High-speed fuse designed for protecting power semiconductors with rapid fault interruption, striker indication system, and open slot blade terminals. Rated 630A, 1250VAC IEC, 1300VAC UL.
£263.59
The Mersen B300634 is a high-performance square body high-speed semiconductor fuse developed to protect sensitive power electronic components against damaging short-circuit currents. Part of the established Mersen Protistor® high-speed fuse range, it is designed for industrial systems containing IGBTs, thyristors, power diodes, rectifiers and other semiconductor devices.
Featuring an ultra-fast aR operating characteristic, the B300634 interrupts severe fault currents rapidly and limits the electrical energy allowed to pass through the circuit. This helps protect valuable semiconductor assemblies, reduce equipment damage and minimise unplanned downtime in demanding power conversion applications.
With a rated current of 350 A and voltage ratings of 1250 V AC under IEC standards and 1300 V AC under UL standards, the Mersen B300634 is suitable for industrial drives, converters, inverters, uninterruptible power supplies and renewable energy equipment requiring dependable high-speed protection.
Power semiconductor components can be permanently damaged by fault currents before a conventional industrial fuse has time to operate. The Mersen B300634 is engineered to respond rapidly during short-circuit conditions, restricting peak current and total energy let-through to help preserve sensitive electronic devices.
Its partial-range aR characteristic is specifically intended for semiconductor short-circuit protection. Correct fuse selection should include confirmation of the current rating, voltage rating, breaking capacity, operating class, terminal arrangement and physical dimensions against the equipment manufacturer’s documentation.
| Item number | B300634 |
|---|---|
| Catalogue No | PC73UD13C630EF |
| Description | Square Body High-Speed Fuse Protistor® Size 73 aR 1250VAC IEC 1300VAC UL 630A With Striker Open Slot Blades |
| EAN/UPC Code | 3605340331356 |
| Rated voltage AC UL | 1300 V |
| Rated voltage AC IEC | 1250 V |
| Ampere Rating | 630 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 73 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 680 kA²s |
| Melting I2t | 84 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 | Open Slot Blades |
| Product Width | 73 mm |
| Product Length | 149.4 mm |
| Product Height | 78.5 mm |
| Sell Pack Quantity | 1 EA |
| Sell Pack Weight | 1.11 kg |
| Sell Pack Width | 110 mm |
| Sell Pack Length | 180 mm |
| Sell Pack Height | 80 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 1.11 kg |
| Power Dissipation at Rated Current Value | 132 W |
| HS Code | 85351000 |
The Mersen B300634 is used to protect sensitive semiconductor components against damaging short-circuit currents in industrial power electronic equipment.
The Mersen B300634 has a rated current of 350 A.
The fuse is rated for 1250 V AC under IEC standards and 1300 V AC under UL standards.
The aR classification identifies an ultra-fast partial-range fuse designed primarily to provide short-circuit protection for semiconductor devices.
It is commonly installed in industrial drives, converters, inverters, UPS systems, renewable energy equipment and other semiconductor-based power systems.
Mersen Protistor® high-speed fuses are widely used by electrical engineers, equipment manufacturers and maintenance professionals to protect valuable semiconductor components in demanding power conversion systems.
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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...