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Stator Tester optimizes quality control in the manufacture of electric motors

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In the course of certain production and annealing processes changes take place in the electromagnetic properties of electrical steel which often lead to deterioration in the quality of the material. Many manufacturers are faced with the problem of testing magnetic properties, particularly hysteresis loss, before and during the production process. With its newly developed " C 510 Stator" BROCKHAUS has put onto the market an instrument which allows the stators to be tested before the winding. This saves time and costs and makes quality control even more reliable. Up to now it has not been possible to carry out non-destructive inspection of electric steel/stators on arrival of the material. The first inspection of all stators/electric motors does not take place until after completion of manufacture, e.g. in a final "Surge test" (test under voltage). Faults which are discovered at this stage in production will by then already have caused a high investment in material and personnel.

Unforeseen problems through rationalization in production

Nowadays more and more importance is attached to quality control in the manufacture of stators. This is due partly to the increasing pressure with regard to price which affects all manufacturers of electric motors. Buyers are trying to extend their circle of suppliers for materials. At the same time they must however ensure that the quality of the material is always maintained at the same level. Furthermore the situation is not being made any easier by a change which is being introduced into the manufacturing process for stators: the production sequence used to be stamping, annealing and then packetizing; but now, in order to save time and costs, the production process is changing over to packetizing after stamping and before the annealing process. However this rationalization step does involve risks. Should one of the sheets in the package be of inferior quality then neither the finished stator nor the complete electric motor can be used.

Until now those who were involved in processing or trading with these products could rely on the quality certificates provided by manufacturers of electrical steel and therefore only carried out random checks on the material. However the modifications in production described above have brought about fundamental changes. Ongoing quality testing has therefore become imperative for processors of electrical steel, especially for those involved in the production of electric motors.

Fully automatic stator measuring station guarantees product quality "on-line"

The fully automatic stator measuring station "C 510 Stator" can be integrated easily into the production line (on-line) for the manufacture of stators or electric motors. Manual operation is of course also possible when measuring single parts. The size of the stators is of no consequence - the "C 510 Stator" measures all the stators before final winding and thereby ensures constant product quality. Prior to inspection the test winding is applied to the stator fully automatically by means of an electro-pneumatic contact system. The actual testing process is completed in 2 seconds. If the measuring process is interrupted manually an integrated light barrier discontinues the measurement. With the "C 510 Stator" the time-consuming manual preparation of samples with primary and secondary windings is no longer necessary. Once the data have been obtained they are displayed interactively on a monitor and stored. So continuous and complete documentation of performance data is guaranteed. The software for the "C510 Stator" is based on the "MPG-Expert- Software" developed by BROCKHAUS and has a completely new user interface for PC- controlled measuring systems for determination of the soft magnetic properties of electrical steel. MPG-Expert operates under Windows 98/ME/NT/2000/XP and makes use of all Windows options for the flexible application of well-proven MPG-Expert functions. The "C 510 Stator" is supplied with a monitor in a 19"-16 HE- cabinet.