LSI-Robway RCI-1550 LM, Инструкция по эксплуатации

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7.11. Boom Stop Friction (compression) correction
7.11.1.
Introduction
Some cranes attempt to limit the high angle of the boom by employing a physical boom Back-Stop.
When this Back-Stop takes the form of a spring, acting so as to oppose the raising of the boom, it
can affect the load reading on LOAD MOMENT systems.
This is because Load Moment systems measure the force being applied on the boom by the load.
If there is some pre-loading of the boom by the boom Back-Stop then it is measured as force being
applied by the load and the system will thus see a bigger load on the hook than there actually is.
To avoid the boom Back-Stop force altering the load reading, three Function Codes are employed.
These Function Codes are described below.
7.11.2.
Boom Backstop Function Codes
7.11.2.1. Backstop Low Angle
This is
the physical boom angle at which the boom backstop first begins applying force
to
inhibit the boom luffing any higher. It should be close to the angle at which the boom first
makes contact with the backstops as it is luffed up.
7.11.2.2. Backstop High Angle
This is
the physical boom angle at which the boom is restricted from moving any higher (by
the boom back-stop).
For most cranes this value should be known, however, it can be
measured simply by luffing the boom to the highest possible angle and measuring the
angle.
7.11.2.3. Backstop Load Error
This value represents
the error in the load reading when the load is luffed from the "Low
Angle" to the "High Angle."
If a known 5t test weight was luffed up to the "High Angle, "
and the display then showed 8t, then the "Backstop Load Error" would be (8t - 5t) = 3t.
7.11.3.
How to Calibrate
To measure the
Backstop Load Error
it is first necessary to ensure that the current value for this
parameter is 0. This requires selecting the appropriate Function Code, and entering 0 into the
display. The display must be fully calibrated in regard to all other facets aside from the
Backstop
Load Error
. A known test weight is lifted (with the boom angle below the
Backstop Low Angle
) and
the weight should be verified against the calibrated display reading. The boom is then luffed up to
the
Backstop High Angle
and the erroneous load reading recorded. The value for the
Backstop
Load Error
is equal to the load reading at the max. angle minus the actual weight of the load. This
value should be entered against the appropriate Function Code for setting the
Backstop Load
Error.