CABLE NETWORK POWER UNIT FOR SURGE PROTECTOR RELEASE

摘要

There is provided a cable network power unit (22) configured to generate a DC power signal periodically switching between a positive and negative voltage, the power unit (22) comprising a polarity switching module (66), current measuring device (60), and a controller (64), wherein the controller (64) is responsive to abrupt changes in current to trigger the polarity switching module (66) to switch polarity of the DC power signal, and thereby reset surge protectors in active devices such as nodes or amplifiers if they have triggered due to a power surge, for example from a lightning strike.