Kollmorgen has developed a module that stores braking energy from a servo amplifier and can use it later for acceleration or to operate machines more reliably in areas prone to fluctuating power supplies. The capacitor-based ESM (energy saving module) also allows axes to be driven to a predefined position in the event of a network failure, reducing the risk of accidents and costly repairs.

The module is designed to be used with Kollmorgen`s S300 or S700 servo amplifiers. It captures energy that would normally be wasted as heat via a braking resistor. By re-using this energy later, it cuts energy consumption. In the case of printing and packaging applications, where braking occurs frequently, the energy savings can amount to 70%. Heat in the switching cabinet is also reduced and there is a possibility of operating more machines from a power supply.

In the event of short voltage dips or power cuts, the module can bridge the gap. By smoothing out supply instabilities in precision applications such as milling or grinding, it can improve manufacturing quality.

The status and charge of the ESM can be determined via a fieldbus. Energy meters can show the savings achieved for each motor, thus helping to identify mechanisms, such as gearboxes, consuming large amounts of energy. The charge/discharge cycles can range from 200ms to several minutes.