5. Introduction
point position can be set by the exponent. By setting to zero and entering the
nominal value the scaling values can be automatically calculated.
Limit Values and Alarm
Two limit values (1 max and 1 min) can be set for each meas. channel. If a
limit value is exceeded alarm contacts, that can be individually allocated to limit
values, are provided by means of relay output modules. As a standard, the
hysteresis is set to 10 digits; however, it can also be adjusted between 0 and
99 digits. Furthermore, limit value exceeding can also be used to start or stop a
data logging.
Sensor Locking
All sensor data stored in the EEPROM of the connector can be protected
against undesired access by means of a graded locking function.
5.1.2 Measurement
A total of up to 36 meas. channels are available for 9 transducers, i.e. it is also
possible to evaluate double sensors, individually scaled sensors, or sensors
with function channels. The meas. channels can be successively selected for-
wards or backwards via keypad. By default all measuring points are scanned
continuously at a measuring rate of 10 mops and the data thus obtained is
listed in the display. However, if you want to have the measured values for the
selected channel sent to an analog output, it may be an advantage to use
semi-continuous mode instead; the output value will then always be refreshed
at half the measuring rate set - irrespective of the number of measuring points
involved.
Measured Values
The measured values of 1 to 20 measuring points can be indicated on the dis-
play in different menus (that can also be configured) in three font sizes, as bar
graph or as line chart. They are automatically acquired with auto zero and self
calibration and can also be arbitrarily corrected and scaled as required. A sen-
sor breakage condition is, with most sensors, automatically detected.
Analog Output and Scaling
By means of analog start and analog end any measuring point can be scaled
so that the resulting measuring range covers the full range of the bar graph or
line chart or of an analog output (2V, 10V or 20mA). The measured value of
any measuring point as well as a programmed value can be output to the ana-
log output
Measuring Functions
Special measuring functions are required for some sensors to achieve an opti-
mal data acquisition. The cold junction compensation is available for thermo-
couples, a temperature compensation for dynamic pressure and pH and
conductivity probes, and an atmospheric air pressure compensation for humid-
ity sensors, dynamic pressure sensors and O2 sensors. With infrared sensors
the parameters zero point and slope correction are used for background tem-
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