Mersen’s Medium Voltage Controllable Fuse (MVCF) 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 minimal installation downtime and ownership maintenance.
Mersen developed the MVCF 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/cm2, which is too high for PPE, requiring owners to prevent access to those areas unless power is disconnected. This is typically unworkable and does not mitigate the hazard. Visit Mersen’s Arc Flash Info Center for additional information.
Features and benefits:
- Fuses fit into existing clips and space. The retrofit can be completed in minutes, provided fiber optic cable is already in place.
- Lowest-cost arc-flash mitigation solution. A turnkey installation of the MVCF will cost a fraction of other available alternatives.
- Exceptional performance.
- 50kA short circuit interrupt rating.
- Fast response time mitigates the arc-flash energy to Category 2 PPE.
- Low maintenance. Fuses are designed to last 20 years with no maintenance intervals, and the battery lasts for three years.
- Flexible design interface. Designed to be used with a variety of conventional arc-flash detection devices and relays.
- No nuisance-tripping. Actuator modules are programmed to ignore trip signals when primary current is below the fuse rating.
- Automatically performs a weekly system check. Confirms continuity on all FO lines.
- Minimal stress on other devices. The fuse element softens the voltage spike that occurs when opening. Alternatives may generate an excessive spike that could damage transformer insulation or upstream devices.
- Small back-up power cells. The MVCF utilizes small batteries that fit inside the Controllable Fuse Actuator Module (CFAM) versus other solutions requiring multiple lead-acid car batteries
How does the MVCF’s Intelligent Fuse System work?
- The Mersen MVCF operates like a normal MV fuse under short circuit and overload situations. When connected to an Arc-Flash detection system that is properly set up, the MVCF will open the circuit in time to limit the hazard to Category 2 PPE.
- The Mersen MVCF System’s Interface Module (CFIM) is mounted in the low voltage area and accepts a trip signal from the customer’s existing arc-flash detection relay.
- The CFIM immediately sends a signal over fiber-optic cables to the Actuator Modules (CFAM) attached to the bottoms of the fuses in the medium voltage cabinet.
- The CFAM then causes a switch within the fuse to open. This shunts the current through a much smaller fuse element that opens the circuit in a controlled manner.
To learn how you can use Mersen’s MVCF to help cost-effectively mitigate arc-flash hazards, contact your French Gerleman representative.