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MERSEN FUSE A 120 URD 71 TTI 0550 A120URD71TTI0550
High-speed semiconductor protection fuse rated 550A, 1100VAC IEC, 1200VAC UL with striker indication and flush ends with UNC threads.
£101.68
Why Choose the Mersen L301034 Protistor® High-Speed Fuse?
The Mersen L301034, catalogue number A120UD71TTI550, is a Protistor® Size 71 square body high-speed semiconductor fuse designed to provide advanced protection for modern power conversion equipment. Featuring an ultra-fast aR operating characteristic, it delivers exceptional protection for IGBTs, thyristors, diodes and other sensitive semiconductor devices against damaging short-circuit currents.
Designed for demanding industrial applications, the L301034 incorporates precision die-cut fuse elements embedded in solidified sand for controlled arc extinction, low I²t performance and high interrupting capacity. The fuse features flush ends with UNC threaded terminals (TTI), silver-plated contact surfaces, non-magnetic hardware and an integrated striker indicator for optional remote monitoring.
With a 550 A current rating, 1100 V AC IEC and 1200 V AC UL voltage ratings, the Mersen L301034 is ideally suited to industrial drives, renewable energy converters, UPS systems, traction equipment and other high-power semiconductor applications.
Key Advantages
- Ultra-fast aR semiconductor protection fuse.
- 550 A current rating for demanding industrial applications.
- 1100 V AC IEC / 1200 V AC UL voltage capability.
- Low I²t characteristics minimise semiconductor damage.
- 150 kA AC breaking capacity.
- Flush UNC threaded terminals for secure bolted installation.
- Integrated striker supports optional remote indication.
- Silver-plated contacts for reliable long-term performance.
Key Features
- Mersen Protistor® Size 71 series.
- Catalogue number: A120UD71TTI550.
- 550 A rated current.
- 1100 V AC IEC / 1200 V AC UL rated voltage.
- aR ultra-fast operating characteristic.
- Flush ends with UNC threaded terminals (TTI).
- Integrated low-voltage striker indicator.
- Silver-plated contact surfaces.
- Square body ceramic construction.
Designed for High-Power Semiconductor Protection
Protistor® semiconductor fuses are specifically engineered to interrupt extremely high fault currents before expensive semiconductor devices suffer catastrophic damage. Their ultra-fast operation and low energy let-through characteristics maximise equipment reliability while reducing maintenance costs across demanding industrial power conversion systems.
The robust square body construction, precision fuse elements, silver-plated contacts and integrated striker make the Mersen L301034 an excellent solution for protecting industrial converters, motor drives, renewable energy systems and other critical semiconductor equipment.
Typical Applications
- High-power variable speed drives.
- Industrial power converters.
- Renewable energy inverters.
- UPS systems.
- Industrial rectifiers.
- Traction power equipment.
- IGBT, thyristor and diode protection.
Technical Specifications
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| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Class | aR | |
| Voltage | 1100 V | |
| Item number | L301034 | |
| Catalogue No | A120UD71TTI550 | |
| Description | Square Body High-Speed Fuse Protistor® Size 71 aR 1100VAC IEC 1200VAC UL 550A With Striker Flush ends UNC threads | |
| EAN/UPC Code | 3605340335682 | |
| Rated voltage AC UL | 1200 V | |
| Rated voltage AC IEC | 1100 V | |
| Ampere Rating | 550 A | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 71 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 548 kA²s | |
| Melting I2t | 84 kA²s | |
| AC Max I.R./Breaking Capacity | I1: 150 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 | 1.5 kg | |
| Sell Pack Width | 85 mm | |
| Sell Pack Length | 170 mm | |
| Sell Pack Height | 70 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.5 kg | |
| Power Dissipation at Rated Current Value | 98 W | |
| HS Code | 85351000 |
Frequently Asked Questions
What is the Mersen L301034 used for?
The Mersen L301034 is an ultra-fast semiconductor protection fuse designed to protect IGBTs, thyristors, diodes and other sensitive semiconductor devices against short-circuit faults.
What is the current rating of the L301034?
The Mersen L301034 has a rated current of 550 A.
What voltage is the fuse rated for?
The fuse is rated for 1100 V AC (IEC) and 1200 V AC (UL).
What type of terminals does the L301034 use?
The fuse features flush ends with UNC threaded terminals (TTI) and an integrated striker indicator for secure installation and optional remote monitoring.
What applications is the L301034 suitable for?
It is commonly used in industrial drives, renewable energy converters, UPS systems, rectifiers and other high-power semiconductor applications.
Trusted Protection for Critical Power Electronics
Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, electrical engineers and industrial maintenance professionals for dependable protection of high-performance power electronic systems.
