MTZ 1220.1, Operator'S Manual

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MTZ 1220.1/1220.3 Section G. Operating instruction
G1
Section G.
OPERATING INSTRUCTION
Hydraulic lift linkage
Hydraulic system of rear thee-point hitch
control is equipped with distributor-
regulator build in monoblock (HLL with
hydraulic lift) that provide system opera-
tion in the following modes:
• draft control;
• position control;
• mixed control.
Effective use of this mode depends on im-
plements coupled and on agricultural con-
ditions.
Position control
The position provides accurate and sensitive
control of the attached implement position
above the ground, such as spraying machine,
land leveler, etc. The position control can be
used with tillage machines. Semi-mounted
ploughs with remote cylinders etc.
But it is not recommended to use this type
of control on on fields with uneven surfaces.
Position control on the field with uneven
surface can lead to constant impacts that
arise due to quickly vertical displacement
of implement mounted.
Draft control
Draft control is the most appropriate mode
for use with mounted or semi-mounted
implements, the working bodies of which are
buried in the soil. The system is sensitive to
changes in tractive force (due to changes in
the soil resistance or the tillage depth)
through the central rod of the linkage
mechanism. The hydraulic system responds
to such changes by raising or lowering the
implement to support the given tractive force
at a constant level. The system reacts to the
force of compression and extension in the
central rod, thus being a dual action system.