AJT20 - 20 Amp Fuse

AJT20 - 20 Amp Fuse

The AJT20 Class J Time-Delay Fuse is built for your electrical systems that deal with normal startup surges but still need dependable overcurrent protection. Motors, transformers, compressors, and HVAC equipment often pull extra current for a short time during startup.

One of the biggest advantages of the AJT20 is its compact Class J design. It takes up less space than many traditional fuse types, making it a practical choice for crowded control panels and electrical equipment where space matters. Even with its smaller size, the fuse provides strong current-limiting protection that helps reduce the amount of fault energy passing through the circuit during a short circuit event. That can help you limit damage to wiring, controls, and connected equipment.

The built-in SmartSpot® visual indicator also makes maintenance easier by providing a quick way to identify when the fuse has opened. Instead of spending extra time troubleshooting, maintenance teams can locate the issue faster and get equipment back up and running with less delay.

Designed for commercial and industrial applications, the AJT20 is commonly used in motor control centers, HVAC systems, industrial machinery, transformers, feeder circuits, and branch circuits where reliable circuit protection is important day after day.

Key Features and Benefits

• Time-delay design helps prevent nuisance fuse openings during startup currents: Allows temporary inrush currents to pass without unnecessary interruptions.
• Current-limiting protection helps reduce damage during fault conditions: Helps minimize thermal and mechanical stress on connected electrical equipment.
• Compact Class J size helps save panel space: Fits well into installations where enclosure space is limited.
• SmartSpot® visual indicator allows quick fuse identification: Helps maintenance teams quickly locate opened fuses.
• High interrupting rating for demanding applications: Suitable for commercial and industrial high fault-current environments.
• Suitable for AC and DC systems: Compatible with a variety of electrical distribution systems.
• Ferrule-style construction supports secure installation: Helps provide dependable fit and electrical connection.
• Commonly used in commercial and industrial electrical systems: Designed for dependable operation in demanding environments.
  

Technical Specifications

• Catalog Number: AJT20
  
• Series: AJT – Class J – Time-Delay
  
• Fuse Type: Amp-Trap 2000®
  
• Ampere Rating: 20 Amps
  
• Voltage Rating (AC): 600 VAC
  
• Voltage Rating (DC): 400 VDC
  
• Frequency: 50/60 Hz
  
• Fuse Class: Class J
  
• Characteristic: Time Delay
  
• Interrupting Rating: 200 kA
  
• Mounting Type: Clip Mount
  
• Terminal Type: Ferrule
  
• Terminal Material: Tin-Plated Copper
  
• Indication System: SmartSpot® Visual Indicator
  
• Body Material: GMG
  
• Product Diameter: 20.7 mm
  
• Product Length: 57.2 mm
  
• Product Weight: 0.044 kg
  

Material Compliance and Certifications

• Industry Standards: The AJT20 fuse is part of Mersen’s Low Voltage UL/CSA fuse line and is designed for commercial and industrial electrical systems requiring dependable current-limiting overcurrent protection.
• Protection Requirements: It also supports IEC Type 2 “No Damage” protection requirements when properly coordinated within electrical systems.
  

Where It Works Best

• The AJT20 works well in HVAC equipment, motor control centers, industrial machinery, transformers, control panels, compressors, feeder circuits, and branch circuits where temporary startup surges are expected during normal operation. Its compact footprint and time-delay performance make it especially useful in systems where both space savings and reliable protection are important.