Genie Z-45 XC, Руководство по обслуживанию

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Part No. 52709 Genie Z-45/25 & Genie Z-45/25J 3 - 1
Section 3 • Theory of Operation First Edition • Second Printing
Theory of Operation
Power Source
The Genie Z-45/25 and Genie Z-45/25J are
powered by either a gasoline/LPG engine or one of
two diesel engines. The gasoline/LPG option uses
a Ford LRG-425 EFI engine rated at 70
horsepower @ 2500 rpm. The diesel options
include a Deutz F3L 1011F engine rated at 36
horsepower @ 3000 rpm, and a Perkins 104-22
KR engine rated at 41 horsepower @ 2800 rpm.
Hydraulic System
All machine functions are performed by the
hydraulic system. The hydraulic system can be
divided into two groups: Boom/Steer functions and
Drive functions.
Boom/Steer functions are powered by a single-
section gear pump, rated at 7 gpm (26.5 L/min).
When the engine is running, this pump supplies
hydraulic fluid under pressure to the function
manifold, where the directional and flow control
valves are located. To protect from over-
pressurization of the Boom/Steer system, the
pump is provided with a pressure relief valve, set
at 3500 psi (241.3 bar).
Drive functions are powered by a bi-directional,
variable output piston pump rated at 0 to 30.3 gpm
(0 to 114.7 L/min) @ 2500 rpm. Two internal 3200
psi (220.6 bar) relief valves are used to prevent
over-pressurization of the closed loop drive
system.
The boom lift cylinder, boom extend cylinder,
platform leveling slave cylinder, platform rotator
and jib boom cylinder (Z-45/25J models)
incorporate counterbalance valves to prevent
movement in the event of a hydraulic line failure.
Electrical System
Boom/Steer functions are accomplished by
moving a toggle switch or a controller, which sends
voltage to the appropriate directional control valve.
These directional valves determine which direction
the hydraulic fluid will travel. The amount of
hydraulic fluid volume is determined by a
proportional valve or flow regulator valve. A
proportional valve receives a variable voltage
signal and delivers more hydraulic fluid as the
voltage increases. A flow regulator valve is a
mechanical valve and delivers a predetermined
amount of hydraulic fluid.
Drive forward or reverse is accomplished by
pressing down the foot switch in the platform and
moving the drive controller (joystick) in the
appropriate direction. When activated, the drive
controller completes a circuit to the electronic
displacement controller (EDC). The EDC regulates
drive pump displacement in direct relation to the
drive controller position. A horsepower limiter
printed circuit board (located in the platform control
box) is provided to maintain engine RPM as drive
system loads become greater. This is done by
sensing engine RPM (via an AC tap on the
alternator) and limiting the amount of current
supplied to the drive controller/EDC, which
destrokes the pump, reducing pump output.