Genie Z-30/20N Service Manual page 39

June 2011
REV A
The platform support subassembly utilizes two load
support arms that are opposed in a full
parallelogram link. This isolates platform loads into
a shear or vertical state, which translates into a
compressive load. A spring in the parallelogram
link supports this purely compressive load
regardless of where the load is placed in the
platform.
As weight is added to the platform, the spring will
compress until, when the platform is overloaded,
the lower arm contacts a limit switch and thereby
activating the overload signal. When adjusted
correctly, the platform overload system will
deactivate normal boom operation at platform
capacity.
Note: Perform this procedure with the machine on
a firm, level surface.
1 Turn the key switch to platform control. Start the
engine and level the platform.
2 Determine the maximum platform capacity.
Refer to the machine serial plate.
3 Remove all weight, tools and accessories from
the platform.
Note: Failure to remove all weight, tools and
accessories from the platform will result in an
inaccurate test.
4 Using a suitable lifting device, place a test
weight equal to that of the available capacity
one of the locations shown.
Refer to Illustration 1.
Result: The platform overload indicator lights
should be off at both the ground and platform
controls and the alarm should not sound.
Result: The platform overload indicator lights
are on and the alarm is sounding. Calibrate the
platform overload system. Refer to Repair
Procedure 2-3, How to Calibrate the Platform
Overload System (if equipped).
Part No. 139378 Z-30/20N • Z-30/20N RJ • Z-34/22 • Z-34/22N
Section 3 • Scheduled Maintenance Procedures
CHECKLIST C PROCEDURES
5 Carefully move the test weight to each
remaining location. Refer to Illustration 1.
Result: The platform overload indicator lights
should be off at both the ground and platform
controls and the alarm should not sound.
Result: The platform overload indicator lights
are on and the alarm is sounding. Calibrate the
platform overload system. Refer to Repair
Procedure 2-3, How to Calibrate the Platform
Overload System (if equipped).
Illustration 1
6 Using a suitable lifting device, place an
additional 10 lbs / 4.5 kg of weight onto the
platform.
Result: The alarm should sound.
The platform overload indicator lights should be
flashing at both the ground and platform
controls.
Result: The alarm does not sound and the
platform overload indicator lights are not
flashing. Calibrate the platform overload
system. Refer to Repair Procedure 2-3,
How to Calibrate the Platform Overload System
(if equipped).
Note: There may be a 2 second delay before the
overload indicator lights flash and the alarm
sounds.
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