Surge Protective Devices for Power Supply System Protection

NOTE 1:  BACKUP FUSE VALUE

NOTE 2: INSTALLATTION ATTENTION

The device may only be connected and installed by an electrically skilled person conforming to National Standards and safety regulations. Fuse must be installed at the upstream of the SPD or the lightning arrester for power supply system to makesure that the protected system has double protection. The value of the fuse used in a SPD system should be conformed to:

 1, The value of the fuse should not be larger than the max. withstand capacity of the SPD’s backup fuse value.

 2, Under the status of the max. current in the power supply & close loop circuit available current, the fuse should be able to disconnect when overloaded or shortcircuited.

 3, Taken (1) & (2) into consideration, the fuse should be able to conduct the maximum surge discharge of the SPD.

Some fuse & circuit breaker manufacturers can quote/have quoted 8/20μs and/or 10/350μs current specification, therefore, installers can specify the type accordingly with the SPD current requirement.