The importance of energy efficiency to heavy industry
Capturing energy data at SKET Industriepark GmbH in Magdeburg
In addition to direct energy costs and effective capacity utilisation of power distribution systems and equipment, economic efficiency plays an important role at SKET Industriepark GmbH. In pursuit of continuous energy data capture, the company enlisted the support of Janitza electronics GmbH and HIT HIGH TECH Ingenieurgesellschaft mbH.
HIT HIGH TECH Ingenieurgesellschaft mbH with headquarters in Wilhelmshaven, was commissioned by SKET Industriepark GmbH (Magdeburg), a subsidiary of ENERCON in Aurich whose services include the main production of mechanical components for wind power plants (blades, towers, nacelles), to develop a system for standardised, low voltage-related billing of energy costs and for distribution of transformer power losses to corresponding cost centres.
Until now, it has only been possible to read off energy data from energy meters by hand. In order to optimise this time-consuming procedure, the energy meters have now been networked together in order to create an automated workflow.
As a result, a total of 77 measuring points at SKET Industriepark can now be queried electronically, with additional automatic monitoring of all key electrical parameters.
The shift to electronic data measurement and monitoring
With an existing Profibus fibre-optic ring being one of the largest load balancers on the site, there was little need for discussion about the type and nature of the data transmission. The only difficulty came from the relatively little space available in the distribution units, which meant that it was not possible to use every measuring device from the extensive range. In order to meet the limited spatial conditions, an especially compact measuring device had to be found for the individual outputs, and the UMG 103 universal measuring device from Janitza electronics GmbH was chosen. However, with an RS485/ Modbus interface, the UMG 103 was not entirely suitable owing to the need for data from the UMG 103s to be communicated over a Profibus connection. A solution was quickly found in Janitza‘s UMG 604EP device, installing it alongside the UMG 103. The UMG 604EP is a state-of-the-art measuring device with a sampling rate of 400 samples per period. In addition to an RS485 Modbus interface and RJ45 Ethernet connection, the UMG 604EP is also equipped with a Profibus interface.
In this setup, the UMG 103 operates as a data measuring point, capturing the data before transferring it to the UMG 604EP. The use of the UMG 604EP network analyser allows not only consumption data, but also key data relating to the currents, power and harmonics of the transformer stations to be displayed.
The UMG 604EP provides a range of features. In addition to reliable measurement, it is capable of simultaneous processing of 7 control programs.
For this, Janitza electronics GmbH has developed a special program (multitouch) for writing the variables of the slave measuring devices connected to the RS485 (in this case the UMG 103) to global variables in the UMG 604. Consequently, these devices can be used as a Profibus, Modbus/TCP or BACnet gateway.
Modbus Profibus gateway
The graphical programming makes it possible to establish a Modbus Profibus gateway. In the following examples, readouts are performed via Modbus slave measuring devices. The determined values are set on a Profibus profile (image 1). This program allows values from slave devices to be written to a Profibus profile via the gateway function, without a Profibus protocol.
The data can then be captured via the connected S7 PLC. As part of the project, Wilhelmshaven-based HIT used its considerable expertise to help display the approx. 2000 data points from the measuring devices in a superordinate control software application. This involved configuring the corresponding Profibus profiles for the individual measuring devices, which are processed cyclically by the PLC (image 2).
The power analyser is capable of managing up to 255 Profibus profiles (16 profiles in the configuration). Each Profibus profile can contain a maximum of 128 data bytes. The first data byte of the PLC‘s output range always contains the profile number of the Profibus profile requested by the power analyser. To request a Profibus profile, the profile number must be written to the first byte of the PLC‘s output range (image 3). All system variables and global variables can be individually scaled and converted into one of the following formats: 8, 16, 32 bit integer with and without sign, 32 or 64 bit float format (big or little endian). (Image 4, 5 and 6)
The use of UMG 103 measuring devices and UMG 604EP network analysers has helped to produce an energy analysis based on the data acquired through automatic measurement data capture. The specially developed control software provides a basis for clear documentation and management of all available energy data. A continuous exchange of data, permanent monitoring and continuous data recording provide for a transparent and generally comprehensible energy balance. This in turn allows for straightforward identification of sources of errors and timely improvements to individual systems. These measures together help to ensure that energy consumption and energy costs are kept permanently in focus.
Current overview of energy data
Basis for energy management systems in accordance with EN 50001
Monitoring of performance data of individual distribution units
Recording of events to improve system availability
Detailed display of various cost centres
Type/number of measuring devices
- 15 x UMG 604EP
- 62 x UMG103
- Profibus to UMG 604EP
- Modbus between UMG 604EP master and UMG 103 slave devices
- GridVis for power quality analysis
- Win CC for visualisation and billing
Janitza® electronics GmbH
Janitza electronics GmbH is a German company and has been active for 50 years in the manufacturing of systems for efficient power application, energy measurement and cost savings. As a globally renowned manufacturer of network monitoring and energy management systems, digital integrated measurement devices, power factor controllers and compensation systems, the company stands for the highest quality standards and innovations. Products are manufactured according to leading-edge expertise with state-of-the-art production technology. At Janitza, quality management is an ongoing managerial task (e.g. ISO 9001). Comprehensive know-how, competent consultancy and concept generation, right through to the commissioning of tailored solutions, ensure fulfilment of customer wishes and requirements.
SKET Industriepark GmbH
SKET Industriepark GmbH unites efficient production and innovative industrial service to form an extraordinary combination of German skill and expertise. Its core areas include complex machine and system engineering, heavy steel construction and the production and processing of components for wind power plants. Jointly, these make SKET Industriepark part of a new industrial culture in Magdeburg, dedicated to the manufacture of state-of-the-art systems for the exploitation of renewable energy. Companies with operations at SKET Industriepark benefit from wholly synergy-based collaboration.
HIT HIGH TECH Ingenieurgesellschaft mbH
HIT HIGH TECH Ingenieurgesellschaft mbH is an international medium-sized company with headquarters in Wilhelmshaven. This experienced and forward-looking company provides planning for building services, including state-of-the-art building and industry automation. The engineering firm is recognised for its competence and reliability, and plans projects in the fields of electrical engineering, heating, air-conditioning and sanitary systems with high technical standards to meet the exacting requirements of its customers.
Services also include the compilation of expert reports and testing in accordance with the stipulations of the Association of Insurers (VdS). In addition to professional, timely execution, the company also prepares complete documentation. A team of highly-qualified and highly-motivated employees is on hand to provide customers with a reliable and professional service. Its friendly and customer-focused approach is complemented by a flexible and a safety-conscious way of working.