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RMS-300v2 has an on board temperature sensor and supports external temperature sensors!

On Board LM75 Sensor

The onboard LM75 Temperature sensor is used to monitor ambient temperature in the vicinity of the RMS-300v2 board.
If temperature monitoring is required that is some distance away from the RMS-300v2 board, then see the information on external 1-Wire temperature sensors below.

Below is a screen shot of the RMS-300v2 onboard temperature sensor setup page. Preliminary setup steps are done in this area like entering notes and choosing the temperature format.

The RMS-300v2 web interface has High and Low triggers that can be set to fire alerts or scripts when the temperature is either too high or too low. Use the relay scripts to turn on a cooling fan for example. The High Trigger is used when the temperature rises above the High Trigger value. The Normal Trigger is used when the temperature falls below the High Trigger value.

Below is the Low Trigger interface. The Low Trigger is used when the temperature falls below the Low Trigger value. The Normal Trigger is used when the temperature raises above the Low Trigger value.

Below is an example of reading the temperature on the command line. Note: the file tempf contains the board temperature in Fahrenheit. The file tempc contains the board temperature in Celsius.

Using external 1-Wire temperature sensors

The RMS-300v2 has a 1-Wire port that is used to attach external 1-Wire temperature sensors. The RMS-300v2 board supports Dallas Semiconductor ® DS18B20 1-Wire temperature sensors. Up to eight DS18B20 1-Wire temperature sensors can be monitored.

Note 1: The 1-Wire port can also be used to power 5V devices that require no more than 100ma. The 1-Wire port can be powered on or off by using the web interface on the RMS-300v2 board.

Below is a diagram of how to hook up a 1-Wire DS18B20 external temperature sensor to the RMS-300v2 board.

Note 2: On sensors that we have tested from various suppliers, the power wire is always red, the ground wire is always black, the data wire is usually yellow, but not always. Sometimes the data wire can be another color, such as blue or green.

Note 3: For information on how to use 1-Wire temperature sensors with long runs of cable, see the PDF document below.
https://remotemonitoringsystems.ca/Downloads/1-Wire-Guidelines.pdf

Enabling the 1-Wire Interface Port

To enable the 1-Wire interface port, click on the RMS-300v2 setup icon. Next, click on the device manager icon and then click on enable 1-Wire Interface.

When the 1-Wire Interface has been enabled, a 1-Wire Devices menu item will appear in the left navigation bar on the RMS-300v2 web interface. Here you can add and view 1-Wire temperature sensors.