the boom slightly retracts due to the temperature change
in the hydraulic oil. In this case, extend the boom as
needed.
Perform the left work equipment control lever (1) as follows.
• Extend: Push the lever forward.
• Neutral: Release your hand from the lever.
The lever returns to the NEUTRAL position and the boom
telescoping stops.
• Retract: Pull the lever toward you.
NOTES
• Adjust the boom telescoping speed with the left work
equipment control lever (1) and the stroke of the acceleration
pedal (2).
• When the boom extends, the second boom extends first, and
the third boom extends next, then fourth and fifth boom extend
together at the same time. When the boom retracts, it retracts
in the reverse order of extending the boom.
CAUTION
As the boom extends and the hook block (3) hoists the
weight (5) of the over-winding protector (4), the boom
extension stops. When the hook has hoisted the weight of
the over-winding protector, performing extending operation
does not extend the boom. In this case, lower the hook.