Nishi-san’s tips on medium and high voltage motor and generator maintenance are back, now with live broadcasts and open participant Q&A. Watch and participate in this online event with lots of technical content and the wisdom of more than 70 years of Nishi-san who knows how to take care of your equipment. In this meeting we address the subject of Electrical Tests: Low Voltage Winding x Medium/High Voltage. It will be relevant information for you to assess and make the best decisions for your maintenance planning. In this live will be presented basic concepts about voltage classification and constructive characteristics. And the list of standard electrical tests for windings according to voltage classification:

Voltage classification of generators/motors:

  • Low Voltage: Round or Enameled Wire / Voltage Class: 127/220/380/440/760 V.
  • Medium Voltage: Rectangular Wire / Coils or Bars / Voltage class: 2,3/3,4/4,16/6,6/6,9 kV.
  • High Voltage: Rectangular Wire / Coils or Bars / Voltage Class: 13,8/16,5/18,0 kV or higher.

Standardized offline electrical testing:

  • Insulation Resistance (IEEE-43);
  • Polarization Index (IEEE-43);
  • Ohmic Resistance (IEEE-118);
  • HypotAC/DC (IEEE-4 / IEEE-95);
  • Step VoltageDC (IEEE-95);
  • Surge Test (IEEE-522);
  • Off-line Partial Discharges (IEEE-1434 / IEC6034-27-1);
  • Delta Tangent (IEEE-286);
  • Capacitance (IEC 60034-27-30);
  • Corona in darkroom) (IEEE-1799).

Turn on the subtitles in your language and watch below in Nishi’s Youtube channel the live recording and learn more about the definition and application of each electrical test according to voltage level and how it is essential for a good diagnosis of the condition of the motor/generator winding.

Take part in upcoming live opportunities to ask questions and make comments directly with an expert on rotating electrical machines.

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