Device for electroinically connecting and disconnecting portions of an electrical line, public address system, method for detecting a failure in an electrical line

A public address system comprising:

• a plurality of connecting/disconnecting devices including:
• a switch configured to electrically connect and disconnect a first and a second contact point, wherein the first and the second contact point are configured to be electrically connected to respective portions of the electrical line,
• a controller configured to control the switch based on at least one electrical characteristic at the first and/or second contact point, and
• a power supply configured to be electrically connected to the first contact point via the switch,
• wherein the switch is configured to switch between:
• (a) a first configuration where the first contact point and the power supply are electrically connected with each other while the first and the second contact point are electrically disconnected from each other, and
• (b) a second configuration where the first contact point and the power supply are electrically disconnected while the first and the second contact point are electrically connected with each other, and
• an electrical line comprising a plurality of portions connecting the plurality of connecting/disconnecting devices to each other,
• a plurality of loudspeakers connected in parallel to the line, and
• an output module connected to the electrical line and configured to output an audio signal to the electrical line.

A method for detecting a failure in an electrical line of the public address system, the method comprising:

• switching a switch configured to electrically connect and disconnect a first and a second contact point, wherein the first and the second contact point are configured to be electrically connected to respective portions of the electrical line, from a second configuration into a first configuration upon detecting an interruption of the pilot signal, wherein the first configuration is where the first contact point and a power supply are electrically connected with each other while the first and the second contact point are electrically disconnected from each other, and wherein the second configuration is where the first contact point and the power supply are electrically disconnected while the first and the second contact point are electrically connected with each other,
• applying by the respective power supply electrical power to the respective portions of the electrical line via the respective first contact points,
• measuring at least one electrical characteristic at the first and/or the second contact points in order to determine the absence of a short-circuit and/or a line breakage in the respective portion of the electrical line;
• and
• either:
• switching from the first configuration into the second configuration, if the measured characteristic detects the absence of a short-circuit and/or a line breakage in the respective portion of the electrical line,
• or disconnect the first and second contact point and the power supply electrically from each other if the measured characteristic detects a short-circuit and/or a line breakage in the respective portion of the electrical line.