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To ensure the safe, reliable, and economical operation of motors and to prevent abnormalities such as damage to important motors, the relevant requirements for motor operation management are specified as follows. I. Inspection items for starting and stopping the motor: 1. The starting and stopping operations of the motor must be monitored by someone. The operating duty personnel shall conduct pre-startup or post-shutdown inspections on the motors that are to be started or shut down, in accordance with their job responsibilities. 2. The external inspection items before starting the motor are: (1) There should be no debris on or around the motor (including its rotating parts), and no one should be working in that area; the grounding wires of the motor and its starting device must be in good condition, and the protective covers over the rotating parts must be intact. (2) The machinery driven by the motor is ready and can be started. (3) The oil level in the bearings and starting devices should be normal. For those requiring intensive lubrication, the oil system should be put into operation; for bearings cooled by water, the cooling water supply should be activated. (4) The starting device should be in the starting position. For DC motors, it is required that the surface of the commutator be in good condition and that the brush contact be tight. (5) For motors with enclosed air cooling (such as electric feedwater pump motors), the air cooler should be activated before starting. (6) The screws of various parts of the motor, the enclosure grounding wire, cable junction boxes, etc., should be in good condition. (7) The standby motor should be checked regularly to ensure it can start at any time. (8) If possible, before the first start-up after maintenance, try to rotate the rotor together with the maintenance personnel to confirm that there is no friction between the rotor and the stator, and that the machinery driven by it is also free of faults. Safety measures to prevent accidental closing should be in place before rotating the rotor. (9) Is there any reversal caused by mechanical factors? If so, measures should be taken to stop this reversal, and the motor must not be started while it is reversing. (10) The indications or displays of the temperature measurement devices in various sections shall be correct. 3. When starting the motor, the operator should monitor the entire starting process. After the start is complete, it is necessary to check whether the motor current exceeds the rated value. 4. Under normal circumstances, try to avoid starting motors under load. For motor equipment along coal transportation routes, each level of equipment should be started in the opposite direction to the flow of coal, in order to prevent coal from escaping or getting stuck, as well as to avoid damage to the motor equipment resulting from starting the equipment under load ； For fans and pumps that are started under normal conditions, it is also necessary to first confirm that elements such as the fan dampers or outlet electric doors are in a closed state, to ensure that the motor starts under no-load or light-load conditions. 5. In the event of an accident, a delay in the equipment’s startup time can severely affect the load; it may even lead to an MFT or compromise the safe and stable operation of the unit. If the motor does not have protections such as overcurrent or differential protection, it is possible to start the equipment under load urgently, depending on the circumstances on site, in order to ensure the stability of the unit’s system. 6. Regulations on the number of motor startups: Under normal conditions, a squirrel-cage motor is allowed to be started twice while cold, with an interval of no less than 5 minutes between each startup ； Start it once while it is hot. Only once is an additional start allowed when dealing with an accident, provided that no abnormalities are detected in the equipment’s appearance and parameters. (Hot state: The natural stop state after the motor is operating at its rated load.) Cold state: The condition of the motor 4 hours after it has stopped operating under its rated load; at this time, the temperatures of all parts of the motor are close to the ambient temperature. ) II. Inspection tasks and related work during electric operation 1. When the motor is in operation, the duty personnel should: (1) Monitor and record the motor’s operating current to ensure it does not exceed the allowable values for that equipment; also monitor the temperature of various parts of the motor (including the core and coils) to confirm that there are no signs of overheating such as smoke or a burnt smell. (2) Pay attention to whether there are any abnormal noises from the motor; if an abnormality is detected and it cannot be determined, contact the maintenance personnel to assist in making a judgment. (3) Check whether the lubrication and temperature of the bearing are normal. For bearings with oil ring lubrication, pay attention to whether the oil ring rotates smoothly, and the oil level in the bearing housing should be normal (be careful of false oil levels). For bearings that require strong lubrication, it is necessary to check that the oil system and cooling water system are operating properly. (4) For DC motors and wound-rotor motors, attention should be paid to whether there is arcing at the slip rings or commutators, and whether the brushes are jumping. (5) Pay attention to the temperature of the motor and its surroundings ； Keep the area around the motor clean (there should be no coal ash, moisture, oil stains, metal wires, cotton fibers, etc., to avoid being drawn in) ； Clean the motor regularly. (6) For motors with air-cooling, it is necessary to check for any leaks of water, air, or oil. The water pressure and flow rate of the air cooler should be normal, with no signs of leakage or condensation. (7) Record the relevant meters of the motors in accordance with departmental regulations. For 6KV auxiliary equipment, it is necessary to carefully record the start and stop times and reasons as required by the reliability management regulations, as well as any abnormal phenomena observed. (8) The area around the motor should always be kept dry and clean to prevent water, steam, and oil from entering. Personnel in sanitation duties must be firmly prevented from using water to wash the ground directly near the motor. (9) Under any operating conditions, the maximum monitoring temperature and temperature rise of the motor windings and core shall not exceed the values specified by the manufacturer. If no specifications from the manufacturer are provided, monitoring shall be carried out in accordance with the electrical operation procedures. (10) The bearing vibration of the motor during operation shall not exceed the following values: Rated speed (rev/min): 3000, 1500, 1000, 750 and below. Vibration value (double amplitude, in mm): 0.05, 0.085, 0.10, 0.12. Thrust movement (in mm): Rolling bearings – 2–4; Sliding bearings – 0.05. III. Regular maintenance of motor equipment 1. Requirements for the motor’s insulation resistance: (1) Before powering on the motor again after maintenance (including mechanical repairs), or after it has become damp, its insulation resistance must be measured. This value should be recorded in the insulation log with a signature for future reference; the motor may only be powered on if the resistance is within acceptable limits ； Power supply shall not be initiated if it does not meet the requirements; under special circumstances, power supply may only be carried out with the approval of the chief engineer. (2) In cases where the power outage lasts for seven days or more, the insulation resistance must be measured before power is restored. If the motor operates in a poor environment and the power outage lasts for five days, the insulation resistance must also be measured before power is restored. For motors in dry autumn and winter seasons as well as those in favorable working environments, the interval between insulation resistance measurements can be extended to 15 days. (3) For the bearing insulation of large electric motors after major repairs, operators must require maintenance personnel to conduct measurements using a 1000-volt megohmmeter, and the insulation resistance must meet the specified requirements. (4) For the insulation resistance of 6KV high-voltage service motors, measured under the same environmental and temperature conditions, if the value obtained in this measurement is less than 1/3 to 1/5 of the previous measurement value, the cause must be identified, and the absorption ratio R60″/R15″ must be measured; this value should be greater than 1.3. (5) The insulation of cold standby motors should be measured regularly (every half month). When measuring the insulation resistance of a motor that is in standby mode, it is necessary to inform the shift supervisor, the chief engineer, and the persons in charge of the relevant departments. The measurement can only be carried out after obtaining their approval and after the persons in charge of the relevant departments have taken the necessary measures. After the insulation resistance measurement shows satisfactory results, the motor must be restored to its original state, and the results must be reported to the shift supervisor and the persons in charge of the relevant departments. (6) Each specialty should increase the frequency of insulation measurements as appropriate based on the on-site environmental conditions, especially during the rainy season or seasons with high humidity that lead to dew formation. (7) The insulation resistance of the motor stator windings should generally be no less than 1 megohm per kilovolt of operating voltage. For those with a working voltage of 1 KV or less, it should not be less than 0.5 megohms. The insulation resistance of the wound rotor coils should not be less than 0.5 megohms. The equipment should show no signs of moisture; otherwise, it must be dried until its insulation meets the required standards before it can be put into operation. It is prohibited to put motors with inadequate insulation into operation; in special cases, approval from the chief engineer is required. (8) If a moisture-proof heater is installed inside the motor casing as needed, it should be turned off during operation. 2. The motors should be regularly switched over or tested in accordance with regulations to ensure the reliability of the standby motors. During the rainy season or when the humidity is high, the insulation of the standby motor should be checked to ensure it is in good condition before starting it; otherwise, maintenance personnel should be notified to address the issue promptly so that the motor can return to its normal standby state as soon as possible. 3. The motor should be cleaned regularly and its bearings should have oil replenished. Due to environmental factors at the production site, there are certain electric motors, especially those located along the coal transportation routes, in the ash and slag handling systems, and in areas affected by these systems. Dust can affect the quality of the bearing oil in these motors as well as their cooling systems, leading to malfunctions. Operators should inform maintenance staff to carry out regular cleaning based on the current conditions. IV. Judgment and handling of common abnormalities during motor operation. Refer to the sections in the electrical operation procedures regarding abnormal phenomena of motors and their causes.