JLG 1250AJP Operator Manual - Manual (Page 60)

SECTION 4 - MACHINE OPERATION
4-6 – JLG Lift – 3121170
Controlled Angle
The Controlled Boom Angle System minimizes the interaction of
swing and drive functions with the envelope edges. This interac-
tion is due to two factors. First, the envelope is controlled relative
to gravity regardless of ground slope and second, the turntable/
boom mounting is effected by swing and drive functions when
the ground slope varies. This can cause the boom position to vary
within the envelope or even violate the envelope edges when
swinging or driving without intentionally moving the boom. The
controlled boom angle system automatically activates either the
tower or main boom lift up or down during swing and drive com-
mands to maintain a constant boom angle relative to gravity.
Controlled boom angle is disabled with any envelope violation or
failure.
Swing Speed Proportioning
The boom control system sensors sense the distance the platform
is extended from the centerline of rotation, allowing higher
swing speeds with the platform nearest to the centerline of rota-
tion and gradually slower swing speeds the further the platform
gets from the centerline of rotation.
Stability
Machine stability is based on two (2) conditions which are called
FORWARD and BACKWARD stability. The machine’s position of
least FORWARD stability is shown in (See Figure 4-2.), and its posi-
tion of least BACKWARD stability is shown in (See Figure 4-4.)
TO AVOID FORWARD OR BACKWARD TIPPING, DO NOT OVERLOAD MACHINE OR OPER-
ATE THE MACHINE ON AN OUT-OF-LEVEL SURFACE.