Smart savings in automated systems
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MAKING MODERN LIVING POSSIBLE Smart savings in automated systems Select the right drive components and cut costs

Cut costs, conserve resources and protect the environment Energy prices have been increasing for many years, stimulating the desire to reduce energy consumption in industrial, mercantile and commercial applications. If this can be achieved, users can keep their operating costs constant or even reduce them, despite rising prices. Mechanical engineers and plant engineers can achieve competitive advantages by reducing the energy consumption of their facilities, with a corresponding reduction in energy costs. In addition to purely commercial reasons, there are social reasons – climate change –...

Quick, easy and inexpensive Our objective must be to achieve significant energy savings in both new and existing systems and machines. As a rule, the first thing that operators as well as mechanical engineers and system builders want are measures that can be implemented easily, quickly and, above all, inexpensively. Smart savings There is potential for saving energy in almost all areas. Whether building automation, conveyor systems or chemical processes, the difficulty lies in identifying potential and in finding the most cost-effective way in which to exploit it. When taking action to...

Savings, but not at any price Concentrating on action which is cost-effective and sensible Concentrating on action which is cost-effective and sensible A considerable amount of energy can be saved by implementing speed control on electric motors. So that such action achieves the required results, users and system builders have to take a number of important points into account. Estimating potential savings Regardless of whether a machine or system is new or existing, operators need to start by ascertaining the equipment’s “current state”. This includes calculating the energy consumption,...

Calculating prevailing energy consumption The time during which prevailing energy consumption can be calculated is determined by the application. In the case of defined technical processes, reliable consumption data is usually available after a number of full process sequences have been completed. Evaluating the consumption profile of applications which depend upon climatic conditions is more complex. The required delivery rate of a waste water pump, for example, is directly linked to prevailing rainfall levels. Testing applications with variable load torque In the case of applications with...

Motors: Potential for savings and future development Energy-efficient three-phase induction motors have been available in Europe since 1998. Classification has taken the form of efficiency classes eff1 to eff3. This voluntary agreement is being superseded by the international standard IEC 60034-30. There is massive potential with regard to the choice of gear type. Helical gears and bevel gears are, as a rule, much more efficient than worm gears. Operators who choose to use equally compact bevel gears as an alternative to worm gears will initially face higher investment costs. Geared motors...

Speed control: High potential – quick to implement When carrying but the necessary investigations, in addition to the costs incurred for procurement, conversion and energy, of course operators also need to consider maintenance and replacement motor concepts. Implementing speed control on load machines often brings with it energy benefits with which can be seen directly on users’ electricity bills. The advantages of using speed control include: Daily running hours Energy savings The extent of the energy-saving potential varies dependent upon the load’s torque characteristics. In the case of...

Constant torque applications Today there are already many instances of frequency converters being used for speed control in conveying systems. They optimise energy consumption depending on the load to be transported and the required speed. Savings in energy can be achieved directly if the speed can be reduced at constant load. It is often the case that the quantity of goods to be transported on a conveyor is not constant. Adapting the speed of the belt to the quantity of goods to be transported not only enables those goods to be processed without interruption, but also leads to a reduction...

Variable load torque applications power required and average part-load operation is too great, systems should be cascaded. It is often the case that investments pay for themselves relatively quickly when existing systems are converted, too. variable load torques are concerned. Reducing the speed generates a cubic reduction in energy requirements. This significant potential for savings makes all applications with variable torque characteristic ideal candidates for the implementation of energysaving measures. Variable torque applications often involve pumps and fans. However, a distinction...

Particulars of fans, pumps and compressors Swirl flaps, throttles or three-way valves are often used on most pumps or fans to regulate the pressure or volumetric flow of an application. If a centrifugal pump is controlled using a throttle valve, throttling moves the machine’s working point along the pump characteristic. The reduction in energy requirement achieved is minimal compared with the pump’s nominal operating point. If a pump is speed-controlled , the operating point moves along the system characteristic. The energy requirement is reduced by the power of three in comparison to...

Consider the power losses Close inspection saves hard cash At first glance a comparison of efficiency rates does not suggest any real difference between different devices. Devices with identical power and identical efficiency often exhibit different losses. The frequency converter efficiency is calculated from the ratio between power output and power input. It is usually expressed as a rounded percentage, i.e. without decimal places. In the worst-case scenario, therefore, converters with the same efficiency rate will differ by at least 1%. In order to be able to compare the efficiency of...