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MERSEN FUSE US143I US143I
Mersen P331144 UltraSafe US143I modular fuse holder for 14×51 mm cylindrical fuse links with 3-pole configuration, visual blown fuse indicator, 50 A rating and IP20 finger-safe protection.
£53.56
Why Choose the Mersen P331144 UltraSafe™ US143I Fuse Holder?
The Mersen P331144, catalogue reference US143I, is a premium UltraSafe™ modular fuse holder designed for 14×51 mm cylindrical fuse links. Its 3-pole configuration and integrated visual blown fuse indicator provide dependable overcurrent protection whilst enabling rapid local identification of an operated fuse in industrial electrical systems.
Part of the trusted Mersen UltraSafe™ US14 series, the US143I features a robust thermoplastic construction with IP20 finger-safe protection, including during fuse replacement. The modular design allows quick DIN rail installation and can be field assembled with compatible accessories to create multi-pole arrangements where required.
Rated at 50 A with voltage ratings up to 800 V AC UL, 750 V AC IEC and 1000 V DC UL, the P331144 is ideal for industrial control panels, OEM machinery, motor control centres and electrical distribution equipment requiring reliable circuit protection and clear fuse indication.
Key Advantages
- Designed for 14×51 mm cylindrical fuse links.
- 3-pole modular construction.
- Integrated visual blown fuse indicator.
- 50 A current rating.
- Rated up to 800 V AC UL, 750 V AC IEC and 1000 V DC UL.
- Finger-safe IP20 protection.
- Pressure-plate terminals provide secure conductor retention.
- DIN rail mounting for straightforward installation.
- Compatible with field assembly pin-tie kits.
Key Features
- Mersen UltraSafe™ US14 series.
- Catalogue number US143I.
- Manufacturer part number P331144.
- Suitable for 14×51 mm cylindrical fuse links.
- 3-pole configuration.
- Integrated visual blown fuse indicator.
- 50 A conventional free-air thermal current.
- 800 V AC UL / 750 V AC IEC / 1000 V DC UL ratings.
- Pressure-plate terminals.
- IP20 finger-safe enclosure.
- DIN rail mounting.
- Compatible with optional auxiliary microswitch accessories.
Reliable Industrial Circuit Protection
The Mersen P331144 combines dependable overcurrent protection with an integrated visual indication system that enables maintenance personnel to quickly identify an operated fuse without removing the fuse holder. This helps reduce downtime and simplifies troubleshooting in industrial installations.
Its UltraSafe™ finger-safe construction, compact modular format and robust pressure-plate terminals make it an excellent solution for machinery, automation systems and electrical distribution equipment where reliability and safety are essential. Optional auxiliary microswitches are available separately for applications requiring remote fuse-status indication.
Typical Applications
- Industrial control panels.
- Motor control centres.
- OEM machinery.
- Industrial automation systems.
- Power distribution equipment.
- Process control installations.
- Renewable energy systems.
Technical Specifications
Tick the specs you need, then view products that match.
| Fuse Indication | Visual indicator | |
|---|---|---|
| Phase | Three Phase | |
| Poles | 3-pole | |
| Device Type | Fuse base / holder | |
| Fuse Size | 14x51 mm | |
| Current | 50 A | |
| Voltage | 800 V | |
| Manufacturer | Mersen | |
| Series | UltraSafe™ US14 | |
| Model | US143I | |
| Manufacturer part number | P331144 | |
| EAN / UPC | 0782001311131 | |
| Product type | Modular fuse holder | |
| Fuse size | 14 × 51 mm cylindrical fuse links | |
| Number of poles | 3 | |
| Rated current | 50 A | |
| Rated voltage AC (UL) | 800 V | |
| Rated voltage AC (IEC) | 750 V | |
| Rated voltage DC (UL) | 1000 V | |
| Frequency | 50 / 60 Hz | |
| Fuse indication | Visual blown fuse indicator | |
| Terminal type | Pressure plate | |
| Protection rating | IP20 | |
| Mounting type | DIN rail mounting | |
| Approximate weight | 0.44 kg | |
| HS Code | 85361050 | |
| Country of Manufacture | Tunisia |
Frequently Asked Questions
What is the Mersen P331144 used for?
The P331144 is a three-pole modular fuse holder designed to protect industrial AC and DC electrical circuits using 14×51 mm cylindrical fuse links.
Which fuse size is compatible with the P331144?
It is designed specifically for 14×51 mm cylindrical fuse links.
Does the P331144 include a blown fuse indicator?
Yes. It incorporates an integrated visual blown fuse indicator for rapid local identification of an operated fuse.
Can remote fuse indication be added?
Yes. The UltraSafe™ US14 range supports compatible auxiliary microswitch accessories that can be fitted separately where remote fuse-status signalling is required.
What are the electrical ratings?
The P331144 is rated for 50 A and supports systems up to 800 V AC UL, 750 V AC IEC and 1000 V DC UL.
Trusted by Electrical Professionals Worldwide
Mersen UltraSafe™ fuse holders are trusted by panel builders, OEMs and industrial engineers for delivering dependable circuit protection, finger-safe operation and reliable performance across demanding industrial installations.
