FIEDLER H1, Руководство пользователя

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Hydro Logger H1 User manual
FIEDLER
electronics for ecology
49
separate channel and to activate
an SMS alert according to this
calculated value. It is usual that
the archiving of this auxiliary
channel is suppressed (see
below). Other methods in the
"Calculation functions" menu inc-
lude, for example, the sum or di-
fference of two channels.
Very often, measuring probes and
sensors are connected to the te-
lemetry station via the RS485 serial communication interface. With this method
of communication between the station and the sensor, it is necessary to set the
communication address of the sensor and the number of the internal measure-
ment channel for the desired physical quantity (see overview table on the
following page) in addition to the appropriate measurement method.
The measurement method "
Intelligent probe via RS485/HART " is set for probes
from BD Sensors s.r.o. equipped with RS485 interface.
The measurement method "
Intelligent probe via RS485/FINET " is set for
FIEDLER probes and sensors equipped with RS485 interface.
Some quantities, such as pressure or flow, have a rich list of units in which the
desired quantity can be measured, archived and displayed. Other quantities,
such as rainfall or battery voltage, offer only one set of units.
An important parameter for determining the resolution of each monitored va-
riable is the number of decimal places with which the measured variables are to
be archived in the selected units of measurement. A higher number of decimal
places is at the expense of the allowed range. An inappropriate choice of the
number of decimal places may cause the maximum range to be exceeded, re-
sulting in 'clipping' of out-of-range values
.
The maximum possible magnitude that the measurand can take is 65535 for in-
tegers and it decreases decade by decade as the number of decimal places incre-
ases. Bipolar quantities such as temperature or voltage have half this maximum
possible value. This "limitation" results from the 16 bit archiving of the mea-
sured instantaneous values.
The relationship between the number of decimal places and the allowable range
of the monitored variable can be seen in the following table.
Tab. 1Maximum range of archived values
Number of decimal places Resolution Range of unipolar quantity Range of
bipolar quantity
0 1 0 ... 65535 -32767 to 32767
1 0,1 0,0 .. 6553,5 -3276.7 to 3276.7
2 0,01 0,00 .. 655,35 -327.67 to 327.67
3 0,001 0,000 .. 65,535 -32,767 to 32,767
R S 4 8 5
U n i t s
N u m b e r o f
d e c i m a l p l a c e s
N a m e t a g