User Documentation
Weidmüller t Technical information
Lars Brakemeier, January 2020, Page: 1/3
Weidmüller Interface GmbH & Co. KG | Klingenbergstraße 18 | D-32758 Detmold
Application area of wire end ferrules with plastic collar
Dear ladies and gentleman,
the purpose of this technical information is to inform about the intended use of wire end ferrules with
plastic collar.
Wire end ferrules with plastic collar offer additional ease of insertion due to the conical shape that is
integrated in the inner diameter of the collar. Additionally, avoids that the rough insulation edges of the
conductor getting caught when connecting at the clamping point. The different color codes offer a visual
aid for cross-section identification.
The requirements for wire end ferrules are defined in DIN 46228. Therefore, this standard is decisive for
basic conditions and key parameters.
Contrary to the common opinion the plastic collar of the wire end ferrule does not offer kink protection,
unlike insulated cable lugs. Neither is the plastic collar of the ferrule a mechanical insulation support and
therefore should not be stressed by excessive pulling or bending. Additionally to this, during the
assembly, all relevant standards must always be complied with. According to DIN VDE 0298-300
conductors must only be installed in certain bending radius. For instance a PVC insulated wire with
conductor diameter ≤ 20 mm should have a bend radius of no less than 6 times that of the conductor
diameter. In practice this means that no significant pull should stress the plastic collar of the wire end
ferrule!
Img. 1: exemplary description for clarification of bending radius
Example calculation a 2.5mm² (AWG20), according to installation method, has a recommended bend
radius of 6D. With a conductor diameter of 2.57mm this leads to: 6D = 6 x 2,57mm = 15,4 mm