Manitowoc Grove GRT8120, Operator'S Manual

Page: 111 / 448

Grove
Published 3-22-2021, Control # 702-02
3-37
GRT8120 OPERATOR MANUAL OPERATING CONTROLS AND FEATURES
3
Buzzer
The buzzer (8, Figure 3-17) comes on when one or more of
the following conditions exist:
• Park brake not released when transmission is in F or R
• Engine alarms
• Emergency Stop Switch activated
• Low brake pressure
• High hydraulic oil temperature
• High transmission oil temperature
• Low steer pressure condition (CE Certified cranes)
• Hoist 3rd wrap condition
• Anti-two-Block condition
• Rated Capacity Limiter (RCL) lockout condition
Maintained Limit Bypass Switch (Non-CE
Certified Cranes)
T h e R a t e d C a p a c i t y L i m i t e r ( R C L ) s y s t e m , w h e n
programmed accurately, will lock out the following crane
functions—boom up/down, telescope extend, and hoist up—
when a lift is attempted at or above crane capacity, or when a
two-block condition exists.
Locking out these functions prevents the overload or
two-block condition from worsening.
The Rear Maintained Limit Bypass Switch (9, Figure 3-17) is
a two-position, maintained type key switch located behind
the operator seat.
During maintenance or troubleshooting work, or to recover
the crane, turn switch clockwise to bypass the following
limiter systems and their crane function lockouts:
• RCL System (boom up/down, telescope extend, hoist
up)
• Anti-Two-Block System (boom up/down, telescope
extend, hoist up)
• 3rd Wrap Limiter System (hoist down)
• Working Range Limiter (WRL) System
• Carrier Avoidance System
• -29°C Temperature Limiter System (optional)
The following indicators come on to indicate the limiters are
bypassed:
• Bypass 3 Pressed Indicator is on (Figure 4-206)
• RCL Bypass Active Indicator is on (Figure 4-206)
• RCL Shutdown Warning Indicator is flashing
(5, Figure 3-6)
• Anti-two-block Indicator is flashing (7, Figure 3-6)
• 3rd Wrap Alert is flashing (Figure 4-68)
• Working Range Limiter (WRL) Indicator is flashing
(Figure 4-71)
• Low Boom Angle Alert is flashing (Figure 4-68)
• -29°C Temperature Limiter Alert is flashing (Figure 4-68)
All craning functions locked out are bypassed while key
switch is in the clockwise position.
Overriding the RCL with this switch should only be done by a
qualified operator or technician.
NOTE: Before powering up the crane, make sure the RCL
Override Switch is in the Normal (not Override)
position to prevent an error code from being
generated.
WARNING
Overload Hazard!
The Limit Bypass Switch prevents the function lockouts
from activating.
When the Limit Bypass Switch is activated, the operator
must make sure that the crane is not overloaded.
Do not operate the crane with the RCL overridden during
normal operations.