POLARITY SWITCHING CIRCUIT AND FEEDING UNIT

摘要

A polarity switching circuit capable of adding a DC power source to a feeding line with a correct polarity without requiring a check of the polarity of a feeding system connected to a load. The polarity switching circuit lies between the DC power source and the load and connects the DC power source to two feeding conductors connected to the load. Four switches are bridge-connected between two input terminals connected to the DC power source and two output terminals connected to the feeding conductors. Two switches are turned on and the remaining two switches are turned off depending on the polarity of the feeding conductor connected to the first output terminal.