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MERSEN FUSE 30A J 3P ULTRASAFE W/IND US3J3I
Mersen US3J3I UltraSafe three-pole Class J fuse holder rated 30 A and 600 V AC/DC with LED blown-fuse indicators, 200 kA SCCR, IP20 finger-safe protection and DIN rail mounting.
£94.06
Why Choose the Mersen US3J3I UltraSafe™ Class J Fuse Holder?
The Mersen US3J3I is a high-performance three-pole UltraSafe™ Class J fuse holder designed to provide dependable overcurrent protection for three-phase industrial electrical systems. It accommodates Class J fuses rated up to 30 A and combines compact DIN rail mounting with robust finger-safe construction for straightforward installation inside control panels, switchboards and power distribution equipment.
The US3J3I incorporates an LED blown-fuse indicator in each pole, allowing maintenance personnel to identify an operated fuse quickly without removing the fuse links for inspection. This clear visual indication helps reduce fault-finding time, minimise equipment downtime and simplify maintenance in industrial machinery and automation systems.
Rated for 30 A with 600 V AC and 600 V DC operation, the US3J3I provides a 200 kA short-circuit current rating when correctly applied with approved Class J fuses. Its pressure-plate terminals, clip-in fuse installation and lockable open position make it a safe and practical solution for demanding three-phase applications.
Key Advantages
- Compact three-pole Class J fuse holder for three-phase industrial systems.
- Integrated LED blown-fuse indicator in each pole.
- Compatible with Class J fuses rated up to 30 A.
- 600 V AC / 600 V DC rated operation.
- 200 kA short-circuit current rating for demanding electrical applications.
- IP20 finger-safe construction improves protection during operation and maintenance.
Key Features
- Mersen UltraSafe™ US3J series.
- Three-pole modular fuse holder.
- 30 A maximum fuse rating.
- 600 V AC UL rated voltage.
- 600 V DC UL rated voltage.
- Integrated LED blown-fuse indication.
- Compatible with Mersen AJT, A4J and HSJ Class J fuses.
- Accepts compatible 22 × 58 mm ferrule fuse links in non-UL applications.
- Pressure-plate terminals with clip-in fuse installation.
- 35 mm DIN rail mounting with a lockable open position.
Visible Fuse Status for Three-Phase Power Systems
The Mersen US3J3I securely houses three Class J fuses and provides reliable overcurrent protection for three-phase industrial circuits. Its finger-safe housing helps reduce the risk of accidental contact with live components, whilst the lockable open position supports safer fuse replacement and electrical maintenance.
An LED indicator is incorporated into each pole to provide immediate visual notification when a fuse has operated. This allows engineers to locate the affected phase quickly, helping restore machinery and electrical equipment to service with less diagnostic work and reduced production interruption.
Typical Applications
- Three-phase industrial control panels.
- Motor and transformer protection circuits.
- Power distribution systems and switchboards.
- Heating and industrial lighting equipment.
- OEM machinery and production equipment.
- Industrial automation and process control systems.
Technical Specifications
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| Fuse Indication | Visual indicator | |
|---|---|---|
| Current | 30 A | |
| Phase | Three Phase | |
| Poles | 3-pole | |
| Device Type | Fuse base / holder | |
| Fuse Type | UL class | |
| Fuse Size | 22x58 mm | |
| Voltage | 600 V | |
| Manufacturer | Mersen | |
| Series | UltraSafe™ US3J | |
| Model | US3J3I | |
| Product type | Class J modular fuse holder | |
| Fuse class | Class J | |
| Number of poles | 3 | |
| Maximum fuse rating | 30 A | |
| Rated voltage AC | 600 V UL | |
| Rated voltage DC | 600 V UL | |
| Frequency | 50 / 60 Hz | |
| Short-circuit current rating | 200 kA | |
| Indication system | LED blown-fuse indicator in each pole | |
| Compatible fuse references | AJT, A4J and HSJ | |
| Alternative fuse size | 22 × 58 mm ferrule fuse link | |
| Conductor range | 2 to 14 AWG copper | |
| Terminal type | Pressure plate | |
| Terminal torque | 35 lb-in | |
| Fuse installation | Clip-in | |
| Protection rating | IP20 finger-safe | |
| Mounting type | 35 mm DIN rail | |
| Approximate dimensions (W × D × H) | 99 × 119 × 82 mm | |
| Standards | UL Listed, CSA certified and IEC compliant | |
| HS Code | 85369095 | |
| Country of Manufacture | China |
Frequently Asked Questions
What is the Mersen US3J3I used for?
The US3J3I is a three-pole UltraSafe™ fuse holder used to install and protect Class J fuses rated up to 30 A in three-phase industrial AC and DC electrical systems.
Does the US3J3I include blown-fuse indication?
Yes. It includes an integrated LED blown-fuse indicator in each pole, allowing the affected phase to be identified quickly.
Which fuses are compatible with the US3J3I?
The holder is designed for Mersen AJT, A4J and HSJ Class J fuses rated up to 30 A. Compatible 22 × 58 mm ferrule fuse links may also be used in non-UL applications.
What are the voltage and current ratings?
The US3J3I is rated for a maximum of 30 A with operating voltages up to 600 V AC or 600 V DC.
How is the Mersen US3J3I installed?
It is designed to mount onto a standard 35 mm DIN rail and uses pressure-plate terminals for secure conductor connections.
Trusted by Industrial Engineers Worldwide
Mersen UltraSafe™ Class J fuse holders are widely specified by OEMs, panel builders and industrial engineers for dependable overcurrent protection, visible fuse-status indication and safer maintenance of industrial electrical systems.
