Single-phase motor centrifugal switch's cut-off  speed measurement method

JIN Jian-jun，ZHANG Yun
（Wenling Institute of Supervision & Testing on Product Quality， Wenling 317500，China）

Abstract： In order to solve the problems of the single-phase motor centrifugal switch's cut-off speed measurement method，without the specialized test equipment，the widely used feedback control motor test system was applied in data acquisition. After the analysis of torque - speed and current - speed characteristic curve，the relationship between torque and centrifugal switch cut-off point，current and centrifugal switch  cut-off point was established.A method was presented to identify the centrifugal switch cut-off point.The situation of centrifugal switch cut-off were evaluated on several sample motors which has typical characteristic curves，the conclusions of compliance and usability were given.The experimental results show that the method has directive to either inspecting departments which use it to measure centrifugal switch cut-off speed，or motor manufacturing enterprises which use it to make failure judgment and model selection to centrifugal switch.
Key words： entrifugal switch；cut-off speed；feedback control；motor test system；secondary off