Weidmüller and the crimp connection: wire-end ferrule UL certified

Weidmüller's crimped, insulated wire-end ferrules have now been granted UL certification - in addition to existing CSA-US, DIN/VDE and VG certification. The connection as a whole has been certified - not the individual components. Consequently, UL - Underwriters Laboratories -certified the system, meaning the wire-end ferrules together with the hand tools or automatic crimping machines used. This certification enables Weidmüller to increase the already high quality of its customers' products and exploit more markets in the NAFTA region (North America, Canada and Mexico). The products certified are wire-end ferrules with plastic collars in single packages for cross-sections ranging from 0.25mm2 to 50 mm2 (AWG 26-1) - with the exception of 35 mm² (AWG 2) - together with the corresponding hand tools and automatic strippers and crimpers. UL certification not only opens opportunities in North America and Canada to export-oriented companies, but the now certified, solderless connections with crimped wire-end ferrules also offer significant competitive and quality advantages for European and Asian markets. UL certification is valid only if the wire-end ferrules are processed with Weidmüller hand tools or automatic crimping machines contained in the list of tools.

Weidmüller has received vitally important worldwide certification for a crimped wire-end ferrule for the North American and Canadian region: not the individual components have been certified in accordance with UL 486A, but rather the connection as a whole. UL - Underwriters Laboratories - certified the system, which means the wire-end ferrules together with the hand tools and automatic strippers and crimpers used for the crimping process. The hand held tools utilized are the types PZ4, PZ 6/5, PZ3, PZ6 roto, PZ16 for wire-end ferrules with plastic collars as well as automatic Crimpex series strippers and crimpers as well as the automatic stripper and crimper CA 100.

UL approval applies to all insulated wire-end ferrules belonging to the cross-section range 0.25-50 mm2 (AWG 26-1) - excluding the following 35 mm2 (AWG 2) cross-section version: insulated wire-end ferrules sold in bulk form.

The classic 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 without it splitting. Tinning finely stranded wire ends does not afford protection against splitting, because the tin solder or the tinned wire conductor begins to yield under the pressure of the clamping screw. That is not the case when crimping: crimping represents a reliable, permanent electrical and mechanical connection between the wire conductor and the crimp contact; however, it is imperative that the wire conductor (cross-section) and crimping tool are designed to harmonize seamlessly. The wire ends fitted precisely with wire-end ferrules do not break off even when subjected to vibration loads.

In comparison with non-insulated ferrules, wire-end ferrules with plastic collars offer an enhanced level of electrical safety as well as mechanical stability; moreover, standardized colour coded plastic ensures wire conductor cross-sections are easily identifiable. Users are able to choose between the DIN colour code and Weidmüller's colour code. Wire-end conductors with plastic collars provide a flawless, gastight connection between the wire conductor and the ferrule. The twin wire-end ferrule is a sleeve with plastic collar into which two cables are fed simultaneously.

Crimped connections have proven themselves for years in thousands of millions of connections, a fact borne out by the constant electrical and mechanical values. Although it is true plastic was already UL approved, approval had still to be given to the wire-end ferrule as a whole. Now, however, approval for the system comprising wire-end ferrules, hand tools and strippers and crimpers as a whole means there is no obstacle left to worldwide acceptance. For export-oriented companies that means the lifting of trade and import restrictions in force to date; the UL certificate for the NAFTA (North American, Canadian and Mexican) region opens up market opportunities across the globe.

Weidmüller stands prepared with a comprehensive assortment: this includes wire-end ferrules (to DIN 46228, Paragraphs 1 and 4), with and without plastic collars for nominal cross-sections ranging from 0.14 mm2 to 50 mm2, crimp sets and special tools to strippers and crimpers through to wire-end ferrule boxes as well as boxes with coloured empty box inserts.

Source: Weidmüller Interface GmbH & Co. KG