Electrical five anti as follows: 1, to prevent on-load points, co-isolation switch. (Circuit breakers, load switches, contactors closing state can not operate disconnectors.) 2, to prevent misclassification, error breaker, load switch, contactor. (Only the operating instructions in order to correspond with the operation of the device is operated device operation) 3, to prevent the grounding switch in closing circuit breakers, load switch in the closed position. (Only when the grounding switch is in the open state of high and low voltage power distribution systems, in order to co-isolation switch or trolley to get into position to work high and low voltage power distribution, in order to operate the circuit breaker, sub-charge switch is closed) 4, to prevent misuse when live together grounding switch. (Only the circuit-breaker status, in order to operate the isolation switch or handcart to retreat to test high and low voltage power distribution equipment manufacturers position from the operating position to close the grounding switch) 5, to prevent mistakenly charged compartment. (Only the compartment when not energized type of high and low voltage power distribution equipment, in order to open the door to enter the compartment) Notes frequency control cabinet maintenance and repair of the 21st century, the domestic inverter technology has been rapid development, has been widely used in national various sectors of the economy, promoting energy saving, which greatly improves the level of China's industrial electrical transmission. But with the promotion and application of the drive, we need to pay attention to and dissatisfied outstanding issues slowly surfaced. Here's to study the frequency control cabinet maintenance and repair problems. High and low voltage distribution systems _ Xi Connaught Electrical and Mechanical (certified) _ Xinyang City, Henan high and low voltage distribution provided by the Electrical and Mechanical Equipment Co., Ltd. Connaught learning. Henan Xi Connaught Electrical Equipment Co. (www.hnxinuo.com) is Zhengzhou, electronics, electrical products processing leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. In practice Connaught Electrical and Mechanical leadership with the staff warmly welcome all inquiries negotiations to create learning Connaught Electrical and Mechanical better future.