Mill Spotting Drive Application Experience

The plant was having problems with performance and reliability of an old contactor based spotting drive system on their grinding mill. The options were to apply a new version of the old contactor technology, a soft starter solution, or apply a new LV AC drive based spotting control system. This paper discusses the electrical and mechanical evaluation leading up to the decision to proceed with this new application of a LV AC drive solution. The paper will review the customer´s options and decision processes. It will cover some of the practical challenges of the installation process and how these were overcome. The operation of the end result will be discussed regarding improved performance and controllability.