Question 485Electricity & Electronics - QMED

70% to pass

As shown in figure "B" of the illustration, with a digital multimeter set up as an ohmmeter, what set of readings would be consistent with an open in a phase of the single circuit, delta-connected stator windings as shown? Illustration EL-0201

Diagram for USCG Electrical QMED: As shown in figure "B" of the illustration, with a digital multimeter set up as...

AT1 to T2: "1.8 ohms"; T2 to T3: "OL ohms"; T3 to T1: "1.8 ohms"

BT1 to T2: "1.8 ohms"; T2 to T3: "3.6 ohms"; T3 to T1: "1.8 ohms"

CT1 to T2: "3.6 ohms"; T2 to T3: "1.8 ohms"; T3 to T1: "1.8 ohms"

DT1 to T2: "OL ohms"; T2 to T3: "1.8 ohms"; T3 to T1: "1.8 ohms"

AI Explanation

The correct answer is C: T1 to T2: "3.6 ohms"; T2 to T3: "1.8 ohms"; T3 to T1: "1.8 ohms". In a delta-connected stator winding, an open in one phase will result in the other two phases appearing in series, leading to a total resistance of 3.6 ohms between the two healthy phases (T1 to T2). The resistance between the healthy phase and the open phase (T2 to T3 and T3 to T1) will be half of the total, or 1.8 ohms. The other options are incorrect because they do not represent the expected resistance readings for an open in a single phase of a delta-connected stator winding.