Theodor Friedrichs COMBILOG 1020, Hardware Manual

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Hardware Manual COMBILOG 1020
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8
MASTER FUNCTION
8.1 Master function
The two interfaces and the master function of the COMBILOG
1020 allows a configuration of a complex measurement system.
In such a system with activated master function the datalogger as
master is able to read out the other bus users (slaves)
This feature is used to extend the number of inputs and outputs
of the COMBILOG 1020 in case the 8 analog inputs and 6 digital
inputs/outputs of the datalogger are not sufficient. Other
COMBILOG’s 1020 can be connected to the RS-485 interface as
slaves. The master datalogger reads out the measured values
(actual instantaneous values only!) of the slave modules auto-
matically via the bus and stores them in its memory . By this
method complex systems to record up to 92 channels can be re-
alised easily.
The advantage of this master function is a flexible distribution of a
number of inputs and outputs and the sensors can be located in
an area over some kilometres. The data storage is central in the
master datalogger either in the internal buffered RAM or on a
PCMCIA card.
These data can be read out directly via the RS232 interface or via
telephone or GSM modem.
Arrangement of such a measurement system with COMBILOG
1020 and slave moduls is described by following steps: