Ahlborn ALMEMO 2290-4 V5, Руководство по эксплуатации

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Scaling
The base value and the factor allow for a further scaling of the corrected
measured value of each measuring channel for zero point and slope (gain). The
decimal 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 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 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.
MEASUREMENT
A total of up to 4 measuring channels are available for each transducer, i.e. it is
also possible to evaluate double sensors, individually scaled sensors, or
sensors with function channels. The measuring channels can be successively
selected forwards or backwards via keyboard. The selected measuring point
can be scanned with a conversion rate of 2.5 or 10 measurements/second. The
measured value is calculated and indicated on the display or, if available,
provided on the analogue output.
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.
A sensor breakage condition is, with most sensors, automatically detected
(exception: connectors with shunts, dividers or additional electronics).
Measuring Functions
Special measuring functions are required for some sensors in order to achieve
an optimal acquisition of measuring data. The cold junction compensation is
available for thermocouples, a temperature compensation for dynamic pressure
and pH and conductivity probes, and an atmospheric air pressure
compensation for humidity sensors, dynamic pressure sensors and O
2
sensors.
With infrared sensors the parameters zero point and slope correction are used
for background temperature and emissivity factor.
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).
6 ALMEMO
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2290-4
Functions