ADLER EF3 EV Fuse 350–450 A for 250-V DC Systems

The ADLER EF3 is a compact, screw-in high-current DC fuse. It was developed to protect high-performance battery, charging, and battery management systems in electric and hybrid vehicles.

The ADLER EF3 series is available with various rated currents and voltage ratings. On this product page, you can choose from 350, 400, and 450 A at 250 V DC. For lower rated currents, separate versions are available with 150, 200, 250, and 300 A at 200 V DC.

Advantages of the ADLER EF3 EV fuse

• High DC fault current protection: Breaking capacity of up to 50 kA at 250 V DC.
• Suitable current ratings: Available on this product page in 350, 400, or 450 A.
• Expanded EF3 product line: Separate 200-V DC versions cover rated currents from 150 to 300 A.
• Compact dimensions: All three 250-V variants feature the same design.
• For cyclic loads: Designed to meet the requirements of electric vehicle and battery systems.
• Screw-type connection: The fuse is mounted using M8 screw connections.
• Traceability: According to the manufacturer, each fuse is marked with a QR code.

Available fuse ratings

The following rated currents for 250 V DC are available on this product page:

• 350 A
• 400 A
• 450 A

For applications with lower rated currents, the ADLER-EF3 series also offers fuses rated at 150, 200, 250, and 300 A at 200 V DC. Due to the different rated voltages and designs, these variants are listed on a separate product page.

Dimensions

The variants offered here with 350, 400, and 450 A have the same main dimensions:

Open the ADLER EF3 manufacturer’s data sheet

Suitable Applications

The ADLER EF3 was developed to protect high-performance battery, charging, and management systems in electric and hybrid vehicles. It is suitable for DC power paths where high operating currents and high potential short-circuit currents may occur.

Use in other mobile or stationary battery systems requires that the rated voltage, operating current, potential short-circuit current, time-current characteristic, and thermal conditions be properly verified. For applications up to 300 A, separate EF3 versions are available with ratings of 150, 200, 250, and 300 A at 200 V DC.

Selection and Installation

The appropriate fuse rating is not selected based solely on the normal operating current. The wire cross-section, load peaks, possible short-circuit current, ambient temperature, and the time-current characteristic must also be taken into account.

The EF3 is mounted using M8 screw connections. The manufacturer recommends a tightening torque of 12 ± 1 Nm. Refer to the current data sheet for complete installation and operating conditions.

Conclusion

The ADLER EF3 offers a compact solution for protecting high-power DC systems. On this product page, you can choose between 350, 400, and 450 A for 250-V DC applications. For lower rated currents, separate EF3 models are available with 150, 200, 250, and 300 A at 200 V DC.

Frequently Asked Questions About the ADLER EF3 EV Fuse

• What fuse ratings are available within the ADLER EF3 series?

  
  

  This product page offers variants rated at 350, 400, and 450 A at 250 V DC. In addition, separate EF3 models rated at 150, 200, 250, and 300 A at 200 V DC are available.

• What are the dimensions of the 250-V models?

  
  

  The variants offered here are 79 ± 1 mm long, 24 ± 1 mm high, and 32.3 ± 1 mm wide. The 200-V versions have a different, narrower design.

• Is a fuse holder included?

  
  

  The EF3 is the fuse insert. Whether a holder or additional connection hardware is included depends on the specific offer and scope of delivery.

• How do you determine the correct fuse rating?

  
  

  The determining factors are operating current, wire gauge, DC voltage, load peaks, potential short-circuit current, and the time-current characteristic curve. The design should be performed by a qualified professional.