JLG 1350SJP Service Manual - Manual (Page 235)

SECTION 4 - BOOM & PLATFORM
3121142 – JLG Lift – 4-1
SECTION 4. BOOM & PLATFORM
4.1 BOOM SYSTEMS
Broken Cable Indicator System
The boom on this model is a 4 section proportionally driven
telescopic boom. The inner mid boom is driven directly by the
telescope cylinder. The outer mid and fly booms are each
driven by separate wire rope systems. Each rope system con-
tains redundant ropes that are capable of allowing the opera-
tor to unknowingly continue use of the machine with a single
rope failure. These kinds of failures with the extend ropes are
self revealing to the operator so proper action can be taken.
Failures within the fly extend ropes are self revealing as they
are exposed on the exterior of the boom where a broken rope
would be obvious. Failures within the outer mid ropes require
the addition of the Broken Cable Indicator System in order to
be self-revealing to the operator. This system uses a proximity
sensor to detect excessive movement of the sensed rope as
would be expected with a rope failure. A broken rope detec-
tion results in illuminating the Cable Break indicator on the
platform control panel. No restrictions are made to the func-
tionality of the control system. It is the responsibility of the
operator to take the appropriate action.
NOTE: For more detailed information concerning system adjust-
ment and operation, refer to Section 6 - JLG Control Sys-
tem.
Platform Control Enable System
The platform controls make use of a time dependent enable
circuit to limit the time availability of “live” or enabled controls.
When the footswitch is depressed, the controls are enabled
and the operator has 7 seconds to operate any control. The
controls will remain enabled as long as the operator continues
to use any function and will remain enabled 7 seconds after
the last function has been used. While the controls are “live”,
the enabled light will be illuminated in the platform display
panel. When the time limit has been reached, the enabled
light will turn off and the controls will be “dead” or disabled. To
continue use of the machine the controls must be re-enabled
to start the timer system over again. This is done by releasing
all functions, then releasing and re-depressing the footswitch.
NOTE: For more detailed information concerning system adjust-
ment and operation, refer to Section 6 - JLG Control Sys-
tem.
Transport Position Sensing System
The transport position sensing system uses the boom angle
sensors and the boom length sensor mounted in the pivot end
of the base boom in addition to the boom length switch
mounted on the platform end of the base boom to sense
when the boom is in the position associated with high speed
travel. Above transport angle is recognized when one angle
sensor reads more than 15° with respect to gravity and resets
to within transport position when both angle sensors read less
than 10° with respect to gravity. Transport length is recog-
nized when both the length switch and length sensor read less
than 1 ft extension for the 1350SJP (2 ft extension for the
1200SJP). During failures of either the length switch or length
sensor, the transport length will be determined by the remain-
ing sensor or switch. The position of the articulated jib is not
considered.
This system is used to control the following systems:
• Beyond Transport - Drive Speed Cutback System
• Drive/Steer – Boom Function Interlock System – CE Only
• Jib Stow System
• Axle Extension System
• Oscillating Axle System
NOTE: For more detailed information concerning system adjust-
ment and operation, refer to Section 6 - JLG Control Sys-
tem.
Beyond Transport - Drive Speed Cutback System
When boom is positioned beyond the Transport Position, the
drive motors are automatically restricted to their maximum
displacement position (slow speed).
NOTE: For more detailed information concerning system adjust-
ment and operation, refer to Section 6 - JLG Control Sys-
tem.