Why Choose the Mersen J1028959 UltraSafe™ US221 Fuse Holder?
The Mersen J1028959, also identified as the US221, is a compact and dependable single-pole cylindrical fuse holder designed for industrial power distribution, machinery and electrical control applications. Part of the established Mersen UltraSafe™ US22 range, it accepts standard 22 × 58 mm cylindrical fuse-links and provides secure, finger-safe circuit protection.
This version is supplied without pre-breaking or auxiliary fuse-status indication, making it a straightforward solution for installations where remote monitoring is not required. Its pressure-plate terminals provide secure conductor connections, while the modular DIN rail format enables quick integration into control panels, switchboards and machine enclosures.
Designed for demanding AC and DC systems, the US221 fuse holder has a conventional thermal current rating of 125 A. The UltraSafe design supports ratings up to 800 V AC and 1000 V DC under UL specifications, while IEC applications are rated up to 690 V AC or DC.
Key Advantages
- Designed for standard 22 × 58 mm cylindrical fuse-links.
- Single-pole configuration for individual circuit protection.
- 125 A conventional thermal current rating.
- Suitable for high-voltage AC and DC electrical systems.
- Finger-safe IP20 construction, including during fuse replacement.
- Pressure-plate terminals provide secure conductor connections.
- Compact DIN rail mounting helps conserve panel space.
Key Features
- Mersen UltraSafe™ US22 series.
- Catalogue designation: US221.
- Manufacturer part number: J1028959.
- Single-pole modular fuse-holder design.
- Compatible with 22 × 58 mm cylindrical fuse-links.
- 125 A conventional free-air thermal current.
- Rated up to 800 V AC and 1000 V DC under UL specifications.
- Rated up to 690 V AC or DC under IEC specifications.
- Non-indicating version without pre-breaking.
- Pressure-plate terminal connection.
- DIN rail mounting for modular electrical panels.
- IP20 finger-safe housing.
- Optional accessories available for multi-pole assembly and remote indication.
Reliable Protection for Industrial AC and DC Circuits
The Mersen J1028959 provides a secure mounting and connection point for 22 × 58 mm cylindrical fuse-links. When fitted with an appropriately selected fuse, it helps protect industrial equipment against damaging overload and short-circuit currents.
Its high AC and DC voltage capability makes it suitable for power distribution, motor control, conversion equipment and renewable energy systems. The enclosed IP20 design also helps reduce accidental contact with live components during operation and routine fuse replacement.
Typical Applications
- Industrial control panels and switchboards.
- Variable speed drives and motor-control systems.
- Industrial machinery and OEM equipment.
- Power conversion and inverter systems.
- Battery and DC distribution circuits.
- Renewable energy installations.
- Commercial and industrial power distribution.
- Electrical automation equipment.
