The Haßberg Clinics are a network of general hospitals in the Haßberge district, located in Haßfurt and Ebern. During a modernization of the low-voltage distribution systems, energy data acquisition and residual current monitoring from PQ Plus were also installed. These systems create energy transparency, enable energy savings, simplify maintenance, and allow for electricity billing for tenants.
Image: Haßberg Clinics
The largest hospital of the Haßberg Clinics [1] is the hospital in Haßfurt, founded in 1945. Continuous additions and expansions have gradually led to a capacity expansion to the current 150 beds. The range of services includes anesthesia, acute geriatrics with a certified geriatric trauma center, general surgery with a vascular surgery section, orthopedics and trauma surgery, internal medicine, cardiology and gastroenterology, as well as gynecology and obstetrics. In Haßfurt, approximately 7,000 inpatients and almost 9,000 outpatients are cared for annually by approximately 450 employees.
The Ebern Hospital of the Haßberg Clinics looks back on over 100 years of history and currently offers a capacity of 50 beds on an internal medicine ward, which also includes an intermediate care ward and palliative medicine with a SAPV outpatient unit. In Ebern, approximately 250 inpatients and around 1,300 outpatients are cared for annually by approximately 60 employees.
Modernization of Low-Voltage Distribution Systems
The modernization of the low-voltage distribution systems in Haßberg and Ebern began in 2020. This project also included the implementation of energy data acquisition, residual current monitoring, and an energy management system. The data would also enable energy cost billing for tenants and service providers, such as the canteen. The planning office and the operator were impressed by the PQ Plus hardware and software. PQ Plus's product portfolio focuses on power quality monitoring according to DIN EN 50160, RCM/residual current monitoring, consumption and power measurement, MID-compliant metering, and third-party metering. The company's employees advise users and interested parties on selecting the right measurement technology for their projects, provide installation support, and carry out commissioning.
The UMD 98 LB universal panel-mounted meters record all energy data.
Image: PQ Plus
Analyze and optimize energy consumption
Energy meters and energy management software complement each other perfectly for monitoring and improving the energy efficiency and safety of building electrical infrastructures. Energy meters record energy consumption in real time at various points in the building. The energy management software collects this data and presents it in clear dashboards that allow users to monitor energy consumption and identify trends. By analyzing the data from the energy meters, the energy management software can identify potential savings. Furthermore, it can be configured to trigger alarms when energy consumption increases unexpectedly or deviates outside predefined limits. Jens Schübel, Technical Director at PQ Plus GmbH, explains: "Our energy measuring devices offer a wide range of functions and options to more than meet the requirements of energy management. From cost-effective energy meters and universal measuring devices with high accuracy, to our compact and modular system for a wide range of central measurements, to our power quality analyzers with high sampling rates and additional measurement inputs for residual current measurements, we cover all applications and requirements." Thanks to the various interfaces and diverse protocols, such as Modbus, M-Bus, MQTT, SNMP, and Bacnet IP, the data can be easily integrated into the PQ Plus software and third-party systems via various methods.
Software for Meaningful Data Analysis
The Envis Web software forms the basis for optimizing available energy. The recording and analysis of all relevant energy is automated. This database makes it possible to quickly identify potential savings, initiate the necessary measures, and monitor success. The Envis Web dashboard interface can be freely configured, offering each user a customized view of energy flows within the company. The load profile analysis visualizes a continuous characteristic curve of the measured data. Typically, 15-minute active power measurements are used as the basis. The graph shows the proportion of time a certain power is demanded over a selected total period. This allows opportunities to be identified to reduce power peaks and thus lower energy costs. Reducing the base load also offers potential savings.
Envis Web allows you to create customized, user-friendly dashboards. These provide data analysis of key metrics at a glance.
Image: PQ Plus
Networked Hardware
Approximately 15 UMD98 LB universal panel-mounted measuring devices are used at the Haßberg Clinics. The UMD 98 is a powerful panel-mounted measuring device that replaces all analog measuring devices. It measures 3/4-phase current and voltage in four-quadrant operation in Class 0.2, thus measuring energy in Class 0.5s, as well as all common network variables, such as harmonics up to the 50th harmonic. The device is connected via current transformers with N/5 A and N/1 A. The UMD98 has two analog inputs for RCM measurements. It can be used in 230/400 V TN-S systems. The device can be accessed via the Ethernet interface and the front-panel mini-USB port. This allows internet protocols to be read and PLC and building management systems to be easily connected. Digital inputs/outputs and a serial RS-485 interface are also integrated.
Recording energy flows and residual currents
Approximately 45 MMI current measurement modules record energy flows and residual currents in the various areas of the Haßberg Clinics. The MMI 12 was developed for remote monitoring of energy consumption. It is designed for mounting on a DIN rail or mounting plate and does not have a local display. This concept makes it suitable for a wide range of applications in energy technology and smart grids, building automation and individual production processes, as well as for remote infrastructure monitoring and automatic load management. The module measures twelve currents via single- or three-phase current transformers. It enables the measurement of basic electrical parameters of up to four three-phase branch circuits. It is connected via the local bus to an MMU 3 or MMB 700 system, which is used for voltage measurements, the concentration of measured data, and access to a higher-level system. Up to five MMI-12 modules can be operated on a single bus, enabling compact measurements on up to 20 three-phase branch circuits or 60 currents. The MMI 12 RCM variant is specifically designed for residual current measurement.
The MMI current measurement modules record energy flows and residual currents in the various areas of the Haßberg Clinics.
Image: Haßberg Clinics/Frank Hußlein
Continuous Residual Current Measurement
In electrical installations, unforeseen insulation damage can be detected in a timely manner using continuous residual current measurement. This allows for early retesting in the case of elevated residual current values. This usually prevents an uncontrolled shutdown of the system. A welcome side effect is that insulation testing according to DGUV Regulation 3 can be omitted. This is documented in DIN VDE 0105-100/A1 (VDE 0105-100/A1) [5]. It states: "If a circuit is continuously monitored by a residual current monitoring device according to DIN 62020 (VDE 0663) ... and these monitoring devices are functioning properly, insulation resistance measurement can be omitted." Conventional insulation measurement is often quite complex. In some cases, system components such as frequency converters or switching power supplies must be disconnected because the sensitive semiconductor components can be damaged by the test voltages.
The current transformers allow for a detailed analysis of the electrical system.
Image: Haßberg-Kliniken/Frank Hußlein
Third-party metering enables energy billing
The data from the CMD EEG-104CLP load profile meters enables energy costs to be billed using third-party metering. The devices are PTB-A 20.1, PTB-A 50.7, and MID B+D approved. The 15-minute load profile memory has a storage depth of over three years. The data can be visualized via the integrated web server. Networking is via the integrated TCP/IP interface with Modbus TCP. A logbook documents events relevant to calibration law and configuration changes. A large, illuminated, and easy-to-read LCD displays the data on-site. The ability to use third-party metering was an important criterion for the Haßberg Clinics when selecting their energy management system. When an end consumer forwards electricity quantities to another end consumer—i.e., to a third party—this is referred to as third-party metering. A distinction between these third-party consumption and the company's own consumption becomes necessary if the primary consumer takes advantage of energy-related privileges for electricity consumption, such as a reduced electricity tax on grid purchases. The reduced surcharges, taxes, and duties apply only to the primary consumer and not to third parties. Third-party consumption is not always as clearly identifiable within a company as it is with rented office space or company housing. Often, kitchens, vending machines, or coffee machines are located on company premises and are operated by third parties. Examples include radio masts and charging stations for electric cars.
Conclusion
"With the PQ Plus system we have installed, we can precisely analyze and track energy flows. During the certification according to DIN EN 50001 approximately three years ago, our measurement concept and the devices used also impressed the certifying body," reports Frank Hußlein, Technical Director at the Haßberg Clinics. Significant savings potential has already been identified and utilized. Since the system offers the possibility of recording water and gas consumption via interfaces in addition to conventional measurements, F. Hußlein intends to further expand this area in the near future. "The residual current measurement currently in use facilitates monitoring and early detection in the low-voltage mains distribution system (LVD). Damage can be detected early, thus preventing uncontrolled shutdowns. The elimination of the insulation testing requirement in the low-voltage mains distribution system (LVD) is another advantage," explains F. Hußlein.
Frank Hußlein, Technical Director at Haßberg-Kliniken: "The support provided by PQ Plus staff before, during, and after the project gives no cause for criticism."
Image: Haßberg-Kliniken/Frank Hußlein
