Frictionmeter / RK - LD

Friction coefficient measuring unit RK – LD

The frictionmeter ‘RK-LD’ has been developed for calculating the friction coefficient µd according to
DIN specification EN 60851-3 method B.

The measuring unit is used in order to check the influence of different finish on the operating characteristic of enamel copper wire or other flexible materials with diameters from 0,1 to 0,8 mm.

When the friction coefficient µd of enamel copper wire is known you will be able to have an effect on the packing density of a motor armature coil during winding.


The unit is composed of three 19” plug-in modules integrated in a 19” housing. The upper plug-in module includes a measuring device with a tensile force sensor. In the middle plug-in module there are two adjustable brakes. A rewinder is in the lower drawer. The measuring unit is complete with the Tensometric software RK-LD-WIN. This software controls the frictionmeter and calculates the result of a measurement.


Measuring principle:

The wire coming from a reel or barrel is guided over an adjustable brake. From there it is running over a base plate, and thereafter deflected twice so the wire will be running once more over this plate parallel to the first flow. Then it will be rewound on an electric driven reel. A weight plate which is smoothed with a predefined surface roughness will be put on both parallel wires running over the base plate. This weight plate is static and connected with a high precision sensor. During the wire movement under the weight plate a force - which is depending from the friction of the wire – is measured by the tensile force sensor. This force is a measure for the friction coefficient µ.