Power distribution: In safe hands

The Saarland University Medical Center is growing closer together: All the clinics for Internal Medicine are to be joined in one centralized building complex. A genuine mammoth project, in which the integrated power supply must be guaranteed 100 percent – because in extreme situations, it saves lives.

In a wooded area south of Homburg, over one hundred clinic buildings are scattered on a space of 200 hectares (nearly 500 acres). They belong to the Saarland University Medical Center (UKS). With the new construction project, IMED (internal medicine), launched in 2009, all that is now going to change: In the future, all the clinics for Internal Medicine will be clustered in one large building complex.

 

The "UKS Future Project" was kicked off back in 2009, with the aim of designing a more efficient infrastructure and spatial organization for the hospital, which first opened in 1909 and has undergone several expansions. Within the scope of the project, mainly the clinics for Internal Medicine are being consolidated in one building. The new building project consists of two construction phases: In 2015, the first part was opened, and the second part is scheduled to be put into operation in the year 2018. When it is completed, the IMED department will be in a centralized location. Among other departments, the entire building will then house the modern emergency room facility, the heart catheter rooms, the bone marrow transplant (BMT) station, part of the clinic for diagnostic and interventional radiology, laboratory areas along with the helicopter landing pad on the roof.

 

But in addition to offering the advantage of more rapid care of patients, the move is also accompanied by numerous challenges. One of them was setting up an absolutely reliable power supply – and doing so during ongoing operations. The medical center placed this task in the hands of Siemens: It opted for a unified technical solution encompassing both medium voltage and low voltage – in short: Totally Integrated Power.

The previous power supply was already provided by Siemens. We have had absolutely positive experiences with the performance and quality of the products. That is why we are delighted that Siemens was also awarded the tender for this major new construction project. We know what we are getting.
Rudi Veith, Head of Electrical Engineering at UKS

All-round protection in power supplies

The overall project of the centralized IMED building is especially voluminous because all conceivable disciplines, right down to the pneumatic tube system, had to be involved in the planning. As usual, prior to start of construction, there was a European-wide tender, which clearly outlined the scope of deliverables according to DIN standards: The required systems comply with the highest standards in terms of thermal loads and short-circuit capacity, thus guaranteeing a high level of supply reliability. For example, in case of failure, the general power supply (GPS) is required to be able to switch over to safety power supply (SPS) in less than 15 seconds, and the power supply to operating rooms is not allowed to be interrupted at any time.

 

Because Siemens was able to comply with these and other requirements with especially effective technical and commercial solutions, the main contractor R+S solutions GmbH awarded the company the contract for installation of medium-voltage equipment and busbars. In the low-voltage area, Scholl Energie- und Steuerungstechnik, a Sivacon Technology Partner of Siemens, installed the relevant products. "The previous power supply was already provided by Siemens. We have had positive experiences with the performance and quality of the products. That is why we are delighted that Siemens was also awarded the tender for this major new construction project. We know what we are getting!", added Rudi Veith, Head of Electrical Engineering at UKS. To meet the requirements of the controlgear assembly with design verification, the solution involves an integrated system, from medium voltage right down to the last circuit outlet, which is extremely reliable and only requires low maintenance.

Over 1,200 meters of busbars

For the network calculation, technology partner, Scholl, utilized the Simaris planning tool from Siemens. It assists electrical designers in quickly and efficiently planning even the most sophisticated systems. In the case of UKS, it even saved plenty of money. Because initially there were plans for an outgoing cable solution from the transformers. The calculations with Simaris, however, showed that Sivacon 8PS busbar trunking systems are an economical and space-saving alternative: Instead of 84 thick cables, only six busbars have to be installed. They now lead from the transformers to the four low-voltage distribution boards and from there to three building main distribution boards each. "With cables, there would not have been sufficient space. But also in terms of fire load, the busbars are safer than cables. In addition, they can be easily routed around corners, which is advantageous if the phases otherwise have to be unwound through junction units", said Dirk Steding, project manager with R+S. 

 

In order to ensure the supply of power to the hospital at all times, there are already three SPS busbars alongside the three GPS busbars coming off the transformers. They are equipped with fire-resistant Promat boards and thus conform to Fire Protection Class F90. In other words: In case of fire, the Promat board will withstand fire for at least 90 minutes. If one adds the busbar meters of the GPS and SPS together, it amounts to over 1,200 meters – that is a genuine superlative even in the dimensions of a major project.

 

From the low-voltage distrubtion boards, the main nodes lead to the safety power supply. Here, three diesel generators guarantee the continuous operation of the IMED. They can only maintain emergency supply, so that the medically necessary socket outlets are active and half the lighting remains in operation. The switchboard system provides for easy and integrated power distribution, and the highest level of safety for persons and systems; this also applies to the system cubicles of the three building distribution systems: One part of them is equipped with a switchover device for the medical area and runs through a so-called Isolé Terre network (IT). In the event of a fault, e.g. an insulation fault or a defective cable, the circuit is not shut down immediately. This enables operations or examinations to be completed beforehand – in an emergency, this saves lives. 

2018-02-02

Picture credits: W. Geyer/Siemens AG

With roughly 50,000 in-patients and some 200,000 outpatients annually, the Saarland University Medical Center (UKS) is the largest hospital in the small German state. As a university medical center, it handles numerous tasks that go far above and beyond the services of traditional hospital care. No less than ten intensive care units and 203 beds for intensive care patients provide for their treatment. In the neonatal intensive care station, newborn children in critical condition receive medical care. The UKS is also a center for bone marrow, stem cell, kidney, liver and lung transplants.

Especially relevant for the power supply were the DIN VDE 0660 standards, and DIN VDE 0107 for locations for medical use. According to DIN VDE 0660, in terms of electrical power supply, the hospital required a controlgear assembly with design verification. Relevant systems comply with the highest standards with respect to thermal and short circuit loads – thus guaranteeing a high level of supply security. Above all, in sensitive installations such as hospitals or data centers, that is why the use of systems with design verification is required. DIN VDE 0107 requires, for example, that in case of failure, the general power supply (GPS) shall be able to switch over to safety power supply (SPS) in less than 15 seconds, and the power supply to operating rooms, for example, shall not be allowed to be interrupted at any time. 

With the installation of a completely new medium- and low-voltage electrical power supply for the new IMED in the Saarland University Medical Center in Homburg, the necessary standards for reliable operation were able to be met. All in all, the installation encompassed one 8DJH MV switchgear, four Geafol cast-resin transformers, over 1,200 meters of LX busbars, 64 S8 Sivacon fields, 50 Sivacon 8MF1 system cubicles with, and some 70 system cubicles without switchover for medical premises. The result was an standardized and technically integrated power distribution solution according to the Totally Integrated Power Concept (TIP) from Siemens. 

Subscribe to our Newsletter

Stay up to date at all times: everything you need to know about electrification, automation, and digitalization.

Related Topics