The video provides a comprehensive guide on performing a single-phase rotor test on a three-phase squirrel cage motor to check for open rotor bars. It begins with an introduction to the test's purpose and the importance of ensuring the stator winding is free from grounds, shorts, or opens by conducting preliminary tests such as insulation resistance, surge, and lead-to-lead resistance tests. The video then details the identification and setup of the necessary test instruments, including a single-phase power supply, digital voltmeter, and clamp-on amp meter.

The procedure involves correctly connecting the stator for the test, applying single-phase voltage, and measuring the maximum and minimum amperage during the test. By rotating the motor shaft manually and monitoring the current with a clamp-on amp meter, viewers can note the highest and lowest current values. The video explains how to calculate the test current variation and interpret the results to determine if the rotor has open bars. If the current deviation exceeds 3%, it indicates a probable open rotor bar.

Safety is emphasized throughout the video, with instructions on wearing proper protective equipment and ensuring all electrical connections are secure and isolated. The video also covers the safe disconnection of stator leads after the test and the importance of following company safety practices. The single-phase rotor test is highlighted as a simple yet effective method for assessing the condition of a rotor in a service center environment, where various voltage supplies are available. The video concludes by encouraging viewers to apply these techniques in their motor repair practices.