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MERSEN FUSE A 070 URD 31 LI 0500 A070URD31LI0500
High-speed fuse providing reliable protection for semiconductor and power conversion applications with integrated striker indication and slotted blade terminals.
£103.08
Why Choose the Mersen B300703 High-Speed Semiconductor Fuse?
The Mersen B300703 is an industrial high-speed semiconductor fuse designed to protect sensitive power electronic components against damaging short-circuit currents. Manufactured by Mersen, it is suitable for electrical systems containing IGBTs, thyristors, power diodes, rectifiers and other semiconductor devices that require rapid fault interruption.
Unlike conventional industrial fuses, high-speed semiconductor fuses are engineered to limit the peak current and electrical energy passing through a circuit during a fault. This fast response helps reduce thermal stress on valuable components, minimise equipment damage and improve the reliability of power conversion and automation systems.
The B300703 is intended for professional maintenance and replacement applications where the fuse must be matched precisely to the original equipment specification. It is suitable for use in industrial drives, converters, inverters, uninterruptible power supplies and other semiconductor-based equipment requiring dependable short-circuit protection.
Key Advantages
- High-speed semiconductor protection fuse for industrial power electronics.
- Rapid short-circuit interruption helps minimise damaging energy let-through.
- Suitable for protecting IGBTs, thyristors, diodes and rectifiers.
- Helps reduce equipment damage, maintenance requirements and unplanned downtime.
- Industrial construction for dependable performance in demanding applications.
- Manufactured by Mersen, a recognised specialist in electrical protection.
Key Features
- Mersen high-speed fuse technology.
- Manufacturer reference B300703.
- Designed specifically for semiconductor short-circuit protection.
- Fast operating response during severe electrical faults.
- Low fault-energy let-through for enhanced component protection.
- Suitable for industrial power conversion equipment.
- Designed for equipment-specific fuse mounting arrangements.
- Suitable for installation by qualified electrical professionals.
Reliable Protection for Power Electronics
Power semiconductor components can be permanently damaged by excessive current before a standard industrial fuse has time to operate. The Mersen B300703 is designed to interrupt short-circuit currents rapidly, helping restrict the thermal and electrical stress applied to sensitive electronic devices.
Correct fuse selection is essential for safe and dependable equipment operation. Before replacing an existing fuse, users should confirm the rated current, voltage, utilisation category, breaking capacity, dimensions, terminal configuration and applicable approvals against the original fuse or equipment documentation.
Typical Applications
- Variable frequency drives and industrial motor controllers.
- Power converters and rectifier assemblies.
- Industrial inverters and power supplies.
- Uninterruptible power supply systems.
- Renewable energy and energy storage equipment.
- Semiconductor-based automation machinery.
Technical Specifications
Tick the specs you need, then view products that match.
| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | B300703 | |
| Catalogue No | A070UD31LI500 | |
| Description | Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 500A With Striker Slotted Blades long | |
| EAN/UPC Code | 3605340332452 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 500 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 31 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 215000 A²s | |
| Melting I2t | 37000 A²s | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Indication System | Yes | |
| Indication System Type | Striker | |
| Connection/Terminal Material | Silver-Plated Copper | |
| Connection/Terminal Type | Slotted Blades | |
| Product Width | 51 mm | |
| Product Length | 148.6 mm | |
| Product Height | 56.5 mm | |
| Sell Pack Quantity | 3 EA | |
| Sell Pack Weight | 1.2519 kg | |
| Sell Pack Width | 155 mm | |
| Sell Pack Length | 165 mm | |
| Sell Pack Height | 60 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.4173 kg | |
| Power Dissipation at Rated Current Value | 72 W | |
| HS Code | 85361090 | |
| Country of Manufacture | France |
Frequently Asked Questions
What is the Mersen B300703 used for?
The Mersen B300703 is used to protect sensitive semiconductor components in industrial power electronic equipment against damaging short-circuit currents.
Which components can the B300703 protect?
High-speed semiconductor fuses are commonly used to protect IGBTs, thyristors, power diodes, rectifiers and related electronic components.
Can the B300703 be replaced with a standard industrial fuse?
A standard fuse should not be substituted unless its electrical ratings, operating speed, breaking capacity, dimensions and approvals comply with the equipment manufacturer’s requirements.
Where is this fuse commonly installed?
It may be installed in variable frequency drives, converters, inverters, UPS equipment, industrial power supplies and other semiconductor-based systems.
What should be checked before ordering the B300703?
Confirm the complete product reference, current rating, voltage rating, utilisation category, breaking capacity, physical dimensions and terminal arrangement against the existing fuse or equipment documentation.
Trusted for Industrial Electrical Protection
Mersen high-speed fuses are used by electrical engineers, machine builders and maintenance professionals to protect sensitive power electronic components in demanding industrial systems.
