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MERSEN FUSE US142MI US142MI
Mersen K331140 US142MI UltraSafe two-pole modular fuse holder for 14 x 51 mm cylindrical fuse links, rated 50 A with visual blown-fuse indication, auxiliary microswitch and IP20 protection.
£55.38
Why Choose the Mersen K331140 US142MI UltraSafe Fuse Holder?
The Mersen K331140, catalogue reference US142MI, is a robust two-pole modular fuse holder designed for 14 × 51 mm cylindrical fuse links. Part of the Mersen UltraSafe™ US14 series, it provides dependable overcurrent protection for industrial control, power distribution and equipment protection applications.
This fuse holder combines a visual blown-fuse indicator with auxiliary microswitch functionality, helping maintenance teams identify operated fuse links and remotely monitor fuse or holder status. Its finger-safe IP20 construction improves protection during installation, operation and fuse replacement.
Rated for currents up to 50 A, the K331140 supports IEC voltages up to 750 V AC/DC and UL ratings of 800 V AC and 1000 V DC. Its compact DIN rail mounted format, durable polyamide body and pressure-plate terminals make it suitable for demanding electrical panels and machinery.
Key Advantages
- Two-pole UltraSafe™ modular fuse holder for 14 × 51 mm fuse links.
- 50 A maximum fuse rating for industrial circuit protection.
- Integrated visual blown-fuse indication.
- Auxiliary microswitch supports remote status signalling.
- IP20 finger-safe protection, including during fuse replacement.
- DIN rail mounting enables quick panel installation.
- High 100 kA short-circuit current rating.
- Suitable for both AC and DC electrical systems.
Key Features
- Mersen UltraSafe™ US14 series.
- Catalogue number: US142MI.
- Manufacturer item number: K331140.
- Two-pole configuration.
- Accepts 14 × 51 mm cylindrical fuse links.
- Visual indicator and auxiliary microswitch.
- 50 A rated current.
- IEC voltage rating up to 750 V AC/DC.
- UL voltage rating up to 800 V AC and 1000 V DC.
- Pressure-plate terminals with tin-plated copper connections.
- DIN rail mounting to EN 60715.
- Lockable and sealable modular design.
Reliable Circuit Protection with Remote Indication
The Mersen K331140 provides a secure and convenient method of installing cylindrical fuse links within electrical control panels and distribution equipment. The two-pole configuration allows two conductors or phases to be protected within one compact modular device.
Its visual indicator helps personnel quickly identify a blown fuse when the circuit remains energised. The auxiliary microswitch can also provide remote signalling for fuse operation, holder opening or fuse presence, depending on the circuit design and fuse link used.
Typical Applications
- Industrial control panels.
- Motor and transformer protection circuits.
- Low voltage power distribution.
- Semiconductor and power electronic equipment.
- OEM machinery and automation systems.
- Renewable energy and power conversion equipment.
- Commercial and industrial switchboards.
Technical Specifications
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| Fuse Indication | Microswitch, Visual indicator | |
|---|---|---|
| Poles | 2-pole | |
| Device Type | Fuse base / holder | |
| Fuse Type | Cylindrical | |
| Fuse Size | 14x51 mm | |
| Voltage | 750 V | |
| Manufacturer | Mersen | |
| Series | UltraSafe™ US14 | |
| Catalogue number | US142MI | |
| Item number | K331140 | |
| Product type | Modular cylindrical fuse holder | |
| Number of poles | 2 | |
| Fuse size | 14 × 51 mm | |
| Maximum fuse rating | 50 A | |
| Rated voltage, IEC | 750 V AC / 750 V DC | |
| Rated voltage, UL | 800 V AC / 1000 V DC | |
| Rated insulation voltage | 690 V | |
| Rated impulse withstand voltage | 8 kV | |
| Short-circuit current rating | 100 kA | |
| Frequency | 50 / 60 Hz | |
| Indication | Visual indicator and auxiliary microswitch | |
| Protection rating | IP20 | |
| Mounting type | DIN rail to EN 60715 | |
| Terminal type | Pressure plate / clip connection | |
| Terminal material | Tin-plated copper | |
| Rigid conductor range | 1.5–35 mm² | |
| Stranded conductor range | 1.5–25 mm² | |
| Maximum tightening torque | 3.5 Nm | |
| Body material | Polyamide | |
| Operating temperature | -25°C to +60°C | |
| Dimensions (H × W × D) | approx. 110.7 × 53.1 × 76.5 mm | |
| Weight | approx. 0.31 kg | |
| Compliance | UL 4248, CSA C22.2, IEC 60269-2, IEC 60947-3 and RoHS | |
| HS Code | 85361050 | |
| Country of Manufacture | Tunisia |
Frequently Asked Questions
What is the Mersen K331140 used for?
The K331140 is a two-pole modular fuse holder used to install 14 × 51 mm cylindrical fuse links in industrial AC and DC circuit protection applications.
What fuse size does the K331140 accept?
It is designed for standard 14 × 51 mm cylindrical fuse links with a maximum fuse rating of 50 A.
Does the K331140 include fuse indication?
Yes. The US142MI includes a visual blown-fuse indicator and auxiliary microswitch functionality for local and remote status monitoring.
What voltage ratings does this fuse holder support?
It is rated up to 750 V AC/DC under IEC standards, with UL ratings of 800 V AC and 1000 V DC.
How is the Mersen K331140 installed?
The fuse holder mounts onto a standard DIN rail in accordance with EN 60715 and uses pressure-plate terminals for secure conductor connections.
Trusted by Industrial Panel Builders Worldwide
Mersen UltraSafe™ fuse holders are widely specified by electrical engineers, OEM manufacturers and panel builders for reliable circuit protection, finger-safe operation and efficient maintenance in demanding installations.
