A4BY1800 - 1800Amp Fuse Description
A4BY1800 - 1800Amp Fuse
Meet the Mersen A4BY1800 Amp-Trap® Class L Time-Delay Fuse—your go-to solution for keeping high-current electrical systems safe without compromising performance. Rated for 1800 amps, this fuse is built to handle heavy-duty service entrance equipment, feeder circuits, and circuit breakers. Its smart time-delay design lets it ride through harmless surges, like motor startups or temporary spikes, so you don’t get unnecessary trips—but it acts fast when a real fault occurs, protecting your equipment and minimizing downtime.
If you want protection that’s precise, dependable, and built for real-world performance, the A4BY1800 has you covered.
Key Features and Benefits
- Time-delay design passes harmless surges without tripping
- 1800A rating for heavy-duty service entrance and feeder circuits
- Rated for 600VAC / 300VDC applications
- High 200kA AC interrupting capacity for fault clearing
- Silver-plated copper blade terminals for reliable connections
- Clear markings simplify identification and servicing
- Bolt-mounted installation for secure connections
Technical Specifications
- Catalog Number: A4BY1800
- Series: A4BY – Class L – Time-Delay
- Fuse Class: Class L
- Ampere Rating: 1800A
- Voltage Rating: 600VAC / 300VDC
- Frequency: 50/60 Hz
- Speed/Characteristic: Time-Delay
- Mounting: Bolted
- Connection Type: Blade
- Connection Material: Silver-Plated Copper
- AC Max Interrupting Rating: 200kA
- Body Material: GMG (Glass Melamine)
- Diameter: 88.9 mm
- Length: 273 mm
- Product Weight: 3.8374 kg
Material Compliance and Certifications
- RoHS Compliant
- Meets UL/CSA standards for low-voltage fuses
Where It Works Best
- The A4BY1800 shines in applications where high-current protection and surge tolerance are essential:
- Service entrance panels
- Feeder circuits and distribution systems
- Industrial machinery protection
- Commercial power distribution
- Circuit breakers in critical infrastructure
- Fast, reliable, and built to last, the Mersen A4BY1800 is a fuse that keeps your electrical systems running safely and smoothly—exactly what you need in demanding industrial or commercial environments.
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Specifications
- Width:2.75
- Depth:2.75
- Height:10.75
- Amperes:1800
- A.I.C. Rating & Volts:200 kA @ 600 V.AC
- Type:A4BY
- Additional Notes:Knife-Blade Style, Non-Indicating, Time-Delay, current-limiting Class L Fuse
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You may return unused items within 30 days of delivery for a full refund.
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