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MERSEN FUSE NH 3 250A 690V AM NH3AM69V250
Mersen NH3AM69V250 DIN NH size 3 aM fuse-link rated at 250 A and 690 V AC, designed for short-circuit protection in industrial motor circuits.
£43.41
Why Choose the Mersen NH3AM69V250 NH Fuse-Link?
The Mersen NH3AM69V250 is a high-performance DIN NH size 3 aM fuse-link designed specifically for short-circuit protection of industrial motor circuits. Rated at 250 A and 690 V AC, it delivers excellent current-limiting performance to safeguard motors, contactors, motor starters and associated switchgear against damaging fault currents.
Featuring an aM partial-range operating characteristic, the NH3AM69V250 is engineered to tolerate the high inrush currents generated during motor starting while providing rapid interruption of severe short-circuit faults. As with all aM fuse-links, it should be coordinated with a suitable overload relay or motor protection device, as overload protection is provided separately.
The fuse-link incorporates a robust ceramic body, silver-plated blade contacts, live gripping lugs and a double fuse-operation indicator. Manufactured to the DIN NH standard, it is suitable for installation in compatible NH fuse bases and switch-fuse disconnectors throughout industrial motor control systems.
Key Advantages
- Purpose-designed aM short-circuit protection for motor circuits.
- 250 A rated current for demanding industrial applications.
- 690 V AC operating voltage.
- 80 kA AC breaking capacity for dependable fault interruption.
- Allows normal motor starting currents without nuisance operation.
- Double indication system enables rapid fuse status identification.
Key Features
- Mersen NH aM 690 V fuse-link series.
- DIN NH size 3.
- 250 A rated current.
- 690 V AC rated voltage.
- Partial-range aM operating characteristic.
- Designed for motor circuit short-circuit protection.
- Double blown-fuse indicator.
- Live, non-isolated gripping lugs.
- Silver-plated copper blade contacts.
- Robust ceramic insulating body.
Reliable Short-Circuit Protection for Motor Circuits
Industrial motors can generate substantial inrush currents during starting. The Mersen NH3AM69V250 is specifically designed to tolerate these temporary currents while rapidly interrupting high-energy short-circuit faults, helping minimise damage to motors and associated electrical equipment.
As an aM fuse-link, the NH3AM69V250 should always be installed alongside a suitable overload protection device. Installation and replacement should only be carried out by qualified electrical professionals using approved NH fuse handling equipment.
Typical Applications
- Industrial motor control centres.
- Direct-on-line motor starters.
- Star-delta motor starter assemblies.
- Industrial pumps, compressors and fans.
- Conveyor and material handling equipment.
- Manufacturing machinery.
- Industrial automation systems.
Technical Specifications
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| Fuse Indication | Dual indicator | |
|---|---|---|
| Current | 250 A | |
| Voltage | 690 V | |
| Device Type | Fuse link | |
| Fuse Type | NH (DIN) | |
| Fuse Size | NH3 | |
| Fuse Class | aM | |
| Manufacturer | Mersen | |
| Series | NH aM 690 V Fuse-Links | |
| Model | NH3AM69V250 | |
| Item number | D227979 | |
| Product type | NH motor circuit fuse-link | |
| Fuse characteristic | aM | |
| Fuse size | NH3 | |
| Rated current | 250 A | |
| Rated voltage | 690 V AC | |
| Current type | AC | |
| Breaking capacity | 80 kA AC | |
| Power dissipation | 14.6 W | |
| Indication system | Double indicator | |
| Gripping lugs | Live / non-isolated | |
| Terminal type | Plain blade contacts | |
| Terminal material | Silver-plated copper | |
| Body width | 71.9 mm | |
| Weight | approx. 1.05 kg | |
| EAN | 8430399025346 | |
| Compliance | RoHS compliant | |
| HS Code | 85361090 | |
| Country of Manufacture | Hungary |
Frequently Asked Questions
What is the Mersen NH3AM69V250 used for?
This fuse-link provides short-circuit protection for industrial motor circuits, motor starters and associated switching equipment.
What is the current rating of this fuse-link?
The Mersen NH3AM69V250 has a rated current of 250 A.
What voltage is the NH3AM69V250 rated for?
It is designed for operation on electrical systems up to 690 V AC.
What does the aM fuse characteristic mean?
The aM characteristic identifies a partial-range motor protection fuse that tolerates motor starting currents while providing reliable short-circuit protection.
Does this fuse require separate overload protection?
Yes. The NH3AM69V250 must always be coordinated with an appropriate overload relay or motor protection device because an aM fuse-link provides short-circuit protection only.
Trusted Motor Circuit Protection
Mersen NH aM fuse-links are trusted by electrical engineers, OEM machine builders and industrial maintenance professionals worldwide for dependable motor circuit protection, excellent current limitation and long-term operational reliability.
