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MERSEN FUSE 600V 70A CLASS J FUSE A4J70
The Fuse A4J70 delivers rapid short-circuit protection, minimising the risk of equipment damage and downtime in demanding industrial applications. Designed to operate at up to 600VAC and 300VDC with a 70A rating, it ensures precise, fast-acting response where reliable circuit protection is essential.
£42.53
Why Choose the Mersen A4J70 Amp-Trap Fuse?
The Mersen A4J70 is a high-performance Class J fast-acting current-limiting fuse designed to protect industrial and commercial electrical systems against damaging overcurrents and short circuits. Part of the established Mersen Amp-Trap A4J series, it provides rapid fault interruption for feeder circuits, branch circuits, switchboards, control panels and general-purpose electrical equipment.
During a short-circuit event, the A4J70 limits the peak fault current and total let-through energy reaching downstream components. This helps reduce thermal and mechanical stress on conductors, busbars, switches and other electrical equipment, supporting improved system reliability and reducing the risk of costly damage.
With a rated current of 70 A, a 600 V AC rating and a 300 V DC rating, the Mersen A4J70 is suitable for demanding AC and DC circuit-protection applications. Its Class J rejection design helps prevent substitution with fuses that have unsuitable voltage, interrupting or current-limiting characteristics.
Key Advantages
- Fast-acting Class J fuse for industrial circuit protection.
- 70 A current rating for feeders, branch circuits and equipment.
- 600 V AC and 300 V DC voltage ratings.
- Current-limiting operation helps reduce damaging fault energy.
- 200 kA AC interrupting rating for high-fault-current installations.
- Class J rejection design helps prevent unsuitable fuse substitution.
Key Features
- Mersen Amp-Trap A4J series.
- 70 A rated current.
- 600 V AC voltage rating.
- 300 V DC voltage rating.
- Fast-acting current-limiting performance.
- Blade-terminal construction.
- High interrupting capacity for demanding electrical systems.
- Compatible with correctly rated Class J fuse holders.
Reliable Protection for Industrial Electrical Systems
Current-limiting fuses such as the Mersen A4J70 interrupt high fault currents before they can reach their maximum prospective level. By restricting peak current and total let-through energy, the fuse helps protect downstream equipment from excessive heat, electromagnetic forces and other damaging effects associated with short-circuit conditions.
The Amp-Trap A4J range combines fast operation, high interrupting capacity and Class J rejection features. This makes the A4J70 a dependable choice for installations where reliable fault protection, efficient coordination and correct fuse selection are essential.
Typical Applications
- Industrial feeder circuits.
- Branch-circuit protection.
- Panelboards and switchboards.
- Industrial control panels.
- Load centres and distribution equipment.
- Lighting and heating circuits.
- Industrial machinery and general-purpose electrical loads.
Technical Specifications
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| Current | 70 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Fast acting | |
| Item number | A4J70 | |
| Description | Fuse A4J - Class J - Fast-Acting 600VAC 300VDC 70A Blade Amp-Trap® | |
| EAN/UPC Code | 782001960285 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 300 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 70 A | |
| AC or DC | AC/DC | |
| Fuse Class | Class J | |
| Speed/Characteristic | Fast-Acting | |
| Mounting | Clip | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Connection/Terminal Material | Silver-Plated Copper | |
| Connection/Terminal Type | Blade | |
| Product Diameter | 27 mm | |
| Product Length | 117.6 mm | |
| Sell Pack Quantity | 5 EA | |
| Sell Pack Weight | 0.5715 kg | |
| Sell Pack Width | 136.7 mm | |
| Sell Pack Length | 152.4 mm | |
| Sell Pack Height | 26.9 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 0.1089 kg | |
| HS Code | 85361090 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4J70 used for?
The Mersen A4J70 provides fast-acting overcurrent and short-circuit protection for industrial feeders, branch circuits, switchboards, control panels and electrical equipment.
What is the current rating of the A4J70 fuse?
The A4J70 has a rated current of 70 A.
What voltage is the Mersen A4J70 rated for?
The fuse is rated for operation at up to 600 V AC and 300 V DC.
Is the A4J70 a time-delay fuse?
No. The A4J70 is a fast-acting Class J current-limiting fuse designed to interrupt overcurrents and short-circuit faults rapidly.
What fuse holder is required for the A4J70?
The A4J70 should be installed in a compatible Class J fuse holder rated for a 70 A fuse and the applicable system voltage.
What terminals does the Mersen A4J70 use?
The A4J70 uses blade terminals and is designed for clip mounting in a compatible Class J fuse holder.
Trusted Industrial Circuit Protection
Mersen Amp-Trap Class J fuses are widely specified by electrical engineers, panel builders, OEMs and maintenance professionals for dependable current limitation and high-performance protection in demanding industrial electrical systems.
