Tadano GT-550E-2, Руководство по эксплуатации и обслуживанию

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[NOTICE]
◆
While the elevating cylinder is extended or retract-
ed to the full stroke, the display of the AML becomes
erroneous. In this case, elevate the boom in the op-
posite direction to terminate the stroke end
condition.
Configuration and Functions of the
AML System
The AML (Automatic Moment Limiter) system is a safety
device provided to prevent overloading of the crane
which may cause it to overturn or be damaged.
The AML system has various kinds of functions, includ-
ing the following four typical functions. Based on the
registered work conditions by operator selection and the
signals from various sensors, the crane operations are
controlled.
(1) Automatic stop function for overloading
The AML calculates and compares the working and
rated moment values and displays them as a per-
centage. When the working moment exceeds the
rated moment (100% or more), failure message is
shown, alarm buzzer sounds, and the crane opera-
tion toward the critical side stops.
(2) Automatic stop function by boom upper angle restric-
tion
To prevent jib from contacting the hook block or wire
rope during boom lift or single top lift, a message and
an alarm is output and boom raising and boom re-
traction are halted in the following conditions:
• The boom is raised over approx. 76
°
while the
boom extension is less than approx. 2 m.
• The boom extension is reduced less than approx. 2
m while the boom angle is over approx. 76°.
(3) Working range limit functions
When any working range limit is registered to AML,
the crane is controlled so that the crane work posture
does not exceed this registered working range limit.
When the boom reaches the previously registered re-
striction, buzzer sounds, and the crane operation
stops.
(4) Slow stop function
The elevating speed slows down before the boom
stops slowly in the following conditions:
• Boom (lowering) stopping by overloading
• Boom (raising) stopping by boom upper angle re-
striction
• Boom reaches the stroke end (while raised and
lowered)
• Boom (raising and lowering) stopping by working
range limit function
T038300E
25
AML (Overload Prevention Device) AML (Overload Prevention Device)
• When the crane is automatically stopped during
operation toward critical condition (hoisting up,
boom extension or boom lowering), operate the
appropriate controls to move toward the non-
critical condition (hoist down, retract boom or
raise boom).
• Do not raise the boom to raise the load clear of
the ground. Doing so is dangerous because the
crane will not stop automatically even when it is
overloaded. Hoist up the load to raise it clear of
the ground. Once the load has cleared the
ground, stop hoisting and check for safety.
Configuration and Functions of the
AML System
Automatic stop function for overloading
Automatic stop function by boom upper angle restric-
tion
• The boom is raised over approx. 76
°
while the
boom extension is less than approx. 2 m.
• The boom extension is reduced less than approx. 2
m while the boom angle is over approx. 76°.
Slow stop function