Mersen introduces the Medium Voltage Controllable Fuse

June 15, 2015
Breakthrough arc flash protection

Mersen is pleased to announce the next step in fuse technology: an intelligent, controllable fuse for medium voltage applications. The Mersen Medium Voltage Controllable Fuse(MVCF) provides arc flash protection with a plug-in retrofit to existing MV fuses at a low total cost and minimal installation downtime and ownership maintenance.

Mersen's Medium Voltage Controllable Fuse System is designed to mitigate the arc-flash hazard on the low-voltage side of a medium voltage transformer. The industry's first fuse to provide normal short-circuit and overload protection while having the capability to open on command, this fuse is a cost-effective arc flash solution with Mersen developed the Medium Voltage Controllable Fuse in response to OSHA Code 29 CFR-1910 Subpart S, requiring employers to identify and analyze arc-flash hazards and provide adequate personal protective equipment (PPE). For many installations, the arc-flash energy is over 40 cal/cm2requiring owners to prevent access to those areas unless power is disconnected. This is typically unworkable and In a typical plant, the power feeding a 480V main breaker panel in an industrial facility comes from a local 15.5kV transformer protected by upstream fuses. The only protection between the load-side of the transformer and the line-sides of the main breakers is the MV fuse or CB on the line-side of the transformer.

The line-sides of the main low voltage breakers have potential for arc-flash energies well beyond the capabilities of any PPE. The reason for this is that the closest upstream protective device is usually a medium voltage fuse on the primary side of the transformer. This fuse is designed to provide short circuit and overload protection without opening during the normal transformer in-rush current.

"Mersen's Medium Voltage Controllable Fuse provides a unique approach to arc flash mitigation incorporating innovative and patented technology at low cost and unmatched ease of installation into conventional switch gear," states Rich Puffer, Mersen's VP General Manager, Standard Products, North America.