| Industrial bus (RS-485)
Over RS-485 up to 31 sensors can be connected over distance up to 1000 meters in industrial applications. We use TP cables and RJ45 connectors for RS-485 line, it is very easy to use them for a common user.
The RS-485 bus consists of blue communication cable pair (pins 4,5), marked as A and B. Power supply 12V for sensors is conducted through the brown cable pair (7,8).
If you use delivered S-Hub unit or B-Cable module, the green cable pair (pins 3,6) is used to RS-485 bus return from the sensor to the hub unit.
# Maximum wiring length: 1000 meters of total length
# Supported sensors: Temperature, humidity, current, voltage and other sensor (>> The list of sensors)
# Number of sensor on RS-485 bus: Up to 31 sensors (see the device model)
# Power supply: 12V/120 mA on RJ45 connector
# Power consumption: Power supply from the Poseidon unit is sufficient for up to 3 sensors. Larger number of sensors must be supplied from external source, for example S-Hub unit
# Communication cable: UTP twisted pair, eventually 4-wirephone cable
# Alarm setting : Controlling of value in safe range, configurable via Poseidon Flash setup
# Sampling period: 800 ms to 10 seconds (according to the number of connected sensors, 10 seconds for 41 sensors)
# Sensor address: Manually, each sensor must have unique address (see the sensor manual)
# Sensor disconnecting detection: Yes, disconnected sensor responds "-999.9" value
# Sensor disconnecting alarm: Disconnecting of sensor causes Alarm status if sensor indicates alarm (value out of SafeRange)
Basic characteristics of RS-485
* RS485 line Daisy chain topology to connect up to 32 devices including Poseidon unitTotal wiring length up to 1000 meters
* Up to 32 devices on one line (Poseidon + 31 sensors)
* High immunity against industry disturbance
* Connecting in Daisy chain, not in star topography.
* Each device must have its unique address
* Polarity of conductors must be respected
* The end and the beginning of wiring must be terminated |
