The battery life is up to. 45,000 operations (open/close) or 4 years.
Please note that the battery life can be considerably shortened, especially at low temperatures.

In ONLINE operation with AccessManager, the battery status can be reported by e-mail.
In OFFLINE mode, the message is displayed optically/acoustically on the cylinder for the last approx. 1,000 messages.

A battery change is possible without disassembly in the installed condition. The knob contains two standard CR2 (3V) lithium batteries.