Electronic Braking for Knelson Concentrators

Our client needed a solution to reduce the stopping time of their processing plant’s Knelson Concentrators to increase production. As the existing concentrators were started using soft starters, it could not be stopped rapidly during each stop sequence due to the high inertia of the concentrator. The concentrator’s stopping time was circa 3-4 minutes, which was significantly impacting their production capacity and causing delays between cycles.  The solution also had to be cost effective and implemented with minimal interruption to production.

PulseTech, as an electrical engineering firm was engaged to solve this problem and successfully reduced the stopping time of the concentrators from 3 mins to only 30 seconds by retrofitting an electronic DC brake into the existing starter panel. Design considerations included equipment selection, protection, thermal capacity of motors, interfacing of retrofit with existing starter drives, additional feedback from DC braking unit and interfacing with plant DCS. Needless to say, our client was very satisfied with the outcome.

Our scope of work included design, preparation of drawings, project management, supply, installation supervision and commissioning of equipment that includes:


  • 4 x 75kW and 1 x 30kW soft starter/DC brake systems for high inertia concentrators 

  • Integrated DC brakes and controls into existing soft starter system

  • Manufactured and supplied soft starter/DC brake panels

  • Installed and commissioned with minimal disruption to production