Power and Charging

The device operates from one or two 18650 cells and charges through USB Type-C. The power source can be a charger, a power bank, or an optional solar panel.

Choosing a charger and cable

The device does not support fast charging, including USB Power Delivery (PD). Use a standard power source with a USB Type-A port and a USB Type-A–USB Type-C cable. A USB Type-C–USB Type-C cable is not recommended for charging.

Open USB Type-C power port

Close the protective port cover after charging:

Closed protective cover over the power port

the blue indicator remains lit when the battery is fully charged and external power is still connected;
the charge level is shown in SMS messages and in the general settings of the web interface;

Battery charge in the web interface

below 20%, the device enters power-saving mode, stops regular measurements and SMS messages, and periodically checks the charge level;
after a critical discharge, the battery disconnects automatically, and time synchronization may be required after charging.

After long-term storage

If the battery voltage is below 3.5 V, do not try to restore the device using only its USB port. Follow the recovery procedure after long-term storage.

Danger

Do not use the device without an installed 18650 cell. Observe the polarity strictly when replacing it: incorrect polarity will damage the device.