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Rotor Field Winding Test

  1. To check for grounds, attach ohmmeter leads to shaft and slip ring (each ring in turn). If reading is not infinity, replace rotor.
  2. To test for open field, attach ohmmeter leads to each slip ring. Resistance should measure about 2.4-2.8 ohms on 12SI series, or 1.7-2.1 ohms on 17SI series. If not, replace rotor.
Fig 1: Rotor Bench Test For Open or Short Circuit
G10029
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