Ahlborn ALMEMO 2390-5, Руководство по эксплуатации

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Volume flow measurement
For all flow sensors not only the functions for averaging are provided but also
functions for entering the cross-section and diameter of ventilating channels
and for calculating the volume flow. The average flow velocity can be deter-
mined roughly by scanning the whole cross-section or exactly by means of net-
work measurements according to DIN. For dynamic pressure probes both tem-
perature compensation and atmospheric pressure compensation are provided.
Under the appropriate environmental conditions these values can be either
entered manually or measured automatically.
PROCESS FLOW PROGRAMMING
To record the measured values from all connected sensors in digital form a cy-
clic measuring point scan with a time-based process flow control is required.
This feature involves the real-time clock, the print cycle, and, if high-speed
processing is required, the conversion rate itself. The measuring operation can
be started and stopped via the keypad, the interface, an external trigger signal,
or by exceeding a specified limit value.
Date and time-of-day
Each measuring operation can be logged either using the real-time clock with
the date and time-of-day function or purely in terms of the actual measuring ti-
me.
Print cycle
The print cycle can be programmed to any value between 00:00:01 (1 second)
and 59:59:59 hh:mm:ss. This function permits cyclic saving and output of mea-
sured values to the interfaces and cyclic calculation of the average and sum of
values.
Print cycle factor
The print cycle factor can be used to limit data output from particular channels;
this may prove necessary in order to reduce excessive data flow.
Averaging over measuring point scans
The measured values obtained by scanning measuring points can be averaged
either over a number of measuring points or over one particular measuring
point either for the total measuring time or over the print cycle time. Function
channels are provided for the cyclic output of such average values.
Conversion rate
With ALMEMO
®
devices all measuring points can be continuously scanned with
a conversion rate of either 2.5 or 10 measuring operations per second. It is al-
so possible to output all measured values to the interface.
Measured value memory (option S)
Measured values can be saved manually, cyclically, or at the selected conversi-
on rate to an internal 32-KB EEPROM (with sufficient capacity for up to 6000
measured values). Each measuring operation can also be started and stopped
ALMEMO
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2390-5 7
Functions