Bwired Home Online home in the Netherlands
Poseidon 1250, Measurement of temperature sensors and controlling digital inputs over network.
For measuring temperature on Bwired I use the Poseidon 1250 from the HW-Group. The Poseidon is an Ethernet enabled device capable of monitoring temperature sensors and several digital inputs.
Sensors can be connected to the Poseidon model 1250 unit via two busses or you connect directly sensor's contacts. This device measures values of connected sensors, I can access the data over specialized protocols or simply via the web browser.

The Poseidon 1250 has the following input options:
- Industrial bus (RS485): up to 31 sensors, up to 1000m
- 3 Digital inputs: connect relay dry contact directly
- IT bus (1-Wire): up to 10 low cost probes, RJ11 wiring

Connection schematic Poseidon 1250 web controller
Poseidon 1250

The Poseidon 1250 supports up to 42 sensors (probes) for temperature, humidity, air-flow and other value monitoring. Each sensor monitors safe range and can notify when a value gets out of a safe range (Alarm status) via Email or SNMP trap sending.
- Temperature (up to 42 sensors up to 1000 meters, -55 °C to +640 °C)
- Humidity (up to 25 sensors up to 1000 meters)
- Binary input / contact (up to 3 smoke detectors, shake, movement, flooding, angle, close/open door, air-flow etc.)
- General input (0 to 10V, 4 to 20mA – using external converters to RS-485)


Poseidon 1250 complete overview
Poseidon 1250 complete overview 


Temperature sensors I use on Bwired
1-wire DS18B20 sensor 

On Bwired I have connect 10 of these DS18B20 1-Wire sensors in parallel to a single bus, each sensor is identified by a unique serial number. For measuring the temperature sensor uses an integrated element with accuracy of ± 0,5°C.

Basic properties:
- Different cable lengths and design types of measuring probe
- Temperature measuring in range from -55°C to +125°C
- Up to 10 sensors connected in parallel
- Each sensor contains a unique identifier
- Sensor can cooperate with SNMP thermometer Poseidon


Bwired Poseidon 1250 temperature overview
Bwired Poseidon 1250 temperature overview

Here you can see the Poseidon 1250 web server real-time in action: Bwired Poseidon Web server
It is also very simple the get all the current values by XML check this real-time XML link Bwired Poseidon XML view, very easy to store in a database.