High-speed fuse with aR characteristic rated at 800A for AC applications up to 1100VAC IEC and 1200VAC UL, featuring a striker indication system and DIN 110 blade terminals.
£298.36
The Mersen J300572 is a premium Protistor® Size 73 aR square body high-speed semiconductor fuse engineered to provide exceptional protection for modern power electronic equipment. Designed specifically for safeguarding sensitive semiconductor devices, it delivers ultra-fast fault interruption and outstanding current limiting to protect IGBTs, thyristors, diodes and rectifiers from damaging short-circuit currents.
Manufactured by Mersen, this fuse forms part of the internationally recognised Protistor® semiconductor protection range. Its advanced construction incorporates silver-plated contact surfaces, solidified sand technology for controlled arc performance and an integrated striker for remote fuse indication, ensuring dependable operation in demanding industrial environments.
Rated at 800 A with a 1100 V AC IEC / 1200 V AC UL voltage rating, the J300572 is ideally suited to industrial drives, converters, inverters, UPS systems, renewable energy installations and other high-power semiconductor applications requiring reliable circuit protection.
High-speed semiconductor fuses are specifically engineered to interrupt severe fault currents before excessive thermal or electrical energy can damage valuable semiconductor devices. Their low let-through energy helps improve equipment reliability while reducing maintenance costs and unplanned downtime.
The Mersen Protistor® Size 73 range is trusted worldwide by OEMs, panel builders and industrial engineers for demanding power conversion applications where dependable semiconductor protection is essential.
| Current | 11 A |
|---|---|
| Item number | J300572 |
| Catalogue No | PC73UD11C800D1A |
| Description | Square Body High-Speed Fuse Protistor® Size 73 aR 1100VAC IEC 1200VAC UL 800A With Striker DIN 110 Blades |
| EAN/UPC Code | 3605340330489 |
| Rated voltage AC UL | 1200 V |
| Rated voltage AC IEC | 1100 V |
| Ampere Rating | 800 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 73 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 1230 kA²s |
| Melting I2t | 190 kA²s |
| AC Max I.R./Breaking Capacity | I1: 150 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Copper |
| Connection/Terminal Type | DIN 110 Blades |
| Product Width | 73 mm |
| Product Length | 133.4 mm |
| Product Height | 78.5 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 3.36 kg |
| Sell Pack Width | 150 mm |
| Sell Pack Length | 250 mm |
| Sell Pack Height | 90 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 1.12 kg |
| Power Dissipation at Rated Current Value | 148 W |
| HS Code | 85351000 |
The J300572 is designed to protect power semiconductor devices such as IGBTs, thyristors and rectifiers from damaging short-circuit currents.
The fuse has a rated current of 800 A for high-power industrial applications.
It is rated for 1100 V AC (IEC) and 1200 V AC (UL) systems.
The aR operating characteristic provides ultra-fast short-circuit protection specifically for semiconductor devices without providing overload protection.
It is typically installed in industrial drives, converters, UPS systems, renewable energy equipment and other high-power semiconductor applications.
Mersen Protistor® semiconductor fuses are trusted worldwide for delivering dependable, ultra-fast protection for industrial power electronics, helping maximise equipment availability and protect valuable semiconductor devices.
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LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.
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...