Ferrule Rittal AS 4051.605 — insulated copper ferrules 2.5 mm² (10 mm length), pack of 3000, blue

Rittal AS 4051.605 insulated copper ferrules are designed to provide secure, low-resistance terminations for 2.5 mm² (AWG 14) stranded conductors. Each ferrule features a tin-plated copper tube and a polypropylene insulating collar in blue, with a tube length of 10 mm and an outer collar diameter of 4.2 mm. Supplied in a pack of 3000, these ferrules are intended for professional electrical installation tasks such as control cabinets, terminal blocks and industrial wiring where reproducible crimped connections are required.

Advantages

These insulated ferrules offer consistent mechanical and electrical joints by enclosing stranded conductors in a rigid metal sleeve, which reduces fraying and ensures reliable contact in screw or spring-type terminals. The polypropylene collar provides electrical insulation and strain relief at the entry point, improving handling during insertion and preventing conductor damage. The tin plating enhances corrosion resistance and long-term conductivity in industrial environments.

Suitable for

• Terminating 2.5 mm² (AWG 14) stranded copper wires
• Wiring in control cabinets and distribution panels
• Connections to terminal blocks, relays and contactors
• Industrial automation and machine wiring where repeated assembly is expected

When it may not be suitable

These ferrules are sized specifically for 2.5 mm² (AWG 14) stranded conductors; they will not fit smaller or larger cross-sections properly and may compromise connection quality if used incorrectly. They are intended for copper conductors and are not suitable for direct termination of solid conductors or aluminum conductors without appropriate preparation or suitable alternatives.

Key specifications

• Conductor cross-section: 2.5 mm² (AWG 14)
• Tube material: tin-plated copper
• Insulation material: polypropylene collar (blue)
• Tube length: 10 mm
• Outer collar diameter: 4.2 mm
• Pack quantity: 3000 pieces

How to use

Strip the stranded conductor to the appropriate length so the bare strands fully enter the copper tube. Insert the conductor into the ferrule until the insulation collar sits flush with the wire insulation. Use a calibrated crimping tool or ferrule crimper sized for 2.5 mm² ferrules to make a single, firm crimp ensuring the sleeve is uniformly compressed around the strands. After crimping, check that the ferrule is secure and that no strands are protruding before inserting into the terminal and tightening the terminal screw to the manufacturer's torque specification.

What to consider before purchase

• Verify conductor type and cross-section: suitable for stranded copper 2.5 mm² (AWG 14)
• Confirm required tube length (10 mm) and collar diameter (4.2 mm) are compatible with your terminals
• Ensure availability of a compatible crimping tool for insulated ferrules
• Determine pack size (3000 pcs) matches your usage to avoid excess or shortage

Usage recommendations

Use with a dedicated ferrule crimping tool matched to 2.5 mm² insulated ferrules for consistent results. Store the pack in a dry, dust-free environment and handle ferrules with clean hands or gloves to avoid contamination of contact surfaces. For repeatable and safe electrical connections, follow applicable wiring standards and terminal manufacturer torque values.