Some Monnit wireless sensors can be calibrated to provide more accurate readings (ex. temperature sensors). This tech tip will demonstrate the process of calibrating a Monnit wireless sensor.
Before you can calibrate your Monnit wireless sensor, it is important to note that you will need to have an accurate source for comparison to the Monnit wireless sensor.
If calibration is possible for a sensor, the "Calibrate" tab will be visible in the detail view. Click the tab to open the sensor calibration settings window.
To calibrate a sensor, you will want to ensure that the environment of the sensor and other calibration device is stable. Note the "Expected Next Check-in" time for the sensor you are calibrating and take a reading from your calibration device a few minutes prior to the sensors next check-in. Enter the actual (accurate) reading from the calibration device into the text field, then click "Calibrate". To ensure that the calibration command is received prior to the sensors next check-in, press the control button on the back of the gateway, once, to force communication (Cellular and Ethernet gateways). If using a USB gateway, open the gateway application on the PC and click the "Send Messages to Server" button.
After pressing the "Calibrate" button and pressing the gateway button, the server will send the command to calibrate the specified sensor to the gateway. When the sensor checks-in, it will send the pre-calibration reading to the gateway, then receive the calibration command and update it's configuration. When the process is completed, it will send a "Calibration Successful" message. The server will display the sensor's last pre-calibrated reading for this check-in, then all future readings from the sensor will be based on the new calibration setting.
It is important to note that after calibrating the sensor, the sensor reading returned to the server is based on pre-calibration settings. The new calibration settings will take affect on the next sensor heartbeat.
Note: If you would like to send the changes to the sensor right away, please remove the battery(s) for a full 60 seconds, then re-insert the battery(s). This forces the communication from the sensor to the gateway and this the message to make a change from the gateway back to the sensor. (If the sensors are industrial sensors, turn the sensor off for a full minute, rather than removing the battery).
For more information on using Monnit wireless sensors, visit the support section of our website.