UL Certified Crimped Wire Contacts

Ensure the longevity and quality of your electrical connections with wire end ferrules.

What is a wire-end ferrule?

The classic definition of a wire-end ferrule is a tinned copper sleeve, which is placed onto the end of the wire where it is crimped.

In other words, wire-end ferrules are used to insert the conductor into the connection or terminal compartment, protecting the fine strands of a multi-stranded wire and providing a gas-tight connection that prevents air or gasses (that lead to corrosion) to permeate.

Laboratory tests have proven that the use of ferrules can extend contact lifetime by preventing an increase in resistance and temperature, which can lead to short-circuits and/or failures.

Evidence in support of the prolonged contact lifetime, in addition to a more complete list of benefits, can be found in Weidmuller’s white paper entitled, “Ferrules: Your Best Insurance against Costly Connection Failure”.


Weidmuller announced that their? single conductor, wire-end ferrules with insulating “collar” are now certified by Underwriters Laboratories (UL), in accordance with UL standard 486A. This new approval, in addition to the existing CSA-US, DIN/VDE and VG certifications, allows customers greater access to global projects with stringent requirements to standards. The certified products are wire-end ferrules with insulating plastic collars for cross-sections ranging from 0.25mm2 to 50.0mm2 (AWG 26-1), with the exception of 35.0mm2 (AWG 2). All three ferrule color codes (used for visual identification); the Weidmuller, DIN, and “other” color codes, have passed the UL testing process and are listed in the UL Certifications Directory under file “Weidmuller - E354986”.

Complying with UL recommendations for ferrule crimping, the ferrules were tested and certified only after being crimped to a wire using Weidmuller hand tools and automatic wire processing machines. Therefore, the UL certification is valid only if the wire-end ferrules are processed with Weidmuller tools. The hand held tools utilized during the testing process were the PZ 4, PZ 6/5, PZ 3, PZ 6 Roto, and the PZ 16 for wire-end ferrules with plastic collars. Weidmuller’s automated wire-processing machines included the “Crimpfix” series of strippers and crimpers, the PowerStripper machines, and the CA 100 stripper and crimper.

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