Drive repair entry - good or bad light emitting diode emitting diode test test good or bad, positive and negative resistance can be tested in accordance with test method ordinary silicon diodes. Refers to the bell multimeter dial in R * 100 or R * 1K file converter, with a black pen then the positive vector converter light-emitting diode, the red pen then negative, positive resistance should be measured at 20 = 40K; light-emitting diodes connected with black pen negative inverter principle, the red pen then the positive drive prices, measured reverse resistance should be greater than 500K or more. Diode-speed dial with a digital multimeter, black pen then the positive light-emitting diodes, the red pen then negative, resistance is infinite. Black pen then the negative light-emitting diodes, the red pen then positive, there will be micro-light emitting diodes indicate normal. Soft-start maintenance; abb soft-start maintenance; ab soft-start maintenance; 6RA23 maintenance; 6RA22 maintenance; PLC maintenance; Siemens soft-start maintenance; 6RA22 repair; elevator drive repair; Omron PLC repair; motor drive repair ; omron PLC maintenance; Panasonic PLC maintenance; DC governor maintenance; Hitachi PLC maintenance; 6RA24 maintenance; 6RA23 repair; 6RA24 repair; on the drive _ Shenyang China on China (certified) _ Drive by the people on the Shenyang Electric Company. Shenyang on China Electric Co. (www.zsmsy.com) Liaoning Shenyang, the other leaders, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Shenyang people in leadership with the staff warmly welcome all inquiries negotiations to create Shenyang on a better future for the people.