High-speed semiconductor protection fuse with aR characteristic, rated 160A at 1250VAC IEC / 1300VAC UL, featuring a ceramic body, built-in striker indication, flush ends with metric threads, and bolted mounting.
£114.73
The Mersen B300749 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 equipment containing IGBTs, thyristors, power diodes, rectifiers and other semiconductor devices that require rapid and dependable fault interruption.
High-speed fuses operate significantly faster than conventional industrial fuses, helping limit the peak current and electrical energy that reaches protected components during a fault. This rapid response can reduce thermal stress, minimise equipment damage and improve the operational reliability of demanding power conversion systems.
The B300749 is intended for professional maintenance, replacement and machine-building applications where the fuse must be matched precisely to the original equipment requirements. It is suitable for industrial drives, converters, inverters, uninterruptible power supplies and other semiconductor-based systems requiring specialised short-circuit protection.
Power semiconductor devices can be permanently damaged by high fault currents before a standard industrial fuse has time to operate. The Mersen B300749 is designed to interrupt short-circuit currents rapidly, helping restrict the thermal and electrical stress applied to sensitive electronic components.
Correct fuse selection is essential for safe and reliable equipment operation. Before ordering or installing the B300749, confirm its current rating, voltage rating, utilisation category, breaking capacity, dimensions, terminal configuration and applicable approvals against the original fuse or equipment documentation.
| Item number | B300749 |
|---|---|
| Catalogue No | PC71UD13C160TF |
| Description | Square Body High-Speed Fuse Protistor® Size 71 aR 1250VAC IEC 1300VAC UL 160A With Striker Flush ends metric threads |
| EAN/UPC Code | 3605340332971 |
| Rated voltage AC UL | 1300 V |
| Rated voltage AC IEC | 1250 V |
| Ampere Rating | 160 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 71 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 21 kA²s |
| Melting I2t | 2.6 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 | 46 W |
| HS Code | 85351000 |
The Mersen B300749 is used to protect sensitive semiconductor components in industrial power electronic equipment against damaging short-circuit currents.
High-speed semiconductor fuses are commonly used to protect IGBTs, thyristors, power diodes, rectifiers and related electronic components.
A standard fuse should not be substituted unless its electrical ratings, operating speed, breaking capacity, dimensions and approvals comply fully with the equipment manufacturer’s requirements.
It may be installed in variable frequency drives, converters, inverters, UPS equipment, industrial power supplies and other semiconductor-based systems.
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.
Mersen high-speed fuses are used by electrical engineers, equipment manufacturers and maintenance professionals to protect sensitive power electronic components in demanding industrial 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...
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...