A communications module (2) adapted for use with a defibrillator, comprising a power supply system configured to supply power to the communications module, a power connector adapted for connection to the defibrillator to provide power from the communications module to the defibrillator, a power switch connected between the power supply system and the power connector to transmit power from the power supply system to the power connector, a data connector adapted for connection to the defibrillator to transfer defibrillator data between the defibrillator and the communications module, and a processor configured to control the power switch to provide power from the communications module to the defibrillator to enable the transfer of the defibrillator data between the defibrillator and the communications module.
