If the voltmeter on a running motor indicates no measurable voltage between L1 and T1 terminals of the contactor, what does this suggest?

When a voltmeter on a running motor shows no measurable voltage between the L1 and T1 terminals of the contactor, it indicates that there is an issue preventing voltage from reaching the motor at that point. In this scenario, the correct interpretation would be that the contacts within the contactor are likely not providing a proper connection, as good clean contacts would exhibit measurable voltage across those terminals.

If the contacts were functioning correctly and were clean, there would be a measurable voltage present when the motor is running, indicating that the electrical circuit is complete and allowing power to flow. The failure to measure voltage suggests that either the contacts are not closing properly or there is a serious issue in the control circuit that prevents the voltage from reaching the terminal.

In other options, while a faulty motor or poor wiring could potentially lead to a loss of voltage, they would typically present additional symptoms or indicators elsewhere in the system. A capacitor failure, particularly in a single-phase motor, would often lead to start or run issues rather than just a total lack of voltage reading at the contactor. Thus, the lack of measurable voltage is primarily indicative of an issue directly related to the contactor's contacts rather than to the motor itself or other wiring concerns.