Alta Humidity Sensors with firmware 14.x and later support calibration saved to the sensor’s memory. All Generation 1 Humidity Sensors and Alta Humidity Sensors with firmware version 14.x and prior do not support calibration saved to the sensor. Any calibrations applied to these earlier sensors only support an Offset as applied to the software. Actions are triggered based on the value reported by the sensor at the sensor level (and not the value as displayed in the iMonnit Portal the applies the offset). Therefore you may see the reading displayed accurately from the user’s perspective in the iMonnit Online Portal, but find the Action is being triggered by a value that does not include the applied offset.
In order to trigger Actions based on the Calibrated/Offset value entered using the Calibrate feature, you will need a newer Alta sensor running firmware version 14.x or later. Older sensors will not trigger Actions based on the Calibrated/Offset value.
When this comes into question
If you receive a notification from a Humidity sensor that you suspect may not be triggered from the applied Calibration/Offset:
- Check the version of the sensor:
- Log into the iMonnit Online Portal.
- Select Networks in the main menu.
- Select the network that has the Humidity sensor you are reviewing.
- Find the sensor listed; look for RadioBand to include “Alta”. Look for the firmware version; the below example is a sensor running firmware version 10.22.10.5.
If you do not see the word “Alta”, you have a Generation 1 sensor, and your sensor will not trigger Actions based on the Calibrated/Offset value.
If the firmware is 14.x.x.x or earlier, your sensor will not trigger Actions based on the Calibrated/Offset value.
If your sensor is a previous version, you can review the data that actually triggered the Action.
2. Export the sensor Readings, and review the raw data.
- Log into the iMonnit Online Portal.
- Select Sensors.
- Select the appropriate Network.
- Select the sensor.
- Select the Readings tab.
- Set the date for the desired time period.
- Select the cloud-download icon to export the data to CSV.
- Look for the “Raw Data” column of the CSV file for the reading delivered directly from the sensor. If there is a software Offset applied, you will find a different value in the Raw Data column verses the Value/Formatted Value columns. The Raw data will contain the reading reported at the sensor level. The Value/Formatted Value column will contain the Calibrated/Offset value applied through the portal.
Differences in the iMonnit Portal in the sensors’ Calibrate tab
In newer Alta sensors with firmware version 14.x and later, the Calibrate tab will display a Humidity and Temperature Offset rather than entering the Actual Reading. In these fields, you would enter the difference between the reading of the Monnit sensor and your reference, save, and the offset will be applied upon the sensor’s subsequent check in. For example, if your sensor reading was 20°C, and your reference read 18°C, you would enter “-2”, and click Save. The subsequent check in of the sensor would accept the -2°C offset.
In earlier Gen1 and Alta sensors with firmware prior to 14.x, the Calibrate tab will display fields to enter the Actual Reading values. In these fields, you would enter the value of your reference, save, and the calibration will be applied to the sensor on its subsequent check in.
After entering calibration
In newer sensors, the calibration is accepted on the sensor’s subsequent check in (just as most Monnit sensors operate). However with the older sensors, the Calibration/Offset is applied immediately to the software. Therefore you can review the readings as shown in the Readings tab of the sensor, and the offset will immediately affect the readings (including the history).
Improvements in the Monnit hardware and firmware allowed Monnit to include the ability to apply offsets to current Humidity sensors. Although this is not backwards compatible, the ability to support this on older sensors is made possible by improvements in our software. This comes with important caveats which were outlined in this article, but you should be able to successfully operate with Calibration/Offsets with the information provided on how it works. Feel free to contact firstname.lastname@example.org with further inquiries.