A4BY4000 - 4000Amp Fuse Description
A4BY4000 - 4000Amp Fuse
When it comes to high-current electrical protection, the Mersen A4BY4000 Amp-Trap® Class L Time-Delay Fuse delivers performance you can trust. Rated at 4000 amps, this fuse is ideal for service entrance equipment, feeder circuits, and large circuit breakers. Its time-delay design lets harmless surges, like motor startups or brief spikes, pass through without tripping—so your systems stay running smoothly—but it reacts instantly to real faults, keeping equipment safe and downtime minimal.
Installation is simple, thanks to silver-plated copper blade terminals and a bolt-mounted design. The tough glass melamine (GMG) body holds up under continuous heavy loads, while a 200kA AC interrupting capacity ensures even the most demanding industrial or commercial systems are protected. Clear markings make it easy to identify and replace, giving you peace of mind and making maintenance faster and simpler.
Key Features and Benefits
- Time-delay design handles harmless surges without tripping
- 4000A rating for high-current service entrances and feeder circuits
- Rated for 600VAC / 300VDC applications
- 200kA AC interrupting capacity for fast fault clearing
- Silver-plated copper blade terminals for reliable connections
- Durable GMG (glass melamine) body for long-lasting stability
- Continuous-duty operation at full amp rating
- Easy-to-read markings for maintenance and replacement
- Bolt-mounted installation ensures a secure fit
Technical Specifications
- Catalog Number: A4BY4000
- Series: A4BY – Class L – Time-Delay
- Fuse Class: Class L
- Ampere Rating: 4000A
- 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)
- Product Diameter: 146 mm
- Product Length: 273 mm
- Product Weight: 11.4305 kg
Material Compliance and Certifications
- RoHS Compliant
- UL/CSA approved for low-voltage applications
- Meets industry standards for industrial and commercial electrical protection
Where It Works Best
- Service entrance panels
- Feeder circuits and distribution systems
- Industrial machinery protection
- Commercial power systems
- Critical circuit breakers in essential infrastructure
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Specifications
- Width:4.75
- Depth:4.75
- Height:10.75
- Amperes:4000
- 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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