STX Signal Transmitter Installation and Operation ... - Kistler-Morse

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
○ ○ ○ ○ ○ ○ ○ ○
○ ○ ○
Resetting Manual
Calibration Parameters
The third page of the Manual Cal Menu has a
reset function. Use this menu to reset the
calibration to the defaults, listed below:
• Cnts/mV — dependent on Gain value
(see Chapter 8, MVS-STX Service Menu).
Value is 699.05 for the default Gain of 2.
• 0mV cnts — 1,048,576
• H_SPAN_W — 9,999*
• L_SPAN_W — 0
• H_SPAN_C — 1,298,576
• L_SPAN_C — 1,048,576
• ZERO_WGT — 0
• ZERO_CNT — 1,048,576
• SCF_WGT — 9,999*
• SCF_CNT — 250,000
*Decimal point/dummy zeroes are consistent
with Form.
Note
Reset has no affect on analog scale
factor counts and analog zero counts.
Linear
This function corrects nonlinearities from a
vessel’s sensor output. Use of this function
may be required if you notice one of the
following after the system is correctly calibrated
(using Auto Calibration):
• The MVS gives accurate results when
the live load is close to 0 and close to
the full scale (maximum live load) value,
but is consistently inaccurate between
those values.
• The MVS gives accurate results over
some or most of the live load range, but
is consistently inaccurate in one area.
Chapter 7. MVS-STX Calibration Menu
The word ‘consistent’ refers not only to an
error occurring, but that the error is approximately
the same each time. This type of error
may be caused by a non-linear response of
the vessel’s structure to changes in load.
This type of error can also result from layering
of multiple types of material in the vessel,
with differing densities, in distinct,
consistently defined layers.
Note
Changing the linearization table
incorrectly can cause the MVS to
display incorrect weight. Do not
change the linearization table unless
one of the above problems has
been noted.
The MVS’s linearization algorithm uses a fivepoint
piece-wise linearization method with
linear interpolation between points. Figure 7-4
illustrates the linearization operation.
Table 7-1 is the default linearization table,
consisting of five raw digital count values as
inputs and five corrected digital count values
as outputs. The default for Linear is Off.
Additionally, the raw and corrected default
values are identical, so the default linearization
table has no effect, even if linearization
is On.
Raw Value Corrected Value
1048576 1048576
1112576 1112576
1176576 1176576
1240576 1240576
1304576 1304576
Table 7-1. Default Linearization Table
Consult with K-M to determine the values to
input for linearization.
Indicated
Weight
1R
1C
Linearized
Output
Non-Linear
Input
Counts
2C 2R 3C 3R 4C 4R 5R
5C
Figure 7-4. Linearization Curve
7-9
Linearizing Table
Raw Corrected
Input Output
1R
1C
2R
2C
3R
3C
4R
4C
5R
5C
Requirements of table values:
1R