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.
