Ammonit METEO-32, Руководство пользователя

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Sensors
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Ammonit GmbH / 2005 - 2009 21
2.11. Internal measurements
In the Data Logger, 4 measurements are made in addition to the activated input
channels, so as to be able to check internal system parameters continually, and
if necessary to warn against overheating or the loss of a power supply (see
"Warnings"). These internal results can also be activated as normal
measurement channels and registered.
Internal measurements Meas. range Resolution
External supply 0 ... 26 V 0.1 V
Battery, left 0 ... 10 V 0.1 V
Battery, right 0 ... 10 V 0.1 V
Internal temperature -40°C ... + 80°C 1°C
Note: the internal temperature is recorded with an offset of +40°C, so it is always
necessary to subtract 40 from the value before any evaluation.
2.12. External signal converters
Ammonit Data Loggers have an internal signal converter to receive signals in
usual forms, such as frequencies, or analog voltages. However, adapted input
modules may be needed for special tasks; for example, high-resolution
temperature measurements require PT100 elements with 4-cable technology,
and when determining electric power it is better to work with signal transformers
which directly multiply voltage and current. For such applications, adapters with
an RS485 interface are available (see Gantner….) which are connected to the
Data Logger by a simple two-wire cable and controlled by means of the
standard MODBUS-protocol.
In order to receive data through such interfaces, the Data Logger has eight
additional channels (Cascade 1 .. 8), which can be activated in the usual way in
the "Channels“ window. The parameters of the attached Modbus module
(address and register) are defined under "Cascade Settings“. The data can be
stored in the format provided by the module. Note that values must lie in the
range 0 to + 65 535, and that negative values are not permissible.