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MERSEN FUSE A 070 URD 31 TTI 0350 A070URD31TTI0350
High-speed aR characteristic fuse designed for semiconductor protection with a square ceramic body, striker indication, flush UNC thread ends, rated at 350A, 690VAC IEC and 700VAC UL.
£78.23
Why Choose the Mersen D300475 Protistor® High-Speed Semiconductor Fuse?
The Mersen D300475 is a genuine Protistor® Size 31 square body high-speed semiconductor fuse designed to provide ultra-fast protection for sensitive power electronic equipment. Manufactured as an aR class semiconductor fuse, it protects diodes, thyristors, IGBTs and other semiconductor devices operating on 690 V AC (IEC) and 700 V AC (UL) systems. This model has a 350 A current rating and features an integrated striker indicator with flush-end UNC threaded terminals.
Manufactured by Mersen, Catalogue Number A070UD31TTI350, the D300475 forms part of the internationally recognised Protistor® range. It features silver-plated contact surfaces, non-magnetic hardware and precision-manufactured fuse elements embedded in solidified silica sand, providing low let-through energy and outstanding semiconductor protection.
With a 200 kA AC breaking capacity, robust ceramic square body construction and flush-end threaded connections, the D300475 is ideally suited for industrial drives, converters, UPS systems, renewable energy equipment and other demanding power conversion applications requiring rapid fault interruption.
Key Advantages
- Ultra-fast aR semiconductor protection fuse.
- 350 A rated current.
- 690 V AC IEC / 700 V AC UL voltage rating.
- Integrated striker indicator for rapid fault indication.
- Flush-end UNC threaded terminals for secure bolted installation.
- 200 kA interrupting capacity.
Key Features
- Mersen Protistor® Size 31 semiconductor fuse.
- Catalogue number: A070UD31TTI350.
- 350 A rated current.
- 690 V AC IEC / 700 V AC UL.
- aR operating class.
- Integrated striker indication.
- Flush-end UNC threaded terminals.
- Square body bolted mounting.
Engineered for High-Speed Semiconductor Protection
Protistor® semiconductor fuses are engineered to minimise fault energy during overloads and short circuits, helping to protect expensive semiconductor devices while reducing equipment downtime. Their ultra-fast operating characteristics make them ideal for industrial power conversion equipment where fast fault clearance is essential.
The Mersen D300475 combines low I²t performance, high interrupting capacity and rugged construction to provide dependable protection in industrial automation, motor drives, UPS systems, renewable energy installations and power converters.
Typical Applications
- Variable speed drives.
- Industrial power converters.
- UPS systems.
- Renewable energy inverters.
- Motor control centres.
- Semiconductor protection circuits.
Technical Specifications
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| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | D300475 | |
| Catalogue No | A070UD31TTI350 | |
| Description | Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 350A With Striker Flush ends UNC threads | |
| EAN/UPC Code | 3605340329049 | |
| Rated voltage AC UL | 700 V | |
| Rated voltage AC IEC | 690 V | |
| Ampere Rating | 350 A | |
| RoHS Compliant | Yes | |
| AC or DC | AC | |
| Speed/Characteristic | aR | |
| Fuse Size | 31 | |
| Mounting | Bolted | |
| Clearing I2t At Rated Voltage | 61000 A²s | |
| Melting I2t | 10300 A²s | |
| AC Max I.R./Breaking Capacity | I1: 200 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 | 50.6 mm | |
| Product Height | 56.5 mm | |
| Sell Pack Quantity | 3 EA | |
| Sell Pack Weight | 1.155 kg | |
| Sell Pack Width | 85 mm | |
| Sell Pack Length | 168 mm | |
| Sell Pack Height | 65 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.385 kg | |
| Power Dissipation at Rated Current Value | 67 W | |
| HS Code | 85361090 | |
| Country of Manufacture | France |
Frequently Asked Questions
What is the Mersen D300475 used for?
The D300475 provides ultra-fast protection for power semiconductor devices including IGBTs, thyristors and diodes used in industrial power conversion equipment.
What is the current rating?
The fuse has a rated current of 350 A.
What voltage systems is it designed for?
It is rated for 690 V AC (IEC) and 700 V AC (UL) installations.
Does the D300475 include a blown fuse indicator?
Yes. It incorporates an integrated striker mechanism that can operate a compatible microswitch for remote indication.
What terminal style does this fuse use?
The D300475 uses flush-end UNC threaded terminals for secure bolted installation.
Trusted Worldwide for Semiconductor Protection
Mersen Protistor® semiconductor fuses are trusted by OEM manufacturers, panel builders and industrial engineers worldwide to protect valuable power electronic equipment in demanding industrial environments.
