T 4.18 Discharged or fatigued emergency power supply in answering machines

Answering machines with a digital memory are equipped with a battery or accumulator which allows the memory contents to be retained in case of a power failure. If the capacity of the battery or accumulator is exhausted before the end of a power failure, this generally results in the deletion of the outgoing message and, in the case of digital recordings, the messages already in the memory.