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MERSEN FUSE 300V 40A T FUSE A3T40
Fast-acting Class T fuse designed for reliable circuit protection in industrial power distribution systems with ratings of 300VAC and 160VDC at 400A.
£18.63
Why Choose the Mersen A3T40 Class T Fuse?
The Mersen A3T40 is a compact and highly reliable Class T fast-acting fuse designed to provide superior overcurrent and short-circuit protection for industrial and commercial electrical systems. As part of the trusted Mersen Amp-Trap® A3T series, it delivers exceptional current-limiting performance while maintaining a compact footprint, making it ideal for installations where both protection and space efficiency are essential.
Designed to interrupt fault currents rapidly, the A3T40 helps minimise damage to switchgear, conductors and connected equipment by significantly reducing thermal and mechanical stress during fault conditions. Its unique Class T dimensions prevent replacement with lower-performance fuse types, helping maintain electrical safety and compliance.
With a rated current of 40 A, a 300 V AC / 160 V DC voltage rating and a fast-acting characteristic, the Mersen A3T40 is ideal for protecting load centres, panelboards, switchboards, circuit breakers, metering centres and industrial control equipment.
Key Advantages
- Compact Class T fast-acting industrial fuse.
- 40 A current rating for industrial and commercial protection.
- 300 V AC and 160 V DC voltage rating.
- Extremely current-limiting design reduces equipment damage.
- Fast interruption improves electrical system safety.
- Unique Class T dimensions prevent incorrect fuse substitution.
Key Features
- Mersen Amp-Trap® A3T Class T series.
- 40 A rated current.
- 300 V AC / 160 V DC rated voltage.
- Fast-acting overcurrent protection.
- High interrupting capacity of 200 kA AC.
- Glass melamine body for dimensional stability.
- Ferrule terminal construction.
- Compact design for compatible Class T fuse holders.
Reliable Protection for Industrial Electrical Systems
Fast-acting Class T fuses are engineered to interrupt excessive fault currents before significant damage occurs. Their current-limiting performance reduces arc energy, minimises thermal stress and helps extend the service life of electrical equipment.
The Mersen A3T40 combines compact dimensions with high interrupting capacity, making it an excellent solution for modern electrical distribution systems requiring dependable overcurrent protection and efficient use of panel space.
Typical Applications
- Load centres.
- Panelboards.
- Switchboards.
- Circuit breakers.
- Metering centres.
- Industrial control panels and OEM equipment.
Technical Specifications
Tick the specs you need, then view products that match.
| Current | 40 A | |
|---|---|---|
| Voltage | 300 V | |
| Fuse Type | UL class | |
| Fuse Class | Fast acting | |
| Item number | A3T400 | |
| Description | Fuse A3T - Class T - Fast-Acting 300VAC 160VDC 400A Blade Amp-Trap® | |
| EAN/UPC Code | 782001890285 | |
| Rated voltage AC UL | 300 V | |
| Rated voltage DC UL | 160 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 400 A | |
| AC or DC | AC/DC | |
| Fuse Class | Class T | |
| Speed/Characteristic | Fast-Acting | |
| Mounting | Bolted | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Connection/Terminal Material | Copper | |
| Connection/Terminal Type | Blade | |
| Product Diameter | 33.8 mm | |
| Product Length | 69.8 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 0.1315 kg | |
| Sell Pack Width | 35.1 mm | |
| Sell Pack Length | 35.1 mm | |
| Sell Pack Height | 73.2 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 0.1234 kg | |
| HS Code | 85361050 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A3T40 used for?
The A3T40 protects industrial and commercial electrical circuits against overloads and short circuits using fast-acting Class T fuse technology.
What is the current rating of the A3T40?
The fuse has a continuous current rating of 40 A.
What voltage is this fuse rated for?
The Mersen A3T40 is rated for 300 V AC and 160 V DC applications.
Why choose a Class T fuse?
Class T fuses provide extremely high current limitation, compact dimensions and unique sizing that prevents replacement with lower-performance fuse types.
Where is the A3T40 typically installed?
It is commonly installed in load centres, panelboards, switchboards, circuit breakers, metering centres and industrial control panels.
Trusted for Critical Circuit Protection
Mersen Amp-Trap® Class T fuses are trusted by electrical engineers, OEMs and panel builders worldwide for providing reliable current limitation, fast fault interruption and dependable protection for industrial power distribution systems.
