🔍 Key Concepts

• Insulation condition vs. temperature in electric motors • What a megger (megohmmeter) reading actually tells you about insulation • Common symptoms of dirty vs. damaged components: brushes, bearings, windings

💭 Think About

• Which symptom is most directly related to the heat created by poor insulation on the windings? • Does high insulation resistance (shown by a megger) mean insulation is dirty or in good condition? • Which options could be caused by other mechanical issues (like imbalance or worn bearings) rather than dirty winding insulation?

✅ Before You Answer

• Be clear on what a high megger reading means: high resistance (good) vs. low resistance (bad). • Identify which choice points to a problem that would increase current and cause overheating in the windings. • Eliminate options that are more clearly tied to mechanical problems (vibration) or brush/commutator issues, not winding insulation.