OPERATING CONTROLS AND PROCEDURES RT770E OPERATOR MANUAL
3-36 Published 04-04-2017, Control # 446-09
Another section contains the notes for lifting capacities. Be
sure to read and understand all the notes concerning lifting
capacities.
The load chart also gives weight reductions for load handling
devices such as hook blocks, headache balls, boom
extensions, etc., which must be taken into consideration as
part of the load. Remember, the weight of any other load
handling devices such as chains, slings, or spreader bars
must be added to the weight of the load.
Proper Leveling of the Crane
ASME B30.5 specifies that if a crane is not level within 1% of
grade, the allowable capacities must be reduced. Therefore,
whether lifting on rubber or outriggers, it is essential that the
crane is level to within 1% of grade. The bubble level that is
provided on the crane is calibrated to be accurate within 1%
of grade.
To properly level the crane, the boom must be positioned
over the front of the crane, fully lowered to horizontal and
fully retracted (for cranes fitted with a boom rest, the boom
shall be stowed onto the rest). Raise and level the crane
using the outriggers; refer to Setting the Outriggers, page 3-
36.
A working crane may settle during lifting operations.
Frequently check the crane for level. When rechecking the
crane for level, the boom must be positioned over the front of
the crane, fully lowered to horizontal and fully retracted (for
cranes fitted with a boom rest, the boom shall be stowed
onto the rest). If necessary, relevel the crane using the
procedures under Setting the Outriggers, page 3-36.
Bubble Level Adjustment
The bubble level adjustment should be checked periodically;
if it is suspected that the bubble level indicator is out of
adjustment, verify and adjust the bubble level as follows:
1. Locate the crane on a firm, level surface.
2. Extend and set the outriggers. Level the crane, as
indicated by the bubble level indicator, using the
outriggers.
3. Place a miracle pointer level, carpenter level, or similar
type device on a machined surface such as the turntable
bearing or bearing mounting surfaces.
4. Using the outriggers, level the crane as indicated on the
leveling device used in step 3.
5. Using the bubble level indicator mounting screws, adjust
the bubble level indicator to show level.
Crane Functions
Setting the Outriggers
1. Engage the Parking Brake.
NOTE: The Parking Brake must be engaged to enable
outrigger functions.
2. Position the outrigger floats directly out from each
outrigger to where the outriggers will be properly
extended.
3. If extending the outrigger to the mid-extend or fully
extended position, depress the desired Extension
Switch on the Outrigger Selector Panel and hold the
Outrigger Extension/Retraction Switch to EXTEND. The
appropriate outrigger beam begins to extend. Refer to
Engaging the Mid-Extend Lock Pin, page 3-37 if the
crane is to be operated with any outrigger at the mid-
extend position.
NOTE: More than one outrigger beam can be extended at
a time. However, to ensure that each outrigger is
fully extended, repeat step 3 for each outrigger
after a multi-outrigger extension.
4. After deploying the four outrigger beams to one of the
three proper positions (fully retracted, mid-extend, fully
extended), depress the desired Stabilizer Switch on the
CAUTION
Possible Equipment Damage!
Always depress one of the outrigger/selector switches
before positioning the outrigger extension/retraction
switch to extend or retract. Failure to do this may cause a
hydraulic lock against the individual solenoid valves,
preventing them from opening.
DANGER
Electrocution Hazard!
To avoid death or serious injury, keep all parts of this
machine, the rigging, and materials being lifted at least 20
feet away from electrical power lines and equipment.
DANGER
Tipping Hazard!
All four outrigger beams must be deployed to one of three
positions before beginning operation, which include fully
retracted, mid-extend, or fully extended; do not operate
the crane with the outriggers in any other position.
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