equipment, having to sacrifice operating time is far from trivial. Discussing the task at hand with

Rockwell Automation it turned out quickly that the pharmaceutical company in Arlesheim was looking for the performance delivered by an Allen- Bradley PowerFlex 755TR AC drive. “We had this extraordinary application

with custom-designed motors that could under no circumstances be damaged,” explains Dr Schaller. “The immense centrifugal forces demanded appropriate safety precautions. Seven sub-processes had to function both in a combined manner and independently. The centrifuge had to start up softly, brake in a controlled fashion and allow for the recovery of braking energy without interference,” he summarises. At Iscador, the AC drive – specifically a

Working for Iscador AG, the Invag AG was tasked with developing a drive solution for a high-speed centrifuge. These devices can only be found in two places worldwide: First, as part of an experimental research facility and second, for the manufacturing of pharmaceuticals


n this instance, the entire component range, from the water-cooled motor,

right up to the bearings, represented a special design for the production of the anthroposophic mistletoe drug, ISCADOR. Iscador AG is a pharmaceutics company

that supplies complementary medicine for integrative cancer treatment. In this context, the focus is on the healing power of the mistletoe. “The leaves, stems and berries of mistletoe are used for the production of our drug,” explains Dr. Gerhard Schaller, head of manufacturing and member of the executive management at Iscador. “We harvest once in the cold and once in the warm season, as evergreens display seasonal variations with regard to the active substances. The lectine concentration is at its highest in winter, and the amount of viscotoxins increases in summer. We concentrate on a specific mix of both.” The juice collected in winter is


continuously dosed in the center of a rotating disk, which exhibits a raised lip at its edge, and moves outwards as a thin film towards the outer rim due to centrifugal force. The summer juice, on the other hand, is added drop by drop at certain positions from a height of one meter. Both types of juice are then thoroughly mixed at the rim of the disk. “The 1m-diameter titanium disk rotates

at a speed of 10,000 RPM throughout the production process,” explains Christian Albisser, head of central services at Iscador. “This results in a rim speed of 1,885 kph and centrifugal forces that are 55,000 times greater than the force of gravity.” The power supply was subjected to

undesired feedback effects as soon as the facility entered the high-rpm-range. In some cases certain consumers even had to be shut down in order to ensure network stability. With regard to lab

Rockwell Automation www.rockwellauto

Thanks to the modernisation of the entire drive solution, spinning up the centrifuge has lost its impact on the power supply

200 kW IP21 model – functions as the central motor element for the production of the mistletoe drug. The motor control system must harmonise with the oil lubrication system on the engine mounting as well as the cooling unit and the pressurised air, vacuum and helium supply of the facility. The AC drive must adapt the rotational speed in accordance with the amount of helium available to flood the disc area. “At Iscador we had six minutes to spin up to 10,000 rpm. Then the titanium disk had to rotate at constant speed for two hours, with thermal generation and vibrations simultaneously kept within a very limited range,” describes Martin Neuenschwander, commercial engineer at Rockwell Automation. Simply ‘just’ delivering, installing and

powering up was definitely out of the question. Instead, the engineers from Invag and Rockwell Automation carefully approached the optimal parameter settings together with the customer on a step-by-step basis. The PowerFlex 755TR mitigates the

harmonics and therefore minimises the voltage distortion of the supply network. Spinning up the centrifuge no longer has a detrimental effect on the work going on in the lab, because all other devices can now remain in operation during the production phase. The energy consumption is also lower. “The power consumption during peak

operation has been reduced by 22 per cent. We now manufacture even more efficiently and without an impact on the rest of the building,” says Dr. Schaller.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40