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MERSEN FUSE US142M US142M
Mersen J331139 UltraSafe US142M 2-pole modular fuse holder for 14 × 51 mm cylindrical fuse-links with two auxiliary microswitches, 50 A rating, DIN rail mounting and IP20 finger-safe protection.
£40.46
Why Choose the Mersen J331139 UltraSafe™ US142M Fuse Holder?
The Mersen J331139, catalogue number US142M, is a premium 2-pole UltraSafe™ modular fuse holder designed for protecting industrial power distribution, machinery and electrical control systems. It accepts standard 14 × 51 mm cylindrical fuse-links and incorporates two auxiliary microswitches to provide reliable remote fuse-status indication for automation and monitoring systems.
Part of the advanced Mersen UltraSafe™ US14 range, the US142M features a robust finger-safe IP20 housing, pressure-plate terminals and DIN rail mounting. Its modular construction simplifies installation while providing secure electrical connections and dependable long-term performance in demanding industrial environments.
Rated at 50 A, with 800 V AC and 1000 V DC UL ratings, the J331139 is ideal for motor protection, transformers, industrial automation, variable speed drives and power conversion equipment where remote monitoring of fuse operation is required.
Key Advantages
- Designed for 14 × 51 mm cylindrical fuse-links.
- 2-pole configuration for industrial AC and DC circuits.
- Integrated two auxiliary microswitches for remote fuse monitoring.
- 50 A current rating.
- Suitable for systems up to 800 V AC and 1000 V DC.
- IP20 finger-safe protection during operation and fuse replacement.
- Compact DIN rail mounting saves valuable panel space.
Key Features
- Mersen UltraSafe™ US14 series.
- Catalogue number: US142M.
- Manufacturer part number: J331139.
- 2-pole modular fuse holder.
- Compatible with 14 × 51 mm cylindrical fuse-links.
- 50 A conventional free-air thermal current.
- 800 V AC / 1000 V DC UL ratings.
- Two integrated auxiliary microswitches.
- Pressure-plate terminal connections.
- DIN rail mounting.
- IP20 finger-safe construction.
- Lockable, sealable modular design.
Reliable Circuit Protection with Remote Monitoring
The Mersen J331139 securely accommodates two 14 × 51 mm cylindrical fuse-links while providing remote signalling through its integrated auxiliary microswitches. When a compatible fuse operates, the microswitches can be connected to PLCs, alarms or SCADA systems to provide rapid fault notification and reduce machine downtime.
Its compact UltraSafe™ construction combines excellent operator safety with high electrical performance, making it an ideal choice for industrial machinery, power distribution systems and automation equipment requiring dependable overcurrent protection and remote diagnostics.
Typical Applications
- Industrial control panels.
- Variable speed drives.
- Motor and transformer protection.
- Power conversion equipment.
- Industrial automation systems.
- PLC monitoring circuits.
- OEM machinery.
- Low-voltage power distribution.
Technical Specifications
Tick the specs you need, then view products that match.
| Fuse Indication | Microswitch | |
|---|---|---|
| Poles | 2-pole | |
| Device Type | Fuse base / holder | |
| Fuse Type | Cylindrical | |
| Fuse Size | 14x51 mm | |
| Current | 50 A | |
| Voltage | 800 V | |
| Manufacturer | Mersen | |
| Series | UltraSafe™ US14 | |
| Catalogue number | US142M | |
| Manufacturer part number | J331139 | |
| Product type | Modular cylindrical fuse holder | |
| Fuse size | 14 × 51 mm | |
| Number of poles | 2 | |
| Rated current | 50 A | |
| Rated voltage AC | 800 V UL | |
| Rated voltage DC | 1000 V UL | |
| IEC rated voltage | 690 V AC / DC | |
| Short-circuit current rating | 200 kA | |
| Auxiliary contacts | Two integrated microswitches | |
| Connection type | Pressure plate terminals | |
| Protection rating | IP20 | |
| Mounting type | DIN rail | |
| Housing material | Polyamide thermoplastic | |
| Dimensions (H × W × D) | Approx. 111 × 53 × 76 mm | |
| Weight | Approx. 0.31 kg | |
| RoHS compliant | Yes | |
| HS Code | 85361050 | |
| Country of Manufacture | Tunisia |
Frequently Asked Questions
What fuse size does the Mersen J331139 accept?
The J331139 accepts standard 14 × 51 mm cylindrical fuse-links.
What is the purpose of the integrated microswitches?
The two auxiliary microswitches provide remote fuse-status indication for PLCs, alarm systems and industrial monitoring equipment.
What are the electrical ratings of the US142M?
The fuse holder is rated at 50 A, up to 800 V AC and 1000 V DC under UL ratings, with IEC ratings up to 690 V AC/DC.
Is the J331139 finger-safe?
Yes. The UltraSafe™ design provides IP20 finger-safe protection, including during fuse replacement.
How is the Mersen J331139 installed?
The fuse holder mounts directly onto a standard DIN rail using its modular housing for quick installation inside electrical control panels.
Trusted by Industrial Electrical Professionals
Mersen UltraSafe™ fuse holders are trusted worldwide by panel builders, OEM manufacturers and industrial engineers for dependable circuit protection, remote fuse monitoring and long-term reliability in demanding electrical installations.
