MERSEN FUSE US143M2 US143M2

Q: What makes the US143M2 different from the standard version?

The US143M2 incorporates two connected microswitches, providing enhanced remote monitoring of fuse status for industrial control systems.

Q: What fuse size does this holder accept?

It is designed for standard 14 × 51 mm cylindrical fuse links.

Q: What are the voltage and current ratings?

The fuse holder is rated for 50 A, 800 V AC UL, 1000 V DC UL and 750 V AC IEC.

Mersen T331148 US143M2 UltraSafe three-pole modular fuse holder for 14 x 51 mm cylindrical fuse links featuring two connected microswitches, 50 A rating, IP20 protection and DIN rail mounting.

SKU: T331148Alt SKU: US143M2MPN: T331148

List Price £83.42 ex VAT

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£83.42

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Manufacturer Lead Time

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Why Choose the Mersen T331148 US143M2 UltraSafe™ Fuse Holder?

The Mersen T331148, catalogue reference US143M2, is a premium three-pole modular fuse holder engineered for reliable protection of industrial electrical systems using 14 × 51 mm cylindrical fuse links. As part of the proven Mersen UltraSafe™ US14 series, it combines high electrical performance with an innovative finger-safe design and dual microswitch functionality for advanced remote monitoring.

Unlike standard fuse holders, the US143M2 incorporates two connected microswitches, allowing enhanced remote indication of fuse status for PLCs, alarm systems and industrial automation equipment. Its pressure-plate terminals provide secure conductor termination, whilst the IP20 finger-safe construction enables safer fuse replacement during maintenance.

Rated for 50 A, with UL voltage ratings of 800 V AC and 1000 V DC, together with an IEC rating of 750 V AC, the Mersen T331148 is ideally suited to industrial machinery, switchboards, photovoltaic installations and automation systems requiring dependable overcurrent protection and remote monitoring.

Key Advantages

Three-pole UltraSafe™ modular fuse holder.
Designed for 14 × 51 mm cylindrical fuse links.
Integrated dual connected microswitches for advanced remote monitoring.
50 A current rating.
Suitable for demanding AC and DC industrial applications.
IP20 finger-safe construction improves operator safety.

Key Features

Mersen UltraSafe™ US14 series.
Three-pole modular fuse holder.
Accepts 14 × 51 mm cylindrical fuse links.
50 A rated current.
800 V AC UL rated voltage.
1000 V DC UL rated voltage.
750 V AC IEC rated voltage.
Integrated two connected microswitches.
Pressure-plate terminal connections.
DIN rail mounting with IP20 finger-safe protection.

Advanced Remote Monitoring for Industrial Protection

The Mersen T331148 securely houses three cylindrical fuse links whilst providing dependable overcurrent protection for industrial electrical systems. Its UltraSafe™ finger-safe construction improves operator safety during installation and maintenance, whilst the dual microswitch arrangement provides enhanced monitoring capability for critical applications.

Designed for OEM machinery, industrial automation, power distribution systems and photovoltaic installations, the US143M2 helps reduce maintenance time by enabling remote indication of fuse operation through industrial control systems and monitoring equipment.

Typical Applications

Industrial control panels.
Motor control centres.
Power distribution systems.
Photovoltaic installations.
OEM machinery.
Industrial automation systems with remote monitoring.

Technical Specifications

Phase	Three Phase
Manufacturer	Mersen
Series	UltraSafe™ US14
Item number	T331148
Catalogue number	US143M2
Product type	Modular cylindrical fuse holder
Fuse size	14 × 51 mm
Number of poles	3
Rated current	50 A
Rated voltage AC (UL)	800 V
Rated voltage DC (UL)	1000 V
Rated voltage AC (IEC)	750 V
Frequency	50 / 60 Hz
Microswitches	Two connected microswitches
Terminal type	Pressure plate
Protection rating	IP20
Mounting type	DIN rail
EAN / UPC	0782001311100
HS Code	85361050
Country of Manufacture	Tunisia
Poles	3-pole
Device Type	Fuse base / holder
Fuse Type	Cylindrical
Fuse Size	14x51 mm
Current	50 A
Voltage	800 V

Frequently Asked Questions

What is the Mersen T331148 used for?

The Mersen T331148 is a three-pole modular fuse holder designed for 14 × 51 mm cylindrical fuse links in industrial AC and DC electrical systems.

What makes the US143M2 different from the standard version?

The US143M2 incorporates two connected microswitches, providing enhanced remote monitoring of fuse status for industrial control systems.

What fuse size does this holder accept?

It is designed for standard 14 × 51 mm cylindrical fuse links.

What are the voltage and current ratings?

The fuse holder is rated for 50 A, 800 V AC UL, 1000 V DC UL and 750 V AC IEC.

How is the Mersen T331148 installed?

It is designed for DIN rail mounting using pressure-plate terminals for secure electrical connections.

Trusted by Industrial Engineers Worldwide

Mersen UltraSafe™ fuse holders are trusted worldwide by OEMs, panel builders and industrial engineers for dependable circuit protection, advanced monitoring capabilities and long-term operational reliability.

UK delivery

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Send your order number, product details and reason for return. For faults or delivery damage, include photographs if available. We will confirm the next steps.

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