MERSEN FUSE NH 3 400A 500V AM NH3AM50V400

MERSEN FUSE NH 3 400A 500V AM NH3AM50V400

Mersen NH3AM50V400 NH Size 3 aM low voltage fuse link rated at 400 A and 500 V AC, with a 120 kA breaking capacity, double indicator and live gripping lugs for industrial motor circuit short-circuit protection.

SKU: NH3AM50V400Alt SKU: NH3AM50V400MPN: R232522
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List Price £34.32 ex VAT
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Why Choose the Mersen NH3AM50V400 NH Fuse Link?

The Mersen NH3AM50V400 is a high-performance NH aM low voltage fuse link designed specifically to provide short-circuit protection for high-power motor circuits and industrial electrical equipment. As part of the established Mersen NH aM fuse-link series, it delivers strong current-limiting performance and dependable fault interruption in demanding motor control and power distribution applications.

With a 400 A rated current and a 500 V AC operating voltage, this NH3 fuse link is suitable for protecting large motors, motor starters and associated switchgear. Its high 120 kA AC breaking capacity enables it to safely interrupt substantial prospective fault currents before serious damage occurs.

The NH3AM50V400 features a durable ceramic body, silver-plated copper blade contacts and live gripping lugs for handling with an approved NH fuse puller. A double indicator provides clear visual confirmation when the fuse has operated, helping maintenance teams identify faults quickly and minimise industrial downtime.

Key Advantages

  • Specialist aM fuse link for high-power motor circuit protection.
  • 400 A rated current for demanding industrial motor applications.
  • 500 V AC rated operating voltage.
  • High 120 kA breaking capacity for reliable fault interruption.
  • Strong current-limiting performance helps reduce thermal and mechanical stress.
  • Double indicator allows rapid identification of an operated fuse.

Key Features

  • Mersen NH aM fuse-link series.
  • NH Size 3 construction.
  • 400 A rated current.
  • 500 V AC rated voltage.
  • aM operating characteristic for motor circuit short-circuit protection.
  • 120 kA maximum AC breaking capacity.
  • Double visual operating indicator.
  • Live gripping lugs for use with an appropriate NH fuse puller.
  • Silver-plated copper blade contacts.
  • Robust ceramic insulating body.

Reliable Short-Circuit Protection for High-Power Motors

The Mersen NH3AM50V400 is engineered to interrupt damaging short-circuit currents in large industrial motor circuits. Its aM characteristic allows normal motor starting currents to pass while rapidly disconnecting the circuit when a severe electrical fault occurs.

Because aM fuse links provide partial-range protection, the NH3AM50V400 must be used with a correctly selected overload relay, motor protection circuit breaker or other suitable overload protection device. When properly coordinated, this combination provides effective protection for motors, cables, contactors and associated control equipment.

Typical Applications

  • High-power industrial motor circuits.
  • Motor control centres.
  • Industrial motor starters and contactor assemblies.
  • Pumps, compressors and ventilation systems.
  • Manufacturing and processing machinery.
  • Industrial switchboards and distribution equipment.

Technical Specifications

Current 400 A
Voltage 500 V
Manufacturer Mersen
Item number R232522
Series NH Fuse Links aM 500 VAC
Model NH3AM50V400
EAN / UPC 8430399026916
Product type NH low voltage fuse link
Fuse size NH3
Rated current 400 A
Rated voltage 500 V AC
Operating characteristic aM
Maximum AC breaking capacity 120 kA
Protection type Motor circuit short-circuit protection
Indicator Double indicator
Gripping lugs Live gripping lugs
Terminal type Plain blades
Terminal material Silver-plated copper
Body material Ceramic
Dimensions (L × W × H) Approx. 150 × 72 × 89 mm
Body width 71.9 mm
Power dissipation at rated current 29.1 W
Weight Approx. 1.05 kg
RoHS compliant Yes
HS Code 85361090
Country of Manufacture Hungary
Device Type Fuse link
Fuse Type NH (DIN)
Fuse Size NH3
Fuse Class aM

Frequently Asked Questions

What is the Mersen NH3AM50V400 used for?

This NH fuse link provides short-circuit protection for high-power industrial motors, motor starters, contactors and associated electrical equipment.

What is the rated current of this fuse?

The Mersen NH3AM50V400 has a rated current of 400 A.

What does the aM operating characteristic mean?

An aM fuse is a partial-range fuse designed specifically for motor circuit short-circuit protection. It must be combined with a separate overload protection device.

What is the breaking capacity of the NH3AM50V400?

The fuse link has a maximum AC breaking capacity of 120 kA, allowing it to interrupt high prospective fault currents safely.

What fuse holder is required?

The NH3AM50V400 must be installed in a compatible NH Size 3 fuse base rated for the system voltage, operating current and available fault level.

Trusted for Industrial Motor Protection

Mersen NH aM fuse links are widely used by electrical engineers, panel builders and industrial maintenance teams to provide reliable, current-limiting short-circuit protection for demanding motor applications.

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