When dealing with battery powered wireless sensors, there are many factors that can affect the life span of the battery. We have compiled a list of useful tips to help you understand wireless sensor power management and improve the life of your wireless sensors’ batteries.

Battery Power Options
Monnit provides a great wireless sensor product with a small footprint, allowing our sensors to be placed inconspicuously so they do not draw attention. In order for us to achieve this small footprint, our standard wireless sensors are powered by a CR2032 coin cell battery. The provided coin cell battery provides 225 milli-amp hours (mAh). If you require a longer battery life for your application, we currently provide a AA battery option for our wireless sensors that provide 3,000 mAh (~10 times the battery life).

Frequency of Transmissions
How frequently your wireless sensors transmit (heartbeat) can have a severe impact on the life of the battery. A Monnit WIT wireless sensor with a standard coin cell battery transmitting once an hour will last approximately 2-4 years depending on environmental conditions. If you want to preserve the battery life of your wireless sensor, set the heartbeat (transmission interval) as high as your specific application will allow for.

Temperature Conditions
Batteries are electrochemical devices which convert chemical energy into electrical energy. Extremes in temperature can cause the chemical characteristics of the battery to change, causing the battery to burn power faster when hot or not generate enough current when cold. In order to maximize the battery life of your wireless sensors, keep them as close to room temperature as possible (°60 F – °70 F).

Radio Interference and Transmission Retries
The radio transmission of your wireless sensors is a two part process. The sensor transmits its data to the Wireless Gateway Transceiver then listens for a reply transmission to acknowledge that the signal was received. When there is a significant amount of radio noise or interference, your wireless sensors may have to transmit longer in order to send and listen through the interference. If the signal is not received and acknowledged, the sensor will try to transmit again until it receives a successful response. Both of these issues can have an impact on battery life. Monnit wireless sensors operate on the 900MHz frequency that is less crowded than the popular 2.4GHz and higher frequencies, so you already should expect less interference using Monnit WIT Wireless Sensors. To ensure optimal performance of your sensors and batteries, try to avoid areas that have an excess of radio interference from other devices.