Using a Monnit Sensor to Compare Accuracy

If you have a Monnit sensor, and you are concerned of the accuracy of the device, there is a method by which you can review the sensor’s accuracy. This is especially useful if you see a discrepancy between the reading from a refrigeration unit differ than that which you Monnit sensor reports. In order to do this, you will need to have access to multiple operating Monnit temperature sensors which can have their probes placed in the same area.

Factors that may lead to the impression that the readings from a Monnit sensor are inaccurate:

• Inaccurate calibration applied by a User in the portal.
• Probe placement (example: placing the probe in the front of a fridge/freezer instead of the back where a built-in probe may be located).
• Time of reading (example: comparing a Monnit sensor reading from a previous heartbeat to an instantaneous reading on a display).
• Defrost cycles.
• Damage to the sensor or probe.

Considerations

Monnit sensors are accurate to +/- 1°C with default calibration. Therefore you can rely on the data reported by your sensor with high reliability. This is even the case when you suspect the Monnit sensor is not reporting accurate temperatures. The vast majority of the time, the sensor is reporting accurate temperatures, and it is best to approach the readings with this in mind. The most common scenario that leads to questions about the Monnit Temperature sensor readings are related to environment factors. The following articles may be helpful in identifying these factors.

• Freezer Defrosters and Monnit Sensors
• Environmental Factors Affecting Sensors

Steps

1. Retrieve two operating sensors.
2. Reset the calibration to Default by clicking the Default button under the Calibrate tab.
3. Allow the sensors to check in and accept the default calibration. You may want to wait a few check ins to make sure the default calibration is accepted.
4. Power both sensors off.
5. Configure both sensors to have a Heartbeat and Aware State Heartbeat with the same frequency. It may be advisable to configure both sensors with a 10 minute Heartbeat (if you have a Premiere subscription) so you have a more frequent and larger sample size and with the same Aware State Threshold.
6. Place the sensors in position such that the probes of each sensor are in immediate proximity to each other (within an inch or more is best). This is important for identifying if there is a defrosting unit that is affecting the readings.
7. Power the sensors on at the same time. Being sure the sensors are powered up at the same time will eliminate time factors involved in temperature changes and is key to identifying patterns.
8. Once the sensors accept the Heartbeat configurations, you should see them checking in at the same intervals. Compare the temperature readings which would should be expected to yield temperature reading within 2°C of each other (+/- 1°C on each sensor).

Conclusion

After 90 minutes of readings, we would expect to see the readings of both sensors to track within 2°C of each other. Be sure the sensors have the default calibration set, as this will help identify if additional calibration may be needed. Feel free to contact support@monnit.com with related inquiries.