Ahlborn ALMEMO 8590-9, Руководство по эксплуатации

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4. Introduction
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Scaling
The corrected measured value on each measuring channel can also be further
scaled in terms of zero-point and gain - using the base value and factor. The
decimal point position can be set by means of the exponent function. The scaling
values can be calculated automatically by setting to zero and entering the nom-
inal value.
Limit values and alarm
Per measuring channel two limit values can be set (1 maximum and 1 minimum).
In the event of one of these limit values being exceeded relay output modules
actuate the associated alarm contacts; these can be allocated individually to
specific limit values. Hysteresis is set by default to 10 digits but this can be ad-
justed to any number between 0 and 99. The exceeding of a limit value can also
be used to start or stop measured value recording automatically.
Sensor locking
All sensor data stored in the connector EEPROM can be protected by means of
a graduated locking function against undesired access.
4.1.2 Measuring operations
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, and sen-
sors with function channels. All activated measuring points are continuously
scanned at a rate of 10 mops (measuring operations per second).
If there are a lot of measuring points involved the response time can be short-
ened by increasing the measuring rate accordingly. If the selected measuring
point (M0) needs to be smoothed or output at an analog output, it can be as-
signed preferred status; it will then be rescanned with each 2nd cycle (semi-
continuous mode).
Measured values
Measured values are acquired automatically with auto-zero and self-calibration;
however, they can also be corrected and scaled arbitrarily as required. With
most sensors a sensor breakage is detected automatically.
Analog output and scaling
Each measuring point can be scaled, by means of analog start and analog end,
in such a way that the measuring range thus defined covers the full range of the
analog output (2 V, 10 V, or 20 mA). At the analog output the device can output
the measured value from any measuring point or a programmed value.
Measuring functions
With some sensors, to achieve optimal measured value acquisition, certain spe-
cial measuring functions are required. Cold junction compensation is provided
for thermocouples; temperature compensation is provided for dynamic pres-
sure, pH, and conductivity probes; and atmospheric pressure compensation is
provided for humidity sensors, dynamic pressure sensors, and O
2
sensors. On
infrared sensors the parameters for zero-point correction and gain correction