High-speed Protistor® fuse with aR characteristic, 1100A rating, 900VAC IEC and 1000VAC UL voltage ratings, featuring striker indication and slotted blade terminals for secure bolted mounting.
£342.43
The Mersen N300691, also identified by catalogue number A100UD73LI1100, is a premium Protistor® square body high-speed semiconductor fuse engineered to provide exceptional protection for sensitive power electronic devices. Designed for demanding industrial applications, this ultra-fast acting fuse helps safeguard semiconductor components such as diodes, thyristors and IGBT modules against short circuits and overcurrent faults.
As part of the renowned Mersen Protistor® Size 73 series, the N300691 delivers outstanding current-limiting performance while reducing the risk of costly equipment damage and downtime. Its robust square body construction, silver-plated contacts and high breaking capacity make it an ideal choice for modern power conversion systems and industrial automation equipment.
Rated at 1100 A with a 900 V AC IEC / 1000 V AC UL voltage rating, the Mersen N300691 is suitable for protecting high-power converters, motor drives, UPS systems and renewable energy installations where dependable semiconductor protection is essential.
High-speed semiconductor fuses are specifically designed to protect sensitive electronic power devices by interrupting excessive fault currents before permanent damage can occur. The Mersen Protistor® range combines rapid operation with low let-through energy, helping extend the service life of expensive industrial equipment.
The N300691 is widely used in power conversion systems where reliable protection is critical. Its advanced construction provides dependable performance in demanding industrial environments while supporting high equipment availability and reduced maintenance requirements.
| Item number | N300691 |
|---|---|
| Catalogue No | A100UD73LI1100 |
| Description | Square Body High-Speed Fuse Protistor® Size 73 aR 900VAC IEC 1000VAC UL 1100A With Striker Slotted Blades long |
| EAN/UPC Code | 3605340560039 |
| Rated voltage AC UL | 1000 V |
| Rated voltage AC IEC | 900 V |
| Ampere Rating | 1100 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 73 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 2280 kA²s |
| Melting I2t | 445 kA²s |
| AC Max I.R./Breaking Capacity | I1: 151 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Copper |
| Connection/Terminal Type | Slotted Blades |
| Product Width | 73 mm |
| Product Length | 157.4 mm |
| Product Height | 78.5 mm |
| Sell Pack Quantity | 1 EA |
| Sell Pack Weight | 1.25 kg |
| Sell Pack Width | 100 mm |
| Sell Pack Length | 180 mm |
| Sell Pack Height | 80 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 1.25 kg |
| Power Dissipation at Rated Current Value | 208 W |
| HS Code | 85361090 |
The N300691 is designed to protect semiconductor devices such as IGBTs, thyristors and diodes in industrial power conversion equipment.
This high-speed fuse has a 1100 A current rating.
The fuse is rated for 900 V AC (IEC) and 1000 V AC (UL) applications.
It is a Protistor® Size 73 square body ultra-fast acting aR semiconductor protection fuse with striker indication.
It is commonly installed in industrial drives, power converters, UPS systems and other equipment requiring high-speed semiconductor protection.
Mersen Protistor® semiconductor fuses are trusted across industrial automation, renewable energy and power conversion industries for delivering dependable high-speed protection for valuable electronic equipment.
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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...