WHY BATTERY LEVEL VARIES IN ZOOMFAB SENSORS
Why Battery Level varies in ZOOMFAB sensors
ZOOMFAB sensors take a sample of the battery voltage to interpret battery level. The voltage of the battery in your sensor is sampled in 10-minute intervals. When the sensor's transmitter is active, the battery is under the heaviest load. As a result, the battery level can vary quite a bit while it is under the load, and thus the battery level reported in the software will reflect this.
If we measure the battery while it is not under load, we get the impression that the health of the batter is in better shape than it really is. This is why we measure the battery voltage under load, as it gives a more accurate representation of the condition of the battery. While it does mean that the battery level reported on different times may vary, the overall picture of the battery health is more accurate.
Life of batteries warry depending on two factors – frequency of reporting (machines with frequent cycles) and an environment (ambient temperature, connection distance, noise)
Battery life expectancy is between 2 and 6 years for sensors measuring current and activities with cycles around 1 minute or more). Sensors, which monitor short activities and pulses, may last between 1 and 2 years.