Description
Overview
The Eaton Bussmann 280MMT is a 280A double barrel high speed fuse from the Bussmann MMT series, engineered specifically for semiconductor protection in demanding industrial power electronics. Rated 690V AC and 450V DC with a 200 kA breaking capacity, this Class aR fuse provides the rapid fault clearance required to safeguard SCRs, IGBTs, diodes, and other semiconductor devices before they reach thermal destruction limits. Compliant with BS88 Part 4 and IEC 60269-4, it is an industry-trusted choice for panel builders, OEMs, and maintenance engineers across India.
Key Features
- Class aR Semiconductor Protection — purpose-built fast-acting characteristic that clears faults in microseconds, protecting expensive semiconductor devices from thermal runaway
- 200 kA Breaking Capacity — handles extreme prospective fault currents in high-power industrial installations without failure
- Dual Voltage Rating (690V AC / 450V DC) — suitable for both AC drive systems and DC bus applications within a single fuse platform
- Double Barrel Form Factor — compact parallel-barrel construction delivers consistent arc-quenching performance and reliable contact across both terminals
- BS88 Part 4 / IEC 60269-4 Compliance — meets internationally recognised semiconductor fuse standards ensuring interchangeability and application safety
- CE Marked and RoHS Compliant — meets European directives for electromagnetic compatibility, safety, and restriction of hazardous substances
- IEC Rated and UL Recognised — dual certification supports both global export equipment and domestic Indian panel builds
- Bussmann MMT Series Pedigree — proven platform widely specified by drive and converter OEMs for consistent lot-to-lot performance
Technical Specifications
| Specification | Value |
|---|---|
| Catalog Number | 280MMT |
| Series | Bussmann MMT |
| Amperage Rating | 280 A |
| Rated Voltage AC | 690 V |
| Rated Voltage DC | 450 V |
| Breaking Capacity | 200 kA |
| Fuse Class | Class aR |
| Fuse Type | High Speed British Standard Double Barrel |
| Standard | BS88 Part 4, IEC 60269-4 |
| Compliances | CE Marked, RoHS Compliant |
| Certifications | IEC Rated, UL Recognized |
| Application | Semiconductor protection, DC drives, VFDs, power converters, rectifiers, soft starters, thyristor stacks, DC common bus |
Applications & Selection Guide
The 280MMT is the correct choice when you need to protect semiconductor switching devices — SCRs, thyristors, IGBTs, and power diodes — in medium to high power converters operating at up to 690V AC or 450V DC. The Class aR rating means this fuse is not a general-purpose backup fuse; it is optimised exclusively for semiconductor protection and will clear prospective fault currents within the I²t limits that semiconductor datasheets specify. Always verify that the fuse let-through I²t is less than the withstand I²t of the semiconductor being protected.
Typical Indian industrial applications include variable frequency drives (VFDs) in textile mills, cement plants, and steel rolling mills; rectifier panels in electroplating and electrolysis lines; soft starter panels in water treatment pumping stations; and regenerative DC drive systems in paper and printing machinery. The 280A rating suits medium power drive modules commonly found in 75 kW to 200 kW converter stages at standard Indian 415V / 690V distribution voltages.
When specifying for DC common bus architectures — increasingly common in multi-axis CNC and robotics installations across Coimbatore’s manufacturing belt — the 450V DC rating and 200 kA breaking capacity ensure this fuse meets both the voltage and fault energy demands of modern bus-coupled drive topologies. Panel builders should cross-check fuse holder and carrier compatibility within the MMT series range before finalising the design.
Why Buy from Shansen Enterprises?
- Authorized Eaton Channel Partner in Coimbatore — supply chain direct from Eaton India
- 100% genuine Eaton Bussmann products with manufacturer warranty
- Pan-India delivery — Coimbatore, Chennai, Bengaluru, Mumbai, Pune, Hyderabad, and beyond
- WhatsApp technical support for application selection, sizing, and replacement cross-reference
- Bulk and project pricing for panel builders, OEMs, and EPC contractors
Compatible Products & Accessories
- Eaton Bussmann MMT Series Fuse Holders and Carriers (matching double barrel format)
- Eaton Bussmann DIN-rail and panel-mount fuse bases for MMT series
- Eaton Bussmann semiconductor fuse indicators and blown-fuse signal accessories
- Eaton Bussmann complementary Class aR fuses in adjacent current ratings (250A, 315A, 355A MMT series)
- Eaton drive protection coordinated fuse kits for VFD and soft starter panels
- Copper bus bar connection kits and torque-rated terminal hardware for 280A fuse installations
Frequently Asked Questions
What is the difference between a Class aR fuse and a Class gG fuse for drive protection?
A Class gG fuse is a general-purpose full-range fuse designed to protect cables and switchgear from both overloads and short circuits, but its clearing time is too slow to protect semiconductor junctions. A Class aR fuse like the 280MMT is a partial-range fuse optimised exclusively for semiconductor protection — it clears high-magnitude fault currents in microseconds, within the thermal withstand limits of SCRs, IGBTs, and diodes. Class aR fuses must always be used in conjunction with a backup overcurrent device that covers the overload region the aR fuse does not protect.
Can the 280MMT be used on a 415V AC system in India?
Yes. The 280MMT is rated for 690V AC, so it is fully suitable for use on standard Indian 415V AC (line-to-line) industrial distribution systems. Operating a fuse at a voltage below its rated voltage does not affect its protection performance; the rated voltage is the maximum safe operating voltage, not a minimum requirement.
What does the 200 kA breaking capacity mean for my panel design?
Breaking capacity (also called interrupt rating) is the maximum prospective fault current the fuse can safely interrupt without rupturing or causing a hazard. A 200 kA rating means the 280MMT can clear fault currents up to 200,000 amperes at its rated voltage. For most Indian industrial installations fed from medium voltage transformers, the available fault current at the drive panel is well below 200 kA, so this fuse provides a comfortable safety margin. Always confirm the actual prospective fault current at the point of installation from your power system study or transformer short-circuit data.
Is the 280MMT suitable for both AC drives and DC common bus applications?
Yes. The 280MMT carries a dual voltage rating — 690V AC and 450V DC — making it suitable for semiconductor protection in both AC variable frequency drives and DC common bus architectures. For DC applications, ensure the actual DC bus voltage does not exceed 450V DC. In regenerative or active front-end converter designs, the DC bus voltage can sometimes exceed the nominal level, so always verify peak DC bus voltage against the 450V DC fuse rating during system design.
How do I verify the correct I²t coordination between the 280MMT and my semiconductor device?
Obtain the maximum let-through I²t value of the 280MMT from Eaton Bussmann’s published time-current and I²t curves for the MMT series at your operating voltage. Then compare this value against the rated withstand I²t (also called I²t for fusion) published in your semiconductor device datasheet — typically provided by the SCR or IGBT module manufacturer. The fuse let-through I²t must be less than or equal to the semiconductor withstand I²t to ensure the fuse clears the fault before the device is damaged. Shansen Enterprises can assist with I²t coordination checks — contact us via WhatsApp with your drive or converter module part number.
How do I order the Eaton Bussmann 280MMT from Shansen Enterprises?
You can request a quote for the Eaton Bussmann 280MMT directly from Shansen Enterprises in Coimbatore by clicking the WhatsApp button on this page or sending an email with your catalog number (280MMT), required quantity, and delivery location. Our team will respond with pricing, availability, and estimated delivery timeline. We supply genuine Eaton Bussmann products with full manufacturer warranty to customers across India including Chennai, Bengaluru, Mumbai, Pune, Hyderabad, and all major industrial cities.
