High-speed Protistor® fuse providing fast and reliable circuit protection at 350A with advanced aR characteristic and integrated striker for remote indication.
£247.12
The Mersen B300565 is a premium square body high-speed semiconductor fuse engineered to provide maximum protection for sensitive power electronic equipment. Part of the renowned Mersen Protistor® Size 73 series, this fuse is specifically designed to protect semiconductors including IGBTs, thyristors, diodes and rectifiers used in industrial power conversion applications.
Designed for demanding industrial environments, the B300565 delivers ultra-fast fault interruption to minimise damage caused by short circuits while reducing costly downtime. Its robust square body construction, silver-plated contact surfaces and integrated striker indicator ensure dependable performance throughout its service life.
With a rated current of 350 A and a 1250 V AC IEC / 1300 V AC UL voltage rating, the Mersen B300565 is ideal for protecting variable frequency drives, UPS systems, industrial converters, renewable energy equipment and other high-performance semiconductor applications.
High-speed semiconductor fuses are specifically designed to interrupt fault currents before they can damage expensive power electronic components. Their low let-through energy helps extend equipment life while reducing maintenance costs and improving overall system reliability.
The Mersen Protistor® Size 73 range has been developed for modern industrial power conversion systems, offering dependable protection for drives, converters, UPS equipment and renewable energy installations where semiconductor protection is critical.
| Current | 11 A |
|---|---|
| Item number | B300565 |
| Catalogue No | PC73UD13C350D1A |
| Description | Square Body High-Speed Fuse Protistor® Size 73 aR 1250VAC IEC 1300VAC UL 350A With Striker DIN 110 Blades |
| EAN/UPC Code | 3605340330342 |
| Rated voltage AC UL | 1300 V |
| Rated voltage AC IEC | 1250 V |
| Ampere Rating | 350 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 73 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 140 kA²s |
| Melting I2t | 17 kA²s |
| AC Max I.R./Breaking Capacity | I1: 126 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Copper |
| Connection/Terminal Type | DIN 110 Blades |
| Product Width | 73 mm |
| Product Length | 133.4 mm |
| Product Height | 78.5 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 3.36 kg |
| Sell Pack Width | 150 mm |
| Sell Pack Length | 250 mm |
| Sell Pack Height | 90 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 1.12 kg |
| Power Dissipation at Rated Current Value | 86 W |
| HS Code | 85351000 |
The B300565 protects semiconductor devices including IGBTs, thyristors, rectifiers and diodes from damaging short-circuit currents.
This fuse has a 350 A rated current.
It is rated for 1250 V AC (IEC) and 1300 V AC (UL).
The aR characteristic provides ultra-fast protection specifically for semiconductor devices by limiting fault energy during short-circuit conditions.
The fuse is commonly installed in industrial drives, power converters, UPS systems, renewable energy equipment and other semiconductor-based power electronics.
Mersen Protistor® high-speed semiconductor fuses are trusted worldwide to provide reliable protection for valuable power electronic equipment in industrial automation, energy and power conversion applications.
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LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...