High-speed aR characteristic fuse designed for semiconductor protection in industrial power electronics applications, rated at 315A, 1250VAC IEC, 1300VAC UL, with integrated striker and bolted mounting.
£187.84
The Mersen J300503 is a high-speed semiconductor protection fuse designed to protect sensitive power electronic components against damaging short-circuit currents. As part of Mersen’s established Protistor® fuse range, it provides rapid fault interruption and effective current limitation for demanding industrial power conversion applications.
This specialist fuse helps protect components such as IGBTs, thyristors, rectifiers and power diodes by limiting the thermal and electrical energy released during a fault. Its fast operating characteristics can reduce equipment damage, improve system reliability and minimise costly production downtime.
The Mersen J300503 is suited to industrial drives, converters, inverters, uninterruptible power supplies and other equipment containing high-value semiconductor devices. Its robust construction supports dependable performance in control panels, power distribution assemblies and OEM electrical systems.
High-speed semiconductor fuses operate more rapidly than conventional general-purpose fuses. They are engineered to interrupt severe fault currents before excessive electrical or thermal energy reaches vulnerable semiconductor components.
The Mersen Protistor® range is widely specified for power electronic equipment where dependable short-circuit protection is essential. Correct fuse selection helps extend equipment service life, reduce maintenance requirements and improve the operational availability of industrial machinery.
| Item number | J300503 |
|---|---|
| Catalogue No | PC73UD13C315TF |
| Description | Square Body High-Speed Fuse Protistor® Size 73 aR 1250VAC IEC 1300VAC UL 315A With Striker Flush ends metric threads |
| EAN/UPC Code | 3605340329421 |
| Rated voltage AC UL | 1300 V |
| Rated voltage AC IEC | 1250 V |
| Ampere Rating | 315 A |
| AC or DC | AC |
| Speed/Characteristic | aR |
| Fuse Size | 73 |
| Mounting | Bolted |
| Clearing I2t At Rated Voltage | 95 kA²s |
| Melting I2t | 12 kA²s |
| AC Max I.R./Breaking Capacity | I1: 126 kA |
| Indication System | Yes |
| Indication System Type | Striker |
| Connection/Terminal Material | Silver-Plated Brass |
| Connection/Terminal Type | Flush ends |
| Product Width | 73 mm |
| Product Length | 74 mm |
| Product Height | 78.5 mm |
| Sell Pack Quantity | 1 EA |
| Sell Pack Weight | 1.22 kg |
| Sell Pack Width | 110 mm |
| Sell Pack Length | 125 mm |
| Sell Pack Height | 75 mm |
| Product group | Semiconductor Protection Fuses |
| Body/Insulating Material | Ceramic |
| Product Weight | 1.22 kg |
| Power Dissipation at Rated Current Value | 84 W |
| HS Code | 85351000 |
The Mersen J300503 is used to provide high-speed short-circuit protection for semiconductor devices installed in industrial power electronic equipment.
It is designed for applications containing sensitive components such as IGBTs, thyristors, rectifiers and power diodes.
A high-speed fuse interrupts fault currents rapidly and limits the energy reaching sensitive semiconductor components, helping reduce the risk of extensive equipment damage.
It may be installed in drives, converters, inverters, UPS systems, industrial power supplies and other power conversion equipment.
Semiconductor fuses have specialist operating characteristics and should only be used where their electrical ratings, dimensions and mounting arrangement match the equipment manufacturer’s requirements.
Mersen Protistor® high-speed fuses are trusted in industrial power electronic systems where rapid fault interruption, effective current limitation and dependable semiconductor protection are essential.
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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...