Accessory Circuits; Anti-Double Blocking System (Figure 3-6) - Manitowoc Grove 5540F Service Manual

5540F/YB5515 SERVICE MANUAL

ACCESSORY CIRCUITS

Anti-Double Blocking System (Figure 3-6)

General
This mechanism inhibits the hook block from being pulled
into the boom head during extension of the booms and
during winch operation. When the hook block actuates the
limit switch on the boom head, oil flow to the crowd cylinder,
lift cylinder and winch motor is stopped. A horn is activated to
give a warning to the operator in all cases. To move the hook
block away from the boom head, the operator must retract
the boom raise the boom or lower the winch.
GROVE
Circuit Description
See the wiring diagrams in Schematics/Wiring Diagrams.
Power is made available through a 20 amp fuse to the circuit
relay under the console in the cab and to the limit switch on
the boom head. When the hook block reaches the upper
limit, the limit switch closes, energizing the relay. The
energized relay activates the three anti-double blocking
solenoid valves in the lift, crowd and winch circuits.
Electric Swivel
An electrical swivel is installed at the center of the mast
rotation. The swivel gives electric current continuity through
full rotation of the mast.
Published 10-21-2010, Control# 198-04
ELECTRIC SYSTEM
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