Limit Values and Alarm
Two limit values (1 max and 1 min) can be set for each measuring channel. An
alarm value printout can be performed if a limit value is exceeded and, by
means of relay output modules, alarm contacts are provided that can be
individually allocated to limit values. As a standard, the hysteresis is set to 10
digits, however, it can also be adjusted. Furthermore, limit value exceeding can
also be used to start or stop a measurement.
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.
MEASUREMENT
A total of up to 36 measuring 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 selected measuring point can be scanned
with a conversion rate of 2.5 or 10 measurements/second. The measured
value is calculated and provided on the analogue output, if it is available.
Measured Value
A continuous presentation of measuring data from the selected measuring
point is provided and also includes automatic zero point correction and optional
correction of the measured value or new scaling. Sensor breakage recognition,
exception: current measurements.
Analogue Output and Scaling
By means of analogue start and analogue end the indicated measured value
can be scaled so that the resulting measuring range covers the full analogue
output range (2V, 10V or 20mA).
Measuring Functions
Special measuring functions are required for some sensors in order to achieve
an optimal acquisition of measuring data. A cold junction compensation is
performed at thermocouples. A temperature compensation is performed at
dynamic pressure and pH and conductivity probes and an atmospheric air
pressure compensation is performed at humidity sensors and O
2
sensors. With
infrared sensors the parameters zero point and slope correction are used for
background temperature and emissivity factor.
Maximum and Minimum Value
Each measurement involves an acquisition and storing of the maximum and
minimum value. These values can be displayed, printed or cleared.
Functions
ALMEMO
8990-8
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