Protistor® high-speed fuse with a square ceramic body, striker indication system, flush metric-threaded ends, rated for 315A at 1250VAC IEC and 1300VAC UL standards, designed for semiconductor protection.
£140.33
The Mersen B300519 is a premium square body high-speed semiconductor fuse engineered to provide reliable protection for sensitive power electronic components. Manufactured as part of the trusted Mersen Protistor® range, this fuse is specifically designed to safeguard semiconductors including IGBTs, thyristors, diodes and rectifiers used in demanding industrial power conversion systems.
Designed for high-performance applications, the B300519 delivers ultra-fast fault interruption, helping minimise damage caused by short circuits while reducing equipment downtime. Its robust square body construction, silver-plated contacts and striker indicator provide dependable operation in critical industrial environments.
With a 315 A current rating and a 1250 V AC IEC / 1300 V AC UL voltage rating, the Mersen B300519 is ideally suited for drives, UPS systems, renewable energy equipment, industrial converters and other semiconductor protection applications requiring rapid fault clearance.
High-speed semiconductor fuses are specifically designed to protect sensitive electronic power devices from damaging fault currents. Their ultra-fast operating characteristics help minimise energy let-through, reducing the risk of costly failures and extending equipment service life.
The Mersen Protistor® range is widely used in industrial automation, renewable energy systems and power conversion equipment where dependable semiconductor protection is essential. The B300519 offers proven performance for modern electrical installations operating under demanding conditions.
| Item number | B300519 |
|---|---|
| Catalogue No | PC71UD13C315TF |
| Description | Square Body High-Speed Fuse Protistor® Size 71 aR 1250VAC IEC 1300VAC UL 315A With Striker Flush ends metric threads |
| EAN/UPC Code | 3605340329711 |
| Rated voltage AC UL | 1300 V |
| Rated voltage AC IEC | 1250 V |
| Ampere Rating | 315 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 71 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 129 kA²s |
| Melting I2t | 16 kA²s |
| AC Max I.R./Breaking Capacity | I1: 126 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Brass |
| Connection/Terminal Type | Flush ends |
| Product Width | 51 mm |
| Product Length | 74 mm |
| Product Height | 56.5 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 1.545 kg |
| Sell Pack Width | 90 mm |
| Sell Pack Length | 170 mm |
| Sell Pack Height | 70 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 0.515 kg |
| Power Dissipation at Rated Current Value | 73 W |
| HS Code | 85351000 |
The B300519 protects power semiconductors such as IGBTs, thyristors, diodes and rectifiers from damaging short-circuit currents.
This fuse has a 315 A current rating.
It is rated for 1250 V AC (IEC) and 1300 V AC (UL).
The aR characteristic provides ultra-fast protection for semiconductor devices while allowing controlled overload capability where appropriate.
It is commonly installed in industrial drives, power converters, UPS equipment, renewable energy systems and other semiconductor-based power electronics.
Mersen Protistor® high-speed semiconductor fuses are trusted across industrial automation, energy and power conversion industries to provide fast, dependable protection for valuable semiconductor equipment.
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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...