Broderson IC-400-3B Operation And Maintenance Manual Download

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SAFETY DEVICES

There are certain safety devices on the IC-400 that are designed to maintain control of a

load even if power or hydraulic line failure occurs. The operator should understand the

function and operation of these devices so that a continual check on their performance can

be made. There are other safety devices on the IC-400 designed to assist in the safe

operation of the crane. These devices work with the control system, hydraulic system or

engine to avert potential hazards. The operator should also understand how these devices

work and how to routinely check if the device is functioning properly.

OUTRIGGER CYLINDER CHECK VALVES:

A double-acting check valve is mounted on 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 mounted into the cylinder barrel. This valve holds the boom

in the elevated position if 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, 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 mounted to the telescoping cylinder. This valve holds the

cylinder in the extended position if power or hydraulic pressure line failure occurs. This

valve is adjustable to hold the desired load. If the boom creeps in under load, the 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.

HOIST BRAKE AND HOLDING VALVE:

The hoist has an automatic brake in the gearbox and a holding valve mounted directly on

the hoist motor to hold the load. A clutch in the gearbox allows the winch to turn freely in

the RAISE direction. The brake is pilot released in the LOWER direction and should allow

smooth stops of a load on the hoist.

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 the control system, to stop the

hydraulic circuit. This system will block the HOIST RAISE, TELESCOPE EXTEND and

BOOM LOWER. No other circuits are affected. These circuits are returned to normal

operation by operating the HOIST LOWER or TELESCOPE RETRACT control. An

emergency over-ride is provided so the boom can be operated in case of system failure.

This button is located on the RCL Display. When the over-ride is selected, a countdown

timer is displayed, indicating how long the over-ride will be active.

W A R N I N G

We recommend the emergency override button be used with discretion. Improper or careless
use of this operation can cause damage to the crane and endanger people and property. The
operator who uses this button in an emergency should use good judgment.