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MERSEN FUSE A 070 URD 33 KI 0550 A070URD33KI0550
High-speed aR characteristic fuse designed for semiconductor protection with 550A rating and 700VAC UL / 690VAC IEC voltage ratings. Features integrated striker indication and silver-plated copper slotted blade terminals.
£111.27
Why Choose the Mersen X300239 Protistor® High-Speed Fuse?
The Mersen X300239 is a premium square body semiconductor protection fuse designed to provide ultra-fast protection for power semiconductor devices including IGBTs, thyristors and diodes. Part of the trusted Mersen Protistor® Size 33 aR series, it delivers reliable fault protection for demanding industrial power conversion and automation applications.
Designed for high interrupting performance and low energy let-through, the X300239 helps protect expensive semiconductor components from short-circuit faults while improving the reliability and service life of power electronic equipment. Its robust square body construction and silver-plated contacts ensure dependable operation in demanding industrial environments.
With a 550 A current rating and a 700 V AC operating voltage, the Mersen X300239 is ideally suited for protecting industrial drives, UPS systems, converters, renewable energy inverters and other high-power electronic equipment requiring fast semiconductor protection.
Key Advantages
- Ultra-fast aR semiconductor protection fuse.
- 550 A current rating for industrial power electronics.
- 700 V AC voltage rating.
- High interrupting capacity for critical fault protection.
- Optimised for protecting IGBTs, diodes and thyristors.
- Reliable square body construction for demanding industrial applications.
Key Features
- Mersen Protistor® Size 33 series.
- 550 A rated current.
- 700 V AC rated voltage.
- aR ultra-fast operating characteristic.
- Square body bolted construction.
- Silver-plated contact surfaces.
- Low energy let-through protection.
- Designed for semiconductor device protection.
Reliable Semiconductor Protection
High-speed semiconductor fuses are specifically engineered to interrupt high fault currents before damage can occur to sensitive semiconductor devices. Their ultra-fast response helps reduce thermal stress while improving the reliability and availability of industrial power conversion systems.
The Mersen Protistor® range is widely used throughout industrial automation, renewable energy, motor control and power conversion industries where dependable semiconductor protection is essential for maintaining system uptime.
Typical Applications
- Variable frequency drives (VFDs).
- Industrial motor drives.
- UPS systems.
- Power converters and rectifiers.
- Renewable energy inverters.
- Industrial automation and power electronics.
Technical Specifications
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| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | X300239 | |
| Catalogue No | A070UD33KI550 | |
| Description | Square Body High-Speed Fuse Protistor® Size 33 aR 690VAC IEC 700VAC UL 550A With Striker Slotted Blades short | |
| EAN/UPC Code | 3605340325515 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 550 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 33 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 155 kA²s | |
| Melting I2t | 27 kA²s | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Design Details | Standard Terminal | |
| Indication System | Yes | |
| Indication System Type | Striker | |
| Connection/Terminal Material | Silver-Plated Copper | |
| Connection/Terminal Type | Slotted Blades | |
| Product Width | 73 mm | |
| Product Length | 134 mm | |
| Product Height | 78.5 mm | |
| Sell Pack Quantity | 3 EA | |
| Sell Pack Weight | 2.5353 kg | |
| Sell Pack Width | 145 mm | |
| Sell Pack Length | 245 mm | |
| Sell Pack Height | 90 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.8451 kg | |
| Power Dissipation at Rated Current Value | 110 W | |
| HS Code | 85361090 |
Frequently Asked Questions
What is the Mersen X300239 used for?
The X300239 provides ultra-fast protection for semiconductor devices such as IGBTs, diodes and thyristors used in industrial power electronic equipment.
What is the current rating of the X300239?
This fuse has a 550 A current rating.
What voltage is the fuse rated for?
The Mersen X300239 is rated for 700 V AC.
What type of fuse is the X300239?
It is an aR ultra-fast semiconductor protection fuse designed specifically for protecting power semiconductor devices against short-circuit faults.
Where is this fuse typically installed?
It is commonly installed in variable speed drives, converters, UPS systems, renewable energy equipment and industrial power electronic systems.
Trusted Protection for Industrial Power Electronics
Mersen Protistor® semiconductor fuses are trusted worldwide to deliver dependable protection for high-value power electronic equipment, helping maximise equipment reliability and minimise downtime.
