High-speed fuse with 500A rating, flush ends, striker indication, and metric threads for bolted mounting. Certified IEC 1100VAC and UL 1200VAC.
£170.45
The Mersen F300523 is a specialist high-speed semiconductor protection fuse designed to protect sensitive power electronic components against damaging short-circuit currents. Developed for demanding industrial electrical systems, it provides the rapid fault interruption required by equipment containing semiconductor devices such as IGBTs, thyristors, diodes and rectifier modules.
As part of Mersen’s established Protistor® semiconductor fuse range, the F300523 is engineered to deliver low let-through energy and dependable current limitation. These characteristics help reduce thermal and electrical stress on valuable power electronics, supporting improved equipment reliability and reduced unplanned downtime.
The F300523 is suitable for industrial motor drives, power converters, inverters, uninterruptible power supplies and automation systems. Its robust construction makes it an effective replacement component for applications requiring fast-acting semiconductor protection. The fuse rating, terminal arrangement and physical dimensions should be checked against the equipment documentation before installation.
Semiconductor devices can suffer permanent damage within milliseconds when exposed to excessive fault current. High-speed fuses such as the Mersen F300523 are designed to operate significantly faster than conventional general-purpose fuse links, limiting the energy that reaches the protected components.
Correct fuse coordination helps protect critical equipment while supporting safe and reliable system operation. Before fitting the F300523, engineers should verify the required current rating, voltage rating, breaking capacity, fuse class, terminal configuration and physical dimensions against the original equipment specifications.
| Item number | F300523 |
|---|---|
| Catalogue No | PC71UD11C500TF |
| Description | Square Body High-Speed Fuse Protistor® Size 71 aR 1100VAC IEC 1200VAC UL 500A With Striker Flush ends metric threads |
| EAN/UPC Code | 3605340329759 |
| Rated voltage AC UL | 1200 V |
| Rated voltage AC IEC | 1100 V |
| Ampere Rating | 500 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 71 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 441 kA²s |
| Melting I2t | 68 kA²s |
| AC Max I.R./Breaking Capacity | I1: 150 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 | 74 mm |
| Product Height | 56.5 mm |
| Sell Pack Quantity | 3 EA |
| Sell Pack Weight | 1.545 kg |
| Sell Pack Width | 90 mm |
| Sell Pack Length | 170 mm |
| Sell Pack Height | 70 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 0.515 kg |
| Power Dissipation at Rated Current Value | 90 W |
| HS Code | 85351000 |
The Mersen F300523 is used to protect sensitive semiconductor devices and industrial power electronic equipment against damaging short-circuit currents.
It is suitable for equipment containing IGBTs, thyristors, diodes, rectifiers and power semiconductor modules.
No. It is a specialist high-speed fuse intended primarily for semiconductor and power electronic protection rather than general cable overload protection.
It may be used in variable frequency drives, converters, inverters, UPS systems, soft starters and other industrial power electronic equipment.
The current rating, voltage rating, breaking capacity, fuse characteristic, dimensions and terminal arrangement should be checked against the equipment manufacturer’s requirements.
Mersen high-speed fuses are used by electrical engineers, machine builders and maintenance professionals to protect valuable semiconductor equipment and support dependable operation in demanding industrial power systems.
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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...