S&C Power Fuses Overview
S&C Power Fuses, specifically Types SMD-20 and SMD-40, are designed for outdoor distribution ranging from 4.8 kV to 34.5 kV. These fuses are compatible with SMU Fuse Units and are now available in factory-assembled, three-phase cluster mountings, which streamline installation and ensure proper fuse adjustment.

Connector Options
Two types of connectors are available for SMD-20 and SMD-40 mountings:

• Bronze Body, Tin Plated: Accommodates No. 2 solid through 500 kc mil stranded copper or aluminum, or 397.5 kc mil ACSR.
• Aluminum-Alloy Body, Tin Plated: Similar conductor accommodation as the bronze option.

Mounting Details

• SMD-20: Available for 14.4 kV, 25 kV, and 34.5 kV with interrupting capacities up to 14,000 amperes.
• SMD-40: Available for 4.8 kV, 14.4 kV, and 25 kV with interrupting capacities up to 25,000 amperes.

Both types can be equipped with optional Loadbuster® attachment hooks.

Additional Information
Symmetrical ratings are based on short-circuit current availability with an X/R ratio of 15. Higher ratings are available for specific conditions, detailed in S&C Descriptive Bulletin 242-32. Connectors can be specified by adding a suffix to the catalog number.