High-speed aR fuse with 550A rating, integrated striker indication, ceramic body, and plain blade terminals for semiconductor protection in industrial applications.
£266.23
The Mersen Y302977 (PC73UD13C550PA) is a premium square body high-speed semiconductor fuse designed to provide exceptional protection for sensitive power electronic devices. Part of the trusted Mersen Protistor® Size 73 series, this ultra-fast acting aR fuse safeguards semiconductors including IGBTs, thyristors and diodes used in demanding industrial power conversion applications.
Engineered for reliability and maximum equipment uptime, the Y302977 delivers outstanding current limitation and low let-through energy, helping minimise damage during fault conditions. Its robust square body construction, silver-plated contacts and integrated striker make it ideal for modern industrial power systems requiring dependable semiconductor protection.
Rated at 550 A with a 1250 V AC IEC / 1300 V AC UL voltage rating, the Mersen Y302977 is suitable for use in converters, UPS systems, motor drives, renewable energy installations and other high-power industrial applications where fast fault interruption is essential.
High-speed semiconductor fuses are specifically engineered to protect sensitive electronic power devices from damaging short circuits. Unlike conventional industrial fuses, Protistor® fuses rapidly interrupt fault currents with extremely low let-through energy, significantly reducing the risk of costly damage to semiconductor components.
The Mersen Protistor® Size 73 range is widely specified for industrial drives, converters, UPS equipment, renewable energy systems and heavy-duty power conversion equipment where reliable semiconductor protection is essential for maintaining operational continuity.
| Item number | Y302977 |
|---|---|
| Catalogue No | PC73UD13C550PA |
| Description | Square Body High-Speed Fuse Protistor® Size 73 aR 1250VAC IEC 1300VAC UL 550A With Striker Plain Blades |
| EAN/UPC Code | 3605340379877 |
| Rated voltage AC UL | 1300 V |
| Rated voltage AC IEC | 1250 V |
| Ampere Rating | 550 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 73 |
| Mounting | Clip |
| Clearing I2t At Rated Voltage | 465 kA²s |
| Melting I2t | 57 kA²s |
| AC Max I.R./Breaking Capacity | I1: 126 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Copper |
| Connection/Terminal Type | Plain Blades |
| Product Width | 73 mm |
| Product Length | 149.4 mm |
| Product Height | 78.5 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 3.48 kg |
| Sell Pack Width | 160 mm |
| Sell Pack Length | 245 mm |
| Sell Pack Height | 100 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 1.16 kg |
| Power Dissipation at Rated Current Value | 120 W |
| HS Code | 85351000 |
The Y302977 is a high-speed semiconductor fuse designed to protect IGBTs, thyristors, diodes and other power semiconductor devices against short circuit faults.
This fuse has a 550 A continuous current rating.
The fuse is rated for 1250 V AC (IEC) and 1300 V AC (UL).
The aR characteristic provides ultra-fast protection for semiconductor devices against short circuits while allowing equipment designers to use separate overload protection where required.
The built-in striker provides mechanical indication of fuse operation and can be used to activate auxiliary microswitches for remote monitoring.
Mersen Protistor® semiconductor fuses are trusted worldwide by engineers and equipment manufacturers for protecting valuable power electronics in industrial automation, energy and power conversion systems.
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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...