COORDINATION OF FUSES AND OVERVOLTAGE PROTECTION DEVICES IN LOW-VOLTAGE MAINS

摘要

Fuses are used together with arresters in different types of overvoltage protection devices for low-voltage mains. The requirements on lv fuses which are installed in cascaded surge protection devices at the entrance of buildings are discussed. Experimental investigations on different sizes of lv fuses with lightning single pulse currents (10/350 μs) up to 80 kA deliver the behaviour of fuses in the prearcing phase. From this the permissible lightning pulse currents and the matching short-circuit currents were determined.