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MERSEN FUSE 600V 450A L TD FUSE A4BQ450
Robust Class L time-delay fuse with TA blade indicator, rated for 600VAC and 500VDC at 450A, featuring a 200 kA interrupting rating and bolted mounting.
£620.14
Why Choose the Mersen A4BQ450 Class L Time-Delay Fuse?
The Mersen A4BQ450 is a premium Class L time-delay fuse designed to provide reliable overcurrent and short-circuit protection for high-capacity industrial and commercial electrical systems. As part of the proven Mersen Amp-Trap 2000® A4BQ series, it delivers superior current-limiting performance for service entrance equipment, switchgear, feeder circuits and other critical power distribution applications.
Featuring advanced Amp-Trap 2000® current-limiting technology, the A4BQ450 helps minimise damaging fault energy while protecting downstream electrical equipment against high short-circuit currents. Its built-in 4-second time-delay characteristic at 500% of rated current allows motors, transformers and other inductive loads to start without nuisance fuse operation, helping maximise system reliability and uptime.
Rated at 450 A with 600 V AC and 500 V DC voltage ratings, the A4BQ450 is ideal for demanding industrial installations requiring dependable circuit protection, high interrupting capacity and compliance with Class L fuse standards.
Key Advantages
- Heavy-duty Class L time-delay fuse for industrial power distribution.
- 450 A current rating for high-capacity electrical systems.
- 600 V AC / 500 V DC voltage ratings.
- Advanced Amp-Trap 2000® current-limiting technology.
- 4-second time delay helps prevent nuisance operation during equipment start-up.
- Provides excellent protection for service entrance equipment, switchgear and feeder circuits.
Key Features
- Mersen Amp-Trap 2000® A4BQ series.
- 450 A ampere rating.
- 600 V AC / 500 V DC rated voltage.
- Class L time-delay fuse.
- Current-limiting design reduces let-through current and energy.
- 4-second minimum time delay at 500% rated current.
- Blade terminal construction.
- Suitable for service entrance, feeder and branch circuit protection.
Reliable Protection for Industrial Power Systems
The Mersen A4BQ450 is designed to protect industrial electrical systems from damaging overloads and severe short-circuit currents while allowing temporary inrush currents associated with motors, transformers and other inductive equipment. Its advanced current-limiting design reduces thermal and mechanical stress on downstream electrical components, helping extend equipment life and improve system reliability.
As part of the trusted Amp-Trap 2000® product family, the A4BQ450 is widely specified for industrial and commercial power distribution systems where dependable overcurrent protection and high interrupting performance are essential.
Typical Applications
- Service entrance equipment.
- Industrial switchgear and switchboards.
- Main electrical distribution systems.
- Feeder circuits.
- Motor control centres.
- Transformer protection.
- Commercial and industrial electrical installations.
Technical Specifications
Tick the specs you need, then view products that match.
| Fuse Indication | Visual indicator | |
|---|---|---|
| Current | 450 A | |
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| Item number | A4BQ450-TA | |
| Description | Fuse A4BQ - Class L - Time-Delay 600VAC 500VDC 450A Blade TA Indicator Amp-Trap 2000® | |
| EAN/UPC Code | 782001293956 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 500 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 450 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 | |
| Indication System | Yes | |
| Indication System Type | TA Indicator | |
| Connection/Terminal Material | Silver-Plated Copper | |
| Connection/Terminal Type | Blade | |
| Product Diameter | 50.8 mm | |
| Product Length | 219.2 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 1.3336 kg | |
| Sell Pack Width | 63.5 mm | |
| Sell Pack Length | 222.2 mm | |
| Sell Pack Height | 60.5 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 1.2701 kg | |
| HS Code | 85361090 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4BQ450 used for?
It provides overcurrent and short-circuit protection for industrial power distribution systems, service entrance equipment and feeder circuits.
What is the current rating of the A4BQ450?
The fuse has a 450 A current rating.
What voltage is the A4BQ450 rated for?
The fuse is rated for 600 V AC and 500 V DC operation.
Why does the fuse include a time-delay feature?
The integrated time-delay allows temporary motor and transformer inrush currents to pass without nuisance operation while maintaining reliable fault protection.
Where is the A4BQ450 typically installed?
It is commonly installed in service entrance equipment, switchgear, feeder circuits and industrial power distribution systems requiring Class L fuse protection.
Trusted for Industrial Circuit Protection
Mersen Amp-Trap 2000® Class L fuses are trusted worldwide by electrical engineers and industrial facilities for delivering dependable overcurrent protection, superior current limitation and reliable performance in critical power distribution systems.
