🔍 Key Concepts
• Delta-connected three-phase stator windings and how terminals T1, T2, T3 relate to each phase
• Meaning of a digital multimeter reading "OL" (over limit) versus a finite low resistance value when checking continuity
• How an open-circuited phase or a shorted phase would change resistance readings between each pair of terminals (T1–T2, T2–T3, T3–T1)
💭 Think About
• If two terminals show "OL" between them, what does that tell you about the continuity of the winding path between those two points?
• If one pair of terminals shows a normal low resistance while the other two pairs show "OL", which phase (A, B, or C) must still be intact, and what must be wrong with the remaining phases?
• In a healthy three-phase winding, what should the resistance readings between all three terminal pairs look like compared to each other?
✅ Before You Answer
• Be clear on which physical winding is associated with each labeled terminal (Phase A with T1, Phase B with T2, Phase C with T3).
• Verify what resistance you would measure between each pair of terminals if one phase were open versus if one phase were shorted.
• Confirm that a reading of "OL" means no continuity (open circuit), while a small ohm value indicates an intact winding path between those two terminals.