The hydraulic power unit uses a 24 Volt, one horsepower DC motor to drive the hydraulic pump. The DC motor is powered by four 6 Volt DC, 245
Two control panels (Figure
Figure 2-2. Boom Lift Control Panel (Ground)
The ground and platform control panels include CHOKE and START buttons for use with boom models equipped with an optional DC/gasoline hybrid generator for continuous duty. Battery condition indicators show the charge state of the batteries. When pressed, a STOP button at each control panel immediately stops all boom motions. The ground control panel includes a lighted text window that displays the present operating status or an existing error condition. The platform control panel includes a horn button that sounds an audible alarm when pressed.
Boom elevation, extension and rotation speeds are selected from low to high by SPEED buttons. The lift and extension cylinders have
Only one boom motion is permitted at a time and only as long as the boom is within the safe operating zone (Figure
Figure 2-3. Range of Motion
Outrigger load sensing switches and level sensing interlocks prevent all platform boom operations until the four outriggers are properly extended, the trailer is level and the full weight of the boom lift is loaded onto the outriggers. A
Safety devices prevent the boom from retracting suddenly in the event of a hydraulic hose or system failure. It is strongly recommended that no one adjust or tamper with these safety devices. If service is required, please notify
Each cylinder rod is fully immersed in oil to prevent rust or corrosion of the cylinders during storage. It is important that the cylinder rods be kept clean and undamaged for the protection of the cylinder head packings.
In the event of power loss, control system failure or other malfunction, all boom movement functions may be accomplished by manual operations.
Manual lowering of the platform is performed by actuating valve plungers found on the base of each boom lift cylinder. Pushing and holding each valve retracts the corresponding boom lift cylinder. The boom may need to be rotated to a clear area before lowering.
Manual boom retraction and turntable rotation are accessed inside the pump compartment. The hand pump and selected valves on the hydraulic pump unit are used for these functions.
10