Oshkosh JLG 1500SJ, Руководство по обслуживанию и ремонту

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SECTION 4 - BOOM & PLATFORM
4-4 – JLG Lift – 3121262
Drive/Steer – Boom Function Interlock System (CE
ONLY)
The Drive/Steer – Boom Function Interlock System uses the
Transport Position Sensing System to sense when the boom is
out of the transport position. All controls are simultaneously
functional when the booms are within the transport position
as on the standard machine. When the boom is beyond the
transport position, the control functions are interlocked to
prevent simultaneous operation of any boom function with
drive/steer. The first function set to be operated in this mode,
becomes the master function set. In other words, while oper-
ating drive/steer functions the boom functions are inoperable.
Likewise, while operating boom functions drive/steer func-
tions are inoperable.
Jib Stow System
The stowed length of the machine can be reduced to enable
transport on standard trailers by swinging the jib to the right
using the jib stow rotator. The control system will prevent
swinging the jib unless the axles are retracted, the boom and
jib are in the transport position (refer to Transport Position
Sensing System), and the jib stow override button on the plat-
form control panel is held in combination with the jib stow
function switch. When the jib is stowed, automatic platform
leveling is disabled, the boom is restricted to the transport
position, and axle extension is disabled. This system is func-
tional only in the 500 lb (227 kg ANSI markets or 230 kg CE
market) mode of the Dual Capacity System. Jib telescope func-
tion will resume when the jib is fully stowed along side the
main boom.
Envelope Tracking System
The Envelope Tracking System uses the envelope control sen-
sors to enhance the control of the boom within the working
envelope. Due to the shape of the working envelope, the max-
imum boom angle varies with telescope length. To maintain
unrestricted operation of the boom, the lift down function is
automatically introduced while telescoping in only when the
boom is on the rearward edge of the envelope. This only
occurs when telescoping in along the rearward edge and is
not used elsewhere within the envelope or when telescoping
out. Envelope tracking is disabled with any envelope or
moment violations or failures. The envelope tracking function-
ality and be turned off using the manual position of the boom
control select switch. Refer to Boom Control Select.
Moment Control System
The Moment Control System is the secondary means of con-
trolling the stability of the machine. This system uses a load
moment pin to attach the lift cylinder of the boom to the turn-
table. This pin is instrumented with gauges allowing the forces
in the pin to be monitored. These forces are used to compare
the actual boom moment (force at a distance) to a predeter-
mined allowable boom moment. In controlling the boom
moment, the position and load of the boom is controlled. The
moment control system will detect moments larger than
expected as well as those smaller than expected. This effec-
tively controls the forward and rearward positions of the
boom. The moment control system varies the maximum
allowable moment based on ground slope. On level ground
and with rated load in the platform, the allowable moments
establish a working envelope slightly larger than the Envelope
Control System’s envelope to minimize interaction of the sys-
tems. With increasing ground slopes and rated load in the
platform, the allowable moments may establish a working
envelope smaller than the Envelope Control System’s enve-
lope and may result in moment violations at the extreme plat-
form positions. Violations of the moment control systems
allowable moment will result in reduced function speeds, BCS
warning light illumination, restriction of functions, and sound-
ing of the platform alarm and the flashing of the BCS light with
attempts to operate restricted functions. The restricted func-
tions due to moment system violations related to forward
reach are disallowing jib functions, lift down, telescope out,
swing, drive, and steer. The restricted functions due to
moment system violations related to backward reach are disal-
lowing jib functions, lift up, telescope in, swing, drive, and
steer. Recognized failures within this system will result in con-
trol by the Envelope Control System, reduced function speeds,
BCS warning light illumination. The boom will be restricted
from leaving the transport position until the failure is resolved.