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MERSEN FUSE L TD FUSE 600V 900A A4BQ A4BQ900
Dependable Class L time-delay fuse rated for 900A, 600VAC/500VDC with high interrupting capacity of 200 kA. Suitable for industrial and commercial circuit protection.
£738.88
Why Choose the Mersen A4BQ900 Class L Time-Delay Fuse?
The Mersen A4BQ900 is a premium Class L time-delay fuse designed to provide outstanding overcurrent and short-circuit protection for industrial and commercial power distribution systems. As part of the renowned Mersen Amp-Trap 2000® A4BQ series, it is engineered for service entrance equipment, switchgear, feeder circuits and other high-capacity applications where dependable circuit protection is essential.
Amp-Trap 2000® A4BQ fuses deliver up to 20% greater current limitation than conventional Class L fuses, reducing short-circuit let-through current and energy to better protect downstream equipment. Their integrated 4-second time-delay characteristic at 500% of rated current allows harmless inrush currents from motors, transformers and other inductive loads to pass without nuisance operation.
With a rated current of 900 A, voltage ratings of 600 V AC and 500 V DC, and exceptional interrupting capability, the A4BQ900 provides reliable protection for demanding industrial electrical systems while helping minimise equipment damage during fault conditions.
Key Advantages
- Premium Class L time-delay fuse for industrial power distribution.
- 900 A current rating for high-capacity electrical systems.
- 600 V AC / 500 V DC voltage ratings.
- Amp-Trap 2000® technology provides up to 20% greater current limitation.
- 4-second time delay prevents nuisance operation during motor and transformer start-up.
- 300 kA AC self-certified interrupting capability with UL-witnessed testing.
Key Features
- Mersen Amp-Trap 2000® A4BQ series.
- 900 A ampere rating.
- 600 V AC / 500 V DC rated voltage.
- Class L current-limiting time-delay fuse.
- 4-second minimum time delay at 500% rated current.
- 200 kA AC interrupting rating.
- 100 kA DC interrupting rating.
- 300 kA AC self-certified performance with UL-witnessed testing.
- Pure silver fuse links for low let-through current.
- Fibreglass body for dimensional stability.
- High-grade silica filler for rapid arc quenching.
- Rejection-style Class L design prevents incorrect replacement.
- RoHS compliant.
Advanced Protection for Industrial Power Distribution
The Mersen A4BQ900 is engineered to minimise the effects of severe overloads and short-circuit faults by limiting the current and energy reaching downstream electrical equipment. This helps reduce thermal and mechanical stress on switchgear, busbars, conductors and other critical system components.
Its integrated time-delay characteristic allows temporary motor and transformer inrush currents to pass without nuisance operation while maintaining dependable protection against sustained overloads and fault currents. This combination of current limitation and time-delay performance makes the A4BQ900 ideal for demanding industrial environments.
Typical Applications
- Service entrance equipment.
- Industrial switchgear and switchboards.
- Main electrical distribution systems.
- High-current feeder circuits.
- Large motor protection.
- Transformer protection.
- Circuit breaker back-up protection.
- UPS DC links and battery disconnect systems.
- Heavy industrial and commercial facilities.
Technical Specifications
Tick the specs you need, then view products that match.
| Current | 900 A | |
|---|---|---|
| Voltage | 600 V | |
| Fuse Type | UL class | |
| Fuse Class | Time delay | |
| Item number | A4BQ900 | |
| Description | Fuse A4BQ - Class L - Time-Delay 600VAC 500VDC 900A Blade Amp-Trap 2000® | |
| EAN/UPC Code | 782001930059 | |
| Rated voltage AC UL | 600 V | |
| Rated voltage DC UL | 500 V | |
| Frequency (Hz) | 50/60 Hz | |
| Ampere Rating | 900 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 | 63.5 mm | |
| Product Length | 273 mm | |
| Sell Pack Quantity | 1 EA | |
| Sell Pack Weight | 2.0412 kg | |
| Sell Pack Width | 88.9 mm | |
| Sell Pack Length | 279.4 mm | |
| Sell Pack Height | 82.6 mm | |
| Product group | Low Voltage UL/CSA Fuses | |
| Body/Insulating Material | GMG | |
| Product Weight | 1.9459 kg | |
| HS Code | 85361090 | |
| Country of Manufacture | Mexico |
Frequently Asked Questions
What is the Mersen A4BQ900 used for?
The A4BQ900 provides overcurrent and short-circuit protection for service entrance equipment, feeder circuits, switchgear and high-capacity industrial power distribution systems.
What is the current rating of the A4BQ900?
The fuse has a rated current of 900 A.
What voltage ratings does the A4BQ900 support?
The fuse is rated for 600 V AC and 500 V DC.
What is the interrupting rating of the A4BQ900?
The fuse provides a standard interrupting rating of 200 kA AC and 100 kA DC, with 300 kA AC self-certified performance verified through UL-witnessed testing.
Why does the A4BQ900 include a time-delay characteristic?
The 4-second time delay allows temporary motor and transformer inrush currents to pass without nuisance operation while maintaining reliable protection against overloads and short circuits.
Trusted for High-Capacity Circuit Protection
Mersen Amp-Trap 2000® Class L fuses are trusted by electrical engineers and industrial facilities worldwide for delivering exceptional current limitation, high interrupting performance and dependable protection of critical power distribution systems.
