Broderson IC-80-3L 4X2, Installation And Operating Manual

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SAFETY DEVICES
There are certain safety devices on the IC-80 that are designed to maintain control of a load
if power or hydraulic line failure should occur. The operator should understand the function
and operation of these devices so that a continual check on their performance can be
made.
OUTRIGGER CYLINDER CHECK VALVE:
A double-acting check valve is built into each of the outrigger cylinders. This valve holds
the outrigger in the extended position, should power or hydraulic line failure occur. This
valve has no adjustment. If an outrigger creeps up while supporting a load, there is an
internal leak in the valve, or in the outrigger cylinder piston seal. In either case,
maintenance is required.
BOOM ELEVATION CYLINDER HOLDING VALVE:
A single-acting holding valve is built into the cylinder barrel. This valve holds the boom in
the elevated position should power or hydraulic pressure line failure occur. This valve is
adjustable to hold the desired load. If the boom creeps down with loads up through
maximum capacity, this valve should be adjusted. If adjustment fails to correct the problem,
there is an internal leak in the holding valve or the hydraulic cylinder. Refer to the main-
tenance instructions.
BOOM TELESCOPE CYLINDER HOLDING VALVE:
A single-acting holding valve is flange-mounted to the cylinder rod end. This valve holds
the cylinder in the extended position should power or hydraulic pressure line failure occur.
This valve is adjustable to hold the desired load. If the boom creeps in under load, this
valve should be adjusted. If adjustment fails to correct the problem, there is an internal leak
in the holding valve or the hydraulic cylinder. Refer to the maintenance instructions.
ANTI-TWO-BLOCK SYSTEM:
This system prevents damage to the hoist rope and machine components from accidentally
pulling the load hook against the boom tip. A pivot arm-actuated electric switch is
connected through a cable reel mounted on the boom to a solenoid dump valve in the
hydraulic circuit. This valve will dump the HOIST RAISE, TELESCOPE EXTEND and
BOOM LOWER, SWING LEFT and SWING RIGHT circuits. No other circuits are affected.
These circuits are returned to normal operation by operating the HOIST LOWER or
TELESCOPE RETRACT control.
An emergency override switch is provided so the boom can be operated in case of system
failure. This key-operated switch is located under the left side of the instrument panel.
W A R N I N G
We recommend the emergency override switch be used with discretion. Improper or
careless use of this switch can cause damage to the crane and endanger people and
property. The operator who uses this key in an emergency should use good judg-
ment.
Courtesy of CraneMarket.com