HW Group Poseidon 2250, Краткое руководство

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Poseidon 2250 – Short Manual HW group
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Port 2 - RJ45 - Industrial Bus (RS-485)
The RS-485 bus can be used to connect up to 31 sensors over up to
1000m, even in industrial environments. For convenience and ease of
use, TP cables and RJ45 modular jacks are used to wire the RS485
industrial bus.
The
RS-485 bus uses the blue pair of wires (pins 4 and 5), labeled A
and B. The brown pair (pins 7, 8) is used to supply 12V to power the
sensors .
If you use the S-Hub unit and the B-Cable module, the
green pair of
wires (pins 3, 6) is used for the return RS-485 connection . The green
pair of wires is not connected at the Poseidon 1250 unit.
Maximum wiring length: Up to 1000m in total
Supported sensors: Temperature, humidity, current, voltage, and more (see the overview
of available sensors)
Number of sensors on the RS-485 bus: Up to 31 physical
sensors
Power: 12V/120 mA, available at the RJ45 jack. Power supplied
by the bus is sufficient for up to 3 external sensors, an S-Hub can
be added to power more sensors
Communication cable: UTP, in some cases 4-wire phone cable
Alarm settings: Checking the reading against its Safe Range,
configuration in Poseidon Flash setup
Polling period: 800 ms to 10 s (depending on the number of sensors, 10 seconds for 41
sensors)
Sensor address assignment: Manual, each sensor must have a unique address (see
sensor manual)
Range of sensor IDs: Sensors use IDs from 48 to 122, the address corresponds to the
ASCII code of 0..9, A..Z, a..z characters.
Disconnected sensor detection: Yes, disconnected sensors read as “-999.9”
Alarm if sensor is disconnected: If the sensor is set to alarm whenever its reading is
outside of the safe range, disconnection triggers the alarm
General RS-485 characteristics
Maximum wiring length 1000 m
Up to 32 devices on the bus (Poseidon unit + 31 sensors)
High resistance to noise in industrial environments
Daisy chain topology is necessary (as opposed to star topology)
Each device must have a unique address
Wire polarity must be respected
Line must be terminated at the beginning and at the end
Port 1 – RJ45
1 -
Not used
2 -
Not used
3 -
485 B return
4
B (-)
RS-485
Industrial bus
5 A (+)
6
485 A return
7 GND
Ground
8 +12V
Power