Kistler-Morse KM STXPlus User Manual

Page 16

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CHAPTER 3: STAND-ALONE ANALOG CALIBRATION AND SET UP

the average. This results in fewer variations
in output. For example, fewer variations in
a display reading results in a display that is
easier to read. The averaging factor affects
the value seen on a dislay as well as current
otuputs and serial outputs.

The default is 5.

No more than 20 is advised.

DSP Filter
Vibrations in a vessel can cause changes in
the STXplus output, even though no material
is moved, because the vibrations affect the
vessel’s structural response. The Sentry™
DSP Filter reduces output changes that can
result from vibration.

The A/D converter digitizes the signal coming
from a sensor. The STXplus picks the first
signal as a reference median; this value is
used in calculating the output. As shown in
Figure 3-4, the STXplus then compares the
following signals to the reference median
when either of the following happen:
1. The number of successive signals above
or below the median exceeds a triggering
number.
2. A signal falls outside a user-defined
window around the reference median.

When the STXplus recalculates the reference
median, the transmitted data changes to
correspond to the new reference median.
The DSP Filter affects the STXplus current
output as well as the serial output.

The DSP, when in analog mode, will use a
default factor of 80% and a quality of 3.

DSP Enable
DSP Enable turns the DSP Filter on and off.
The default state is on.

DSP Step
DSP Step is a window, in percent, of span
above and below the reference median.

As shown in on the left side of Figure 3-4, if a
large signal change is detected that falls
outside of the window, the STXplus
immediately moves the location of the
reference median to that point. This allows
the STXplus to adjust quickly to rapid
material movement.

The default step is

0.5% of span.

Input Voltage Range
The type of sensors connected to the
STXplus determines the required setting.

An input range of ±75mV is used with
full-bridge sensors of 2mV/V or 3mV/V.

An input range of ±0.5V is used with
half-bridge load cells. Some high output
half-bridge applications may require ±1V
or ±2V.

The default range is ±0.5V for
Kistler-Morse

®

Microcell and Load Cell

sensors. An input range of ±0.5V is
appropriate for Kistler-Morse

®

Load Disc II,

LD360s, LD3, and Load Stand II sensors.
An input range of ±75mV is appropriate for
Kistler-Morse

®

LD3xi, LD3xiC, TC-1, or other

full-bridge sensors.

Amplifier Gain

Sensor Input Range

1

±2V

2

±1V

4

±0.5V

32

±75mV

Modbus Baud Rate
The setting determines the baud rate for
RS-485 port serial communication.

The

default is 115K baud rate.

Channel Enable
Enables/disables Channels 1-4.

The default

is Channel 1 only.

3-7

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