Wireless Temperature, Humidity, Air Pressure and Motion Sensor

Check out this Victron Energy tech talk where they discuss this.

RuuviTag is a wireless Bluetooth sensor node that measures temperature, humidity, air pressure and movement*. You can read live measurements and history data directly on your smartphone using Ruuvi’s mobile app for Android and iOS, or pair it with your Bluetooth capable Victron GX device such as the Cerbo GX to monitor and even control relays (requires Venus OS v2.80).

(* Air Pressure and Movement is not currently supported by Victron GX Devices)

Temperature

RuuviTag works in both cold and hot environments. This makes it possible to measure temperature in demanding locations.

RuuviTag work in a range: -20°C to +70°C with the standard battery, or -40°C to +85°C with a special battery – not included)

Humidity

With RuuviTag, you can respond to air humidity changes in real-time. Protect your valuable items such as musical instruments, plants or constructions.

Range: 0-95%

Pressure

RuuviTag’s air pressure sensor can be used to forecast sudden weather changes, such as upcoming storms. It can also be used to analyse altitude changes from the sea level to high mountains.

Range: 300-1100hPa

Movement

RuuviTag knows exactly when it’s moved. Known when the postman opened your mailbox outside and get notified if someone visited your hotel room while you were gone.

Features:

Only the best parts
RuuviTag looks sleek and clean, but it can still operate in challenging environments. It’s designed with passion by the very best engineers.
Multi-Year Battery
User-replaceable CR2477 lithium battery. Lifetime 2-3 years.
History Logs
Up to 10 days of downloadable environmental history data. Logged every 5 minutes.
Long Range
Bluetooth beacon technology offers a better range compared to traditional Bluetooth devices.
No Pairing
Because no connection is needed, your phone can simultaneously listen to numerous sensors.
Wide Temperature
Wide -40°C to +85°C temperature range with the special Ruuvi battery. (Default -20°C to +70°C.)
Weather Resistant
Tolerates cold, hot and wet conditions.
Open Source
Firmware, electronics and mobile apps are all open source.

Ruuvi and Victron GX Device

Picture showing the sensor, and the reported data on Touch Display:

Here is how the data looks on the VRM Portal:

Controlling a relay on temperature

The relays on the GX device can now be controlled by temperature.
For example to switch a fan or heating pad. Here are two screenshots showing the configuration:

In the above example, the second relay will switch when the temperature in the engine bay rises above 45 degrees, starting the fan and it will switch the fan off once the temperature drops below 40 degrees C.