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MERSEN FUSE L TD FUSE 600V 1800A A4BQ A4BQ1800
High-capacity Class L time-delay fuse rated for 1800A at 600VAC and 500VDC with Amp-Trap 2000® technology for superior protection in industrial applications.
£1,267.53
Why Choose the Mersen A4BQ1800 Class L Fuse?
The Mersen A4BQ1800 is a high-capacity Class L time-delay current-limiting fuse engineered to protect industrial power distribution systems, service entrance equipment and heavy-duty electrical installations against damaging overloads and short circuits. Part of the proven Mersen Amp-Trap 2000 A4BQ series, it delivers effective current limitation while accommodating harmless temporary inrush currents.
Rated at 1800 A, 600 V AC and 500 V DC, the A4BQ1800 is suitable for high-power systems with substantial load currents and available fault levels. Its current-limiting construction reduces short-circuit let-through current, helping protect switchgear, busbars, cables, transformers and other downstream components from severe thermal and mechanical stress.
The fuse features a built-in four-second time delay at 500% of its rated current. This characteristic allows temporary currents associated with motor starting, transformer energisation and other inductive loads to pass without nuisance operation while maintaining dependable protection against sustained overloads and short-circuit faults.
Key Advantages
- Heavy-duty Class L time-delay current-limiting fuse.
- 1800 A current rating for high-capacity power systems.
- 600 V AC and 500 V DC voltage ratings.
- 200 kA AC interrupting rating for high fault-current environments.
- Four-second time delay helps prevent nuisance operation during equipment start-up.
- Advanced current limitation helps reduce damaging short-circuit energy.
Key Features
- Mersen Amp-Trap 2000 A4BQ series.
- 1800 A rated current.
- 600 V AC maximum voltage rating.
- 500 V DC maximum voltage rating.
- Class L rejection-style fuse construction.
- Four-second time delay at 500% rated current.
- Silver-plated copper blade terminals.
- Bolted mounting for secure industrial installation.
Reliable Protection for High-Power Distribution Systems
The Mersen A4BQ1800 limits excessive fault current before it can reach its maximum prospective value. By reducing short-circuit let-through current and energy, the fuse helps minimise damage to conductors, switchboards, transformers and other critical electrical distribution components.
When correctly coordinated, the A4BQ1800 provides a high level of protection for service entrance equipment and downstream circuits. Its time-delay operation allows normal equipment inrush currents to pass while responding reliably to sustained overloads and dangerous short-circuit conditions.
Typical Applications
- Industrial switchboards and distribution panels.
- Service entrance equipment.
- Main distribution and feeder circuits.
- Motor control centres.
- Transformer protection.
- Industrial disconnect switches.
- Heavy manufacturing and process equipment.
- Compatible high-current AC and DC systems.
Technical Specifications
Tick the specs you need, then view products that match.
| Current | 1800 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| Item number | A4BQ1800 | |
| Description | Fuse A4BQ - Class L - Time-Delay 600VAC 500VDC 1800A Blade Amp-Trap 2000® | |
| EAN/UPC Code | 782001930127 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 500 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 1800 A | |
| AC or DC | AC/DC | |
| Fuse Class | Class L | |
| Speed/Characteristic | Time Delay | |
| Mounting | Bolted | |
| AC Max I.R./Breaking Capacity | I1: 200 kA | |
| Connection/Terminal Material | Silver-Plated Copper | |
| Connection/Terminal Type | Blade | |
| Product Diameter | 88.9 mm | |
| Product Length | 273 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 3.9735 kg | |
| Sell Pack Width | 95.2 mm | |
| Sell Pack Length | 304.8 mm | |
| Sell Pack Height | 96.8 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 3.783 kg | |
| HS Code | 85361090 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4BQ1800 used for?
The Mersen A4BQ1800 protects high-current industrial power distribution systems, service entrance equipment, transformers, feeders and motor circuits against overloads and short circuits.
What is the current rating of the A4BQ1800?
The fuse has a rated current of 1800 A.
What voltage is the A4BQ1800 rated for?
The A4BQ1800 is rated for systems operating at up to 600 V AC or 500 V DC.
What is the interrupting rating of the A4BQ1800?
The Mersen A4BQ1800 has a maximum AC interrupting rating of 200 kA.
Why does the A4BQ1800 have a time delay?
Its four-second time delay at 500% rated current allows temporary motor, transformer and equipment inrush currents to pass without nuisance fuse operation.
How is the A4BQ1800 installed?
The fuse uses silver-plated copper blade terminals and bolted mounting. It must be installed in compatible Class L equipment with suitable voltage, current and interrupting ratings.
Trusted Industrial Circuit Protection
Mersen Amp-Trap 2000 Class L fuses are specified by electrical engineers, panel builders and industrial facilities for dependable protection of high-capacity electrical distribution systems.
