Rittal AS 4051.541 insulated ferrules 0.75 mm² (AWG 18) copper core, polypropylene collar, length 8 mm, diameter 3.4 mm, pack of 4000

Rittal AS 4051.541 insulated ferrules are designed for consistent and reliable wire terminations of 0.75 mm² (AWG 18) conductors. Each ferrule combines a copper crimp barrel with a polypropylene (PP) insulated collar to ensure good electrical contact, mechanical stability and insulation at the connection point. The ferrules measure 8 mm in length and 3.4 mm in collar diameter and are supplied in a pack of 4000 for high-volume installation and repetitive wiring tasks in control panels, terminal blocks and other electrical assemblies.

Advantages

These insulated ferrules provide a defined crimp area that improves conductor insertion and compression, reducing stray strands and improving contact reliability. The copper core ensures low electrical resistance and corrosion resistance at the crimped joint, while the polypropylene collar protects against short circuits and assists with insulation in confined terminal spaces. A large pack quantity supports continuous work without frequent reordering and helps maintain consistent installation standards across multiple terminations.

Suitable for

• Terminating single-core copper conductors of 0.75 mm² (AWG 18)
• Control panels, switchgear and distribution blocks
• Industrial wiring, machine cabling and factory automation
• Electrical maintenance, repair and repetitive assembly tasks

When it may not be suitable

These ferrules are intended specifically for solid or stranded copper conductors with a cross-section of 0.75 mm² (AWG 18). They are not appropriate for significantly larger or smaller conductor sizes, aluminium conductors, or where specialized high-temperature or chemical-resistant insulation is required. Use of improper crimp tools or incorrect crimping technique can compromise connection quality.

Key specifications

• Conductor cross-section: 0.75 mm² (AWG 18)
• Barrel material: copper
• Insulation collar material: polypropylene (PP)
• Overall length: 8 mm
• Collar outer diameter: 3.4 mm
• Pack quantity: 4000 pieces

How to use

Strip the conductor to the recommended length so that the bare conductor fits fully into the copper barrel. Insert the conductor into the ferrule until the insulation meets the polypropylene collar. Use a suitably sized ferrule crimping tool to apply a single, clean crimp at the barrel, ensuring the strands are compressed evenly. After crimping, check that the ferrule is securely attached and that the insulated collar sits flush against the conductor insulation before inserting into the terminal block or screw connection.

What to consider before purchase

• Verify conductor cross-section compatibility (0.75 mm² / AWG 18).
• Confirm material preferences for barrel (copper) and collar (polypropylene) suit the application environment.
• Ensure you have the correct ferrule crimping tool for this size to achieve reliable crimps.
• Assess whether the bulk pack quantity (4000) matches your storage and consumption needs.

Usage recommendations

Use a dedicated crimping tool sized for 0.75 mm² ferrules and perform a pull test on a sample termination after crimping. Store the ferrules in a dry environment to avoid contamination and ensure consistent installation quality by training personnel on correct stripping and crimping technique.