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8008250/1F7Y/V4-0/2022-06 | SICK
O P E R A T I N G I N S T R U C T I O N S | GM901
Subject to change without notice
PRODUCT DESCRIPTION
3
3.5
Standard scope of delivery
The basic version of the GM901 comprises
●
Sender
●
Receiver
●
Control unit with connecting cable (2 m)
●
Sender-receiver connection cable (15 m)
3.5.1
Control unit
The control unit serves in the measuring system as user interface and prepares and
outputs the measured values and performs control and monitoring functions.
The control unit can be positioned close to the sender; it can also be located up to about
1000 meters from the sampling point, e.g., installed in the switch center or monitoring
center of the industrial plant.
Functions:
●
Output of measured values, computed data and operating states
●
Communication with the peripheral equipment
●
Output of error messages and other status signals
●
Access during service (diagnosis)
3.5.2
PROFIBUS interface (if installed)
PROFIBUS connects the process control level (e.g., central computer, host, control room) to
the measuring device. Measured values, status states and error messages are queried
cyclically via the PROFIBUS. The GM901 supports PROFIBUS-DP-V1 with transfer rates
from 9.6 to 187 kBit/s. A device master file (GSD) is available for the evaluation unit to
define the interface. This contains specifications on device manufacturer, identification
number, transfer rates available, etc. This GSD (Profile GSD) of the device can be easily
used during project planning for the PROFIBUS.
A unique 7 bit device address (1-127) serves to identify PROFIBUS participants and can be
entered when setting control unit parameters. Addresses 126 and 127 are reserved and
must not be used.
Measured values provided
Measured values provided by the GM901 are defined in the device master file (GSD) as
input channels for the process control level (AI). The following Table shows the measured
variables with the respective assigned units of measure:
NOTE:
A terminator (terminating resistor) must be plugged to the final device.
Measured variable
CO
CO
ppm
CO
mg/m
3
(s.c.)
CO
mg/m
3
(a.c.)
