Berlin-based drive manufacturer Menzel has delivered a customised replacement drive that covers two different motors to an Albanian cement plant.

After the drive was extensively tested in Menzel’s load test field in the presence of the customer, the motor was shipped in April 2014. The plant operator required a spare motor for two existing high voltage slip ring motors: the main drive for the raw mill and the drive for the raw mill fan.

While these systems have similar performance ratings (3,000 and 3500kW, respectively) and are both designed for a rated voltage of 6000V, they also feature considerable differences. The motors have different sizes, shaft measurements, and rotational directions. The location of the terminal boxes is not identical, either.

As a solution, Menzel designed a slip ring motor with two different shaft ends, terminal boxes that are connected in parallel for stator and rotor connection on both sides, and suitable adapter plates and frames to adjust the motor sizes and mounting dimensions. This was facilitated by the high power density and the resulting compact dimensions of Menzel’s MEBSSL motor series – the spare motor is based on a size 630 model. With a performance of 3500kW and a speed of 990 min-1, it can replace either slip ring motor. "The customer thus benefits from an ideal balance between plant reliability and cost efficiency," Menzel said in a statement.