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MERSEN FUSE NH 4A 1250A 500V AM NH4AAM50V1250-8
Mersen NH4AAM50V1250-8 NH4a size aM fuse link rated at 1250 A and 500 V AC, designed to provide high-capacity short-circuit protection for large industrial motors and electrical equipment.
£113.03
Why Choose the Mersen NH4AAM50V1250-8 NH Fuse Link?
The Mersen NH4AAM50V1250-8 is a high-capacity NH4a size aM fuse link designed to provide reliable short-circuit protection for large industrial motors, motor starters and high-power electrical equipment. Rated at 1250 A and 500 V AC, it is suitable for demanding motor control and industrial power distribution applications.
Its aM operating characteristic allows the fuse to withstand the temporary inrush currents produced during motor starting while rapidly interrupting severe short-circuit currents. As an aM fuse provides partial-range protection, the NH4AAM50V1250-8 must be coordinated with a correctly selected overload relay or another suitable overload protection device.
The fuse link features a robust industrial construction with standard blade contacts, live gripping tags and an integrated top fuse indicator. Its 100 mm body width and NH4a format enable installation in compatible heavy-duty fuse bases, fuse switches and disconnectors used in high-current electrical systems.
Key Advantages
- Purpose-designed aM short-circuit protection for large motor circuits.
- 1250 A rated current for high-power industrial equipment.
- 500 V AC voltage rating for low-voltage power systems.
- High 120 kA AC breaking capacity for severe fault conditions.
- Withstands normal motor starting currents without unnecessary operation.
- Top indicator supports quick identification of an operated fuse.
Key Features
- Mersen NH aM industrial fuse-link range.
- NH4a standard fuse size.
- 1250 A rated current.
- 500 V AC rated voltage.
- aM partial-range motor protection characteristic.
- 120 kA maximum AC breaking capacity.
- Integrated top fuse-operation indicator.
- Live gripping tags for use with suitable NH handling equipment.
- Standard blade terminals for compatible fuse bases and disconnectors.
- 100 mm body width for NH4a installations.
Reliable Short-Circuit Protection for High-Power Motors
Large industrial motors can draw substantial inrush currents during start-up. The Mersen NH4AAM50V1250-8 is engineered to tolerate these temporary current peaks while rapidly interrupting dangerous short-circuit currents. This helps reduce thermal and electrodynamic stress on motors, cables, contactors, busbars and associated switchgear.
Because the NH4AAM50V1250-8 has an aM characteristic, it does not provide complete overload protection when used alone. A suitable thermal or electronic overload relay must form part of the motor protection system. Installation and replacement should only be undertaken by qualified electrical personnel using approved NH handling equipment and appropriate personal protective equipment.
Typical Applications
- Large industrial motors and motor starter circuits.
- Motor control centres and heavy-duty control panels.
- Industrial pumps, compressors and ventilation equipment.
- Conveyors, crushers and material handling machinery.
- Manufacturing and processing installations.
- High-current switchgear and power distribution systems.
Technical Specifications
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| Current | 1250 A | |
|---|---|---|
| Voltage | 500 V | |
| Device Type | Fuse link | |
| Fuse Type | NH (DIN) | |
| Fuse Size | NH4a | |
| Fuse Class | aM | |
| Manufacturer | Mersen | |
| Series | NH Fuse Links aM 500 V AC | |
| Model | NH4AAM50V1250-8 | |
| Manufacturer item number | W233561 | |
| Product type | NH motor-protection fuse link | |
| Fuse size | NH4a | |
| Utilisation category | aM | |
| Rated current | 1250 A | |
| Rated voltage | 500 V AC | |
| Maximum AC breaking capacity | 120 kA | |
| Protection range | Partial range / short-circuit protection | |
| Indicator type | Top indicator | |
| Gripping-tag design | Live tags | |
| Terminal type | Blade contacts | |
| Mounting type | Compatible NH4a fuse base or switch disconnector | |
| Body width | 100 mm | |
| Approximate body dimensions | 91.1 × 100 × 109 mm | |
| EAN / UPC | 8430399027920 | |
| Standards | DIN NH and IEC fuse-link requirements | |
| Compliance | RoHS compliant | |
| HS Code | 85361090 | |
| Country of Manufacture | Hungary |
Frequently Asked Questions
What is the Mersen NH4AAM50V1250-8 used for?
This fuse link provides short-circuit protection for large industrial motors, motor starters and associated high-current electrical equipment.
What is the current rating of the NH4AAM50V1250-8?
The Mersen NH4AAM50V1250-8 has a rated current of 1250 A.
What voltage is this fuse rated for?
The NH4AAM50V1250-8 is rated for operation at up to 500 V AC.
What does the aM fuse classification mean?
The aM classification identifies a partial-range fuse designed to protect motor circuits against short circuits while tolerating normal motor starting currents.
Does this fuse provide overload protection?
No. The aM fuse primarily provides short-circuit protection and must be used with a suitable overload relay or another correctly selected overload protection device.
Trusted High-Current Motor Protection
Mersen NH aM fuse links are widely used by panel builders, electrical engineers and industrial maintenance teams to provide dependable short-circuit protection for high-power motors and heavy industrial machinery.
