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MERSEN FUSE NH 4 400A 500V AM NH4AM50V400-8
Mersen NH4AM50V400-8 DIN NH size 4 aM fuse-link rated at 400 A and 500 V AC, providing current-limiting short-circuit protection for heavy-duty industrial motor circuits.
£104.98
Why Choose the Mersen NH4AM50V400-8 NH Fuse-Link?
The Mersen NH4AM50V400-8 is a heavy-duty DIN NH aM fuse-link developed specifically for the short-circuit protection of high-power industrial motor circuits. Manufactured by Mersen, this NH size 4 fuse-link delivers strong current-limiting performance whilst allowing normal motor starting currents to pass without unnecessary fuse operation.
As part of the proven Mersen NH aM 500 V fuse-link series, the NH4AM50V400-8 features a robust ceramic body, silver-plated copper blade contacts, live gripping lugs and a top-mounted indication system. Its large NH4 construction is suited to demanding motor control centres, industrial switchboards and machinery installations carrying substantial operating currents.
With a rated current of 400 A, a rated operating voltage of 500 V AC and a high 120 kA AC breaking capacity, the NH4AM50V400-8 provides dependable protection against severe short-circuit currents. As an aM fuse-link, it must be coordinated with a suitable overload relay or motor protection device to provide complete motor circuit protection.
Key Advantages
- Purpose-designed aM fuse-link for heavy-duty motor circuit protection.
- 400 A rated current for high-power industrial motor applications.
- 500 V AC rated voltage for low-voltage power systems.
- High 120 kA AC breaking capacity for reliable fault interruption.
- Strong current-limiting performance helps protect contactors, starters and cables.
- Top indicator enables quick identification of an operated fuse-link.
Key Features
- Mersen NH aM 500 V fuse-link series.
- DIN NH size 4 construction.
- 400 A rated current.
- 500 V AC rated voltage.
- aM partial-range characteristic for motor circuit protection.
- Live gripping lugs for use with a suitable LV HRC fuse puller.
- Top-mounted fuse status indicator.
- Ceramic body with silver-plated copper blade contacts.
Reliable Motor Circuit Protection
aM fuse-links are partial-range protective devices designed specifically for motor circuits. They interrupt currents from approximately 6.3 times their rated current up to their maximum breaking capacity, whilst tolerating the temporary inrush currents produced during normal motor starting.
The NH4AM50V400-8 provides short-circuit protection only and must be combined with a thermal overload relay, motor protection circuit breaker or another suitable overload device. This coordinated arrangement provides effective protection for motors, contactors, cables and associated switching equipment.
Typical Applications
- Heavy-duty industrial motor control centres.
- Large direct-on-line and reversing motor starters.
- Industrial switchboards and power distribution panels.
- Pumps, fans, compressors and conveyor motor circuits.
- Manufacturing and processing machinery.
- OEM automation and machine-building applications.
Technical Specifications
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| Fuse Indication | Visual indicator | |
|---|---|---|
| Current | 400 A | |
| Voltage | 500 V | |
| Device Type | Fuse link | |
| Fuse Type | NH (DIN) | |
| Fuse Class | aM | |
| Manufacturer | Mersen | |
| Series | NH aM 500 V Fuse-Links | |
| Model | NH4AM50V400-8 | |
| Manufacturer part number | P233555 | |
| EAN / UPC | 8430399027869 | |
| Product type | DIN NH aM fuse-link | |
| Fuse size | NH4 | |
| Rated current | 400 A | |
| Rated voltage | 500 V AC | |
| Utilisation category | aM | |
| AC breaking capacity | 120 kA | |
| Indication system | Top indicator | |
| Gripping-lug design | Live gripping lugs | |
| Terminal type | Plain blades | |
| Terminal material | Silver-plated copper | |
| Body material | Ceramic | |
| Dimensions (L × W × H) | Approx. 200 × 100 × 117 mm | |
| Power dissipation at rated current | 26 W | |
| Product weight | Approx. 2.18 kg | |
| Sell pack quantity | 1 | |
| Mounting | Clip / compatible NH fuse base | |
| Standards | IEC 60269-1, IEC 60269-2 and VDE 0636-201 | |
| RoHS compliant | Yes | |
| HS Code | 85361090 | |
| Country of Manufacture | Hungary |
Frequently Asked Questions
What is the Mersen NH4AM50V400-8 used for?
The NH4AM50V400-8 provides short-circuit protection for high-power industrial motors, contactors, starters and associated motor circuit equipment.
What is the current rating of this fuse-link?
The Mersen NH4AM50V400-8 has a rated current of 400 A.
What voltage is the NH4AM50V400-8 designed for?
This fuse-link is designed for operation in AC electrical systems rated up to 500 V.
What does the aM utilisation category mean?
The aM category identifies a partial-range fuse-link designed for motor circuit short-circuit protection. It permits normal motor starting currents but does not provide overload protection.
Does this fuse-link require separate overload protection?
Yes. The NH4AM50V400-8 must be used with a suitable overload relay, motor protection circuit breaker or equivalent protective device.
Trusted by Electrical Professionals Worldwide
Mersen NH aM fuse-links are widely specified by panel builders, OEMs, electrical contractors and maintenance engineers for dependable motor circuit protection across industrial automation and heavy machinery applications.
