Alarm system controller configured to be connected to a wired bus divided into a plurality of segments by means of a plurality of separator devices each including an energy storage means, the alarm system controller comprising: a power module for supplying power through the bus to the separator devices; a communication module for performing a bidirectional digital communication through the bus with the separator devices; and a monitoring module for monitoring the electrical current supplied through the bus, while charging the energy storage means using the power supplied through the bus; wherein the alarm system controller further includes: an initialisation module for initialising the alarm system, wherein the initialisation module is configured to control: the power module so as to temporarily increase an electrical voltage supplied through the bus above a first threshold to the high voltage level, for triggering an internal initialization process of at least one out of the plurality of separator modules and to charge the corresponding energy storage means; the monitoring module so as to determine whether more than one separator device has started the internal initialization process, depending upon whether the electrical current supplied to the bus exceeds a second threshold or not; and the communication module to perform an initialization communication with a separator device, which has started the internal initialization process, if only one separator devices has started the internal initialization process; wherein the initialisation module is configured to perform an exception initialization process, if the monitoring module has determined that more than one separator device has started the internal initialization process. a power module for supplying power through the bus to the separator devices; a communication module for performing a bidirectional digital communication through the bus with the separator devices; and a monitoring module for monitoring the electrical current supplied through the bus, while charging the energy storage means using the power supplied through the bus; wherein the alarm system controller further includes: an initialisation module for initialising the alarm system, wherein the initialisation module is configured to control: the power module so as to temporarily increase an electrical voltage supplied through the bus above a first threshold to the high voltage level, for triggering an internal initialization process of at least one out of the plurality of separator modules and to charge the corresponding energy storage means; the monitoring module so as to determine whether more than one separator device has started the internal initialization process, depending upon whether the electrical current supplied to the bus exceeds a second threshold or not; and the communication module to perform an initialization communication with a separator device, which has started the internal initialization process, if only one separator devices has started the internal initialization process; wherein the initialisation module is configured to perform an exception initialization process, if the monitoring module has determined that more than one separator device has started the internal initialization process. the power module so as to temporarily increase an electrical voltage supplied through the bus above a first threshold to the high voltage level, for triggering an internal initialization process of at least one out of the plurality of separator modules and to charge the corresponding energy storage means; the monitoring module so as to determine whether more than one separator device has started the internal initialization process, depending upon whether the electrical current supplied to the bus exceeds a second threshold or not; and the communication module to perform an initialization communication with a separator device, which has started the internal initialization process, if only one separator devices has started the internal initialization process; wherein the initialisation module is configured to perform an exception initialization process, if the monitoring module has determined that more than one separator device has started the internal initialization process.