Technical details about energy management

The device will work until 3,4 V as intended, if the 4-Channel Data Logger is operated without an external supply or charging voltage (V IN). The modem is deactivated from this threshold and the "UV MODEM LOCKOUT" log entry is entered in the device log. This means that the connection is disconnected if the device is in "online" mode or is logged in to the mobile network ("Interval & wakeup" mode).

Only once the internal supply voltage falls below 2,9 V , does the 4-Channel Data Logger switch to energy saving mode in which only the charge control is active. In this case, the charge control tries to charge the rechargeable battery up to 3,8 V . The "UV_LOCKOUT" log entry is also entered in the device log when activating energy saving mode. The rechargeable battery of the power supply unit can be recharged again if the device is in energy saving mode and an external supply or charging voltage (V IN) is connected. Otherwise the 4-Channel Data Logger remains in this energy saving mode until the rechargeable battery is completely discharged.

Energy saving mode is terminated and all of the functions except for the communication with the myDatanet server are resumed, once the rechargeable battery voltage exceeds 3,2 V when recharging. The modem continues to remain inactive until the rechargeable battery voltage exceeds 3,5 V . Only then can a mobile network connection be established again and the device resumes normal operation.

When an external supply or charging voltage (V IN) is used, the charge control ensures that the rechargeable battery of the power supply unit is charged. The following operating states are possible:

  • Active energy saving mode :

    The charge control tries to charge the rechargeable battery to 3,8 V or to maintain the voltage at this level.

  • Active mode:

    The functionality of the charge control can be selected via the "Charging mode" parameter. This is located in the "Basic settings" configuration section (see Basic settings). There are three options available:

    • Off: Charge control deactivated

    • Normal: The charge control is activated and the rechargeable battery is charged to the maximum voltage if the state of charge of the rechargeable battery for the power supply unit falls below 50%. The charge control is then deactivated again. This is designed to optimise the service life of the rechargeable battery.

    • Solar: The rechargeable battery of the power supply unit is charged to the maximum voltage if the supply or charging voltage V IN exceeds 16 V . The charge control then remains deactivated for 12 hours unless the state of charge of the rechargeable battery for the power supply unit drops below 95%. This charge strategy is recommended if a solar field is used to charge the rechargeable battery.

The charge control reads out any additional information that is required, such as the maximum voltage and ambient temperature at which charging is permitted, directly from the memory of the power supply unit. In both charge strategies, recharging is only completed if the ambient temperature does not exceed the permissible range of the charging temperature. The permissible charging temperature is specified in the factsheet for the relevant power supply unit. Chapter Power supply units contains an overview of the temperature ranges of the power supply units.