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MERSEN FUSE A 070 URD 31 KI 0350 A070URD31KI0350
High-speed aR fuse with 350A rating, ceramic body, striker indication system, slotted silver-plated copper blades, rated for 690VAC IEC and 700VAC UL standards.
£84.53
Why Choose the Mersen R300050 Protistor® High-Speed Fuse?
The Mersen R300050 (A070UD31KI350) is a premium Protistor® Size 31 square body high-speed semiconductor fuse designed to provide ultra-fast protection for modern power conversion equipment. Featuring an aR ultra-fast operating characteristic, it is specifically engineered to protect diodes, thyristors, IGBTs and other semiconductor devices against damaging short-circuit currents.
Constructed using precision die-cut silver fuse elements embedded in solidified sand, the R300050 delivers exceptional current limitation, low let-through energy and a high interrupting capacity. Silver-plated contacts, non-magnetic hardware and an integrated striker indicator provide dependable long-term performance while simplifying maintenance and remote monitoring.
With a 350 A current rating, 690 V AC (IEC) and 700 V AC (UL) voltage ratings, this Protistor® fuse is ideally suited to industrial drives, UPS systems, power converters, renewable energy installations and other demanding semiconductor applications.
Key Advantages
- Ultra-fast aR semiconductor protection fuse.
- 350 A current rating.
- 690 V AC IEC / 700 V AC UL voltage rating.
- Excellent current-limiting performance with low I²t values.
- Integrated striker indicator for simplified maintenance.
- Designed specifically for protecting IGBTs, thyristors and diode modules.
Key Features
- Mersen Protistor® Size 31 series.
- Catalogue number: A070UD31KI350.
- aR ultra-fast operating characteristic.
- 350 A rated current.
- 690 V AC (IEC) / 700 V AC (UL).
- Short slotted blade terminals.
- Integrated striker indicator.
- Ceramic square body with silver-plated contact surfaces.
Reliable Protection for Power Electronics
Protistor® semiconductor fuses are specifically developed to interrupt fault currents before expensive semiconductor devices can be damaged. Their exceptionally fast response and low let-through energy help improve equipment reliability, minimise maintenance costs and reduce costly production downtime.
The Size 31 Protistor® range is widely used throughout industrial automation, renewable energy systems, motor drives, UPS installations and power conversion equipment where dependable semiconductor protection is essential.
Typical Applications
- Variable speed drives (VSDs).
- Industrial motor control systems.
- Power converters and inverters.
- Industrial rectifiers.
- UPS systems.
- Renewable energy power conversion equipment.
- Protection of IGBTs, thyristors and diode modules.
Technical Specifications
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| Fuse Indication | Striker | |
|---|---|---|
| Fuse Type | Semiconductor | |
| Fuse Class | aR | |
| Voltage | 690 V | |
| Item number | R300050 | |
| Catalogue No | A070UD31KI350 | |
| Description | Square Body High-Speed Fuse Protistor® Size 31 aR 690VAC IEC 700VAC UL 350A With Striker Slotted Blades short | |
| EAN/UPC Code | 3605340322743 | |
| 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 Copper | |
| Connection/Terminal Type | Slotted Blades | |
| Product Width | 51 mm | |
| Product Length | 129 mm | |
| Product Height | 56.5 mm | |
| Sell Pack Quantity | 3 EA | |
| Sell Pack Weight | 1.203 kg | |
| Sell Pack Width | 157 mm | |
| Sell Pack Length | 166 mm | |
| Sell Pack Height | 62 mm | |
| Product group | Semiconductor Protection Fuses | |
| Body/Insulating Material | Ceramic | |
| Product Weight | 0.401 kg | |
| Power Dissipation at Rated Current Value | 67 W | |
| HS Code | 85361090 | |
| Country of Manufacture | France |
Frequently Asked Questions
What is the Mersen R300050 used for?
The Mersen R300050 provides ultra-fast short-circuit protection for semiconductor devices including IGBTs, thyristors, diodes and other power electronic components.
What is the current rating?
The R300050 has a rated current of 350 A.
What voltage is the fuse rated for?
It is rated at 690 V AC (IEC) and 700 V AC (UL).
What does the aR operating characteristic mean?
The aR classification identifies an ultra-fast semiconductor protection fuse intended to clear short-circuit faults while protecting sensitive semiconductor devices.
Does the fuse include a status indicator?
Yes. The R300050 incorporates an integrated striker indicator that can operate an optional field-mountable microswitch for remote indication.
Trusted Protection for Critical Industrial Systems
Mersen Protistor® semiconductor fuses are trusted worldwide by OEMs, panel builders and industrial engineers to provide dependable protection for critical power electronic equipment operating in demanding industrial environments.
