Bringing Ethernet from the office to the plant field requires a number of enhancements, the most important of which is real-time capability. Depending on the application, a marketable Industrial Ethernet must be able to handle safety applications or the entire spectrum of drive technology, including clock-synchronous motion control with cycle times of less than one millisecond. This is achieved by a clever division of the protocols via the OSI layer model. Many solutions have been developed in this way. One of the most common is the open PROFINET standard, which also offers a high level of investment protection. Existing fieldbus systems such as Profibus DP, Profibus PA, AS-Interface and Interbus can be integrated without modifying the existing field devices.

PROFINET already saves costs during installation, engineering and commissioning. Later on, the operator benefits from the easy expandability and high availability of autonomously operating subsystems. Accordingly, PROFINET is represented in all applications in mechanical and plant engineering: In the automotive industry, the paper industry, plastics processing, conveyor technology, the food industry and process engineering. It makes sense to also use this communication structure for machine-related energy data acquisition. For this purpose, Janitza has developed a PROFINET specialist based on the tried-and-tested UMG 96 devices: The UMG 96RM-PN – a measurement device that is far more than a standard version with a flange-mounted PROFINET interface.

The UMG 96RM-PN has two PROFINET IO-IRT-compliant Ethernet interfaces and an integrated switch. The structure of the fieldbus technology is presented in accordance with the standard using familiar line topologies. Parameterization and configuration can be carried out entirely via the Step 7® environment, for example. All measured values are mapped directly in the process data channel of the PLC. Its digital inputs and outputs can be used via both Modbus and PROFINET. Two analog inputs are available for 0-50 mA or temperature detection. A separate 5A current measurement channel can monitor the neutral conductor, for example.

All relevant measured variables and communication parameters can be displayed on the device’s own homepage. A REST interface enables measured values and configuration parameters to be queried via the HTTP interface. One highlight is the integrated residual current measurement (RCM), which can be used to detect incipient insulation faults at an early stage. This increases system availability and reduces the risk of fire.

For some years now, the classic planning model and the technology of electrical energy supply have been changing due to many external circumstances. The requirements for more efficient grids play just as important a role as the constantly increasing feed-in power from renewable energies. Most of these influences affect the low-voltage grid. Critical operating states and overloads can occur there, as the classically planned grids were not designed for this.

Local network substations are increasingly becoming intelligent nodes: They take on tasks ranging from pure measurement, fault location, fault detection and power quality analysis to complete remote control or even automation. Especially when retrofitting existing local network stations, the following framework conditions must be taken into account.

The UMG 96RM-PN is PROFINET-certified and suitable for use with PROFIenergy. A PROFINET certificate certifies standard-compliant behavior in accordance with IEC 61158 within a PROFINET network and thus ensures a high quality standard.

PROFIenergy is a profile for energy management in production plants based on PROFINET. This allows energy consumption within the system to be controlled via open and standardized commands. With the use of PROFIenergy, external, hard-wired systems are no longer required.