The automation specialist LÜTZE in Weinstadt has expanded its portfolio of modern motor supply cables to include much improved low-capacity properties.

The new LÜTZE motor supply cables were also optimised in terms of energy efficiency. The advantage over conventional cables, such as cables with PVC insulation and high capacitance are significant: Firstly, the cables absorb much less charging current and therefore do not heat up as much.  As a result, the current is supplied to the motor more eficiently. Secondly, much longer cable paths can now be planned. LÜTZE offers special low-capacity cables for fixed and mobile installation, for use with frequency drive motors and for use in C-tracks.

Innovative cable materials and material combinations

In terms of its Low-Capacity cables, LÜTZE primarily focuses on two material components: XLPE and PP. As an insulation material, XLPE (this is an English abbreviation for networked polyethylene) offers a very low capacitance and excellent electrical properties, as well as a high dielectric strength. XLPE naturally prevents undesirable transfer losses and blocks corona discharging. This makes XLPE the ideal premium insulation for LÜTZE, in particular for applications with high voltage peaks and longer cable paths. In the case of permanently installed cables, LÜTZE also uses insulation made of polypropylene (PP) that has a low dielectric constant.

LÜTZE Low-capacity motor supply cables in practice.

LÜTZE has an extensive program of low-capacity motor supply cables to cover all industrial applications.

•    Variable Frequency Drive cables serve as power cables between the speed-controlled drive system and the speed-controlled motor. They are usually permanently installed in cable racks and ducts. We recommend e.g. LÜTZE SILFLEX B XLPE (C) PVC 0.6/1kV.
•    Alternatively, LÜTZE supplies cables with polypropylene insulation that are also low-capacitance, e.g. the LÜTZE SILFLEX M (C) PVC Servo.
•    LÜTZE supplies motor cables, such as the SUPERFLEX PLUS M (C) PUR SERVO, for mobile applications and for use in power cable chains.

Background information

Capacitance and power loss

Every cable has a certain amount of ‘power loss’ or capacitance. Depending on the structure and material quality, the capacitance may be higher or lower. The cable capacitance is primarily influenced by the dielectric constant of the material, and also by the structure and thickness of the insulation on the cable. The lower the dielectric constant, the lower the cable capacitance. The capacitance should be as low as possible for power supply cables to motors with high loads. Low capacitance therefore means that the cable acts less like a capacitor, generates less heat and transfers the energy with less loss, i.e. more efficiently.