Why Choose the Mersen US3J1I UltraSafe™ Class J Fuse Holder?
The Mersen US3J1I is a high-performance single-pole UltraSafe™ Class J fuse holder designed to provide safe and dependable overcurrent protection in industrial electrical systems. It accommodates 30 A Class J fuses and combines compact DIN rail mounting with a durable finger-safe housing for straightforward installation inside control panels and distribution equipment.
Unlike the standard US3J1 version, the US3J1I includes an integrated LED blown-fuse indicator. This allows maintenance personnel to identify an operated fuse quickly, helping reduce fault-finding time and minimise disruption to machinery, production equipment and essential electrical systems.
Rated for 30 A with 600 V AC and 600 V DC operation, the US3J1I provides a 200 kA short-circuit current rating when correctly applied. It can also accommodate compatible 22 × 58 mm ferrule fuse links, although the holder is not UL Listed when used with these alternative fuse links.
Key Advantages
- Compact single-pole Class J fuse holder for industrial systems.
- Integrated LED blown-fuse indicator simplifies fault identification.
- Compatible with 30 A Class J fuses.
- 600 V AC / 600 V DC rated operation.
- 200 kA short-circuit current rating for demanding applications.
- IP20 finger-safe construction improves operator protection.
Key Features
- Mersen UltraSafe™ US3J series.
- Single-pole fuse holder.
- 30 A maximum fuse rating.
- 600 V AC UL rated voltage.
- 600 V DC UL rated voltage.
- Integrated LED indication system.
- Compatible with AJT, A4J and HSJ Class J fuses.
- Pressure-plate terminals for secure conductor connections.
- Clip-in fuse installation method.
- 35 mm DIN rail mounting with lockable open position.
Visible Fuse Status for Industrial Power Systems
The Mersen US3J1I securely houses a Class J fuse while providing a convenient means of isolating and replacing the fuse during maintenance. Its lockable open position helps improve safety during servicing, while the clip-in installation method enables quick fuse replacement without removing the holder from the DIN rail.
The integrated LED indicator provides a clear visual signal when the installed fuse has operated. This makes the US3J1I particularly useful in industrial control panels and machinery where rapid fault identification, reduced maintenance time and reliable system protection are important.
Typical Applications
- Industrial control panels.
- Motor and transformer protection.
- Power distribution systems.
- Heating and lighting circuits.
- OEM machinery and automation equipment.
- General industrial electrical loads.