Procedure

  • The 100% cdf power for wire and grid resistors is initially calculated using the following formula:
  • Average braking power / overload factor (wire / grid resistor)
  • Refer to the diagrams for the overload factor (wire and grid resistor) with a cyclic duration factor (cdf) of 6%.
  • Results:
  • 100% cdf power for wire resistors: 685 W.
  • 100% cdf power for grid resistors: 856 W.
  • The maximum braking resistance value is 72 Ω for a peak braking power of 13 kW when using a MC07B..-5A3 (AC 400/500 V unit) (see peak braking power table).
  • Select the appropriate braking resistor from the assignment tables with the following points:
    • Maximum braking resistance value
    • MOVITRAC® B unit used
  • Result when using MC07B0110-5A3, for example: BW039-12