Benshaw White Paper: Ball Mill Positioning with the H2 Series VFD

This white paper from Benshaw explores how applying a low voltage H2 Series Variable Frequency Drive (VFD) significantly enhances ball mill positioning operations. The solution simplifies maintenance, improves inching precision, increases speed by up to 30 times, and reduces mechanical wear and downtime — delivering a more reliable, cost-efficient approach for large-scale synchronous motor applications.

Key Points

  • Industry Application: Ball mills are widely used in cement and mineral processing to grind clinker and other materials into fine powder.
  • Innovative Solution: Benshaw’s 480VAC H2 Series VFD was applied for positioning a 4160V, 3500HP synchronous motor-driven ball mill.
  • System Benefits: Eliminates DC contactors and cam switches, reducing space requirements, maintenance needs, and equipment stress.
  • Operational Impact: Enhances reliability, reduces downtime, saves energy, and improves overall plant productivity.
  • Positioning Challenge: Traditional DC contactor systems made mill positioning slow, imprecise, and prone to mechanical wear.
  • Efficiency Gains: The AC VFD increased inching speed from 0.18 Hz to 6 Hz — a 30x improvement — drastically cutting maintenance time.
  • Integrated Motor Control: The VFD can be multiplexed between multiple mills and paired with Benshaw’s medium voltage solid-state starters for turnkey solutions.
  • Proven Expertise: Benshaw has over 30 years of experience and an installed base exceeding 100,000HP in ball mill motor controls.