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1. Electrical operators must maintain concentration; electrical circuits should always be assumed to be \"live\" until it is confirmed with a voltage tester that there is no electricity present. They must not touch such circuits with their hands, and they should not rely entirely on insulators, treating the circuits as live. 2. Before starting work, carefully check whether the tools you are using are safe and in good condition, and wear the necessary protective equipment to prevent accidents during work. 3. Necessary measures must be taken when repairing the wiring: warning signs stating “Work in progress – do not close the switch” should be placed on the switch handle or along the wiring to prevent others from restoring power to the system. 4. When using a voltage tester, pay attention to the voltage range for testing; it is prohibited to use it outside this range. The testers generally used by electricians should only be used for voltages below 500 volts. 5. All wires removed during work must be handled properly; the wire ends should be covered to prevent electric shock. 6. The wires and fuses used must have capacities that meet the specified standards; when selecting a switch, its capacity must be greater than the total capacity of the equipment it is meant to control. 7. After the work is completed, the temporary ground wire must be removed, and it should be checked to ensure that no tools or other items have been left on the pole. 8. After the inspection is completed, a thorough check must be carried out before powering on; it is necessary to ensure that everything meets the requirements and to coordinate with the relevant personnel before power can be supplied. 9. In case of a fire, the power supply must be cut off immediately, and the fire should be extinguished using carbon tetrachloride powder fire extinguishers or yellow sand; it is strictly prohibited to use water to extinguish the fire. 10. After the work is completed, all personnel must evacuate the work area, the warning signs must be removed, and all materials, tools, instruments, etc. must also be taken away; the original protective devices must be reinstalled immediately. 11. After the operation area has been cleared, the operator must conduct a personal inspection. If power is to be supplied for testing, it is essential to coordinate with the relevant personnel to avoid any accidents. Safety Operating Procedures for Power Transformation and Distribution I. Sequence of Operations for Turning Power On and Off 1. Sequence of operations for high-voltage isolators: (1) Sequence for turning power off: A. Disconnect the air switches and isolators of each low-voltage circuit. B. Turn off the low-voltage main switch. C. Disconnect the high-pressure oil switch. D. Disconnect the high-voltage isolating switch. (2) The sequence for powering on is the reverse of the sequence for powering off. II. Operation sequence for low-voltage switches: (1) Power-off operation sequence: A. Disconnect the air switches and isolating switches for each low-voltage circuit. B. Turn off the low-voltage main switch. (2) The power-on sequence is the reverse of the power-off sequence. III. Switching Operation Procedures 1. For users with high-voltage dual power supplies, any switching operation must be carried out after prior consultation with the power supply company and obtaining its approval; or following the instructions given by the power supply company, and at the specified time. Switching operations must not be performed arbitrarily on one’s own. 2. For switching operations, it is necessary to first connect the available circuit and then disconnect the original one, in order to avoid affecting the users. 3. Switching operations must not be carried out if a fault has occurred and its cause has not been identified. 4. The two circuit breakers should be locked immediately after each operation, and a warning sign should be placed on them. 5. Switching operations must be carried out by two persons (one to operate and one to supervise). Safety Inspection Procedures for Power Transformation and Distribution Equipment: 1. Upon receiving notification of a power outage, electricians shall pull down the relevant circuit breakers and remove the fuses. Lock the control handle, attach a warning sign, and place protective barriers around the equipment that has not yet been powered off. 2. After the high and low voltage supplies are turned off, it is necessary to conduct a voltage check before starting work. 3. When checking voltage at high levels, a voltage tester suitable for that high voltage level must be used. Insulated gloves that have passed the appropriate testing must be worn during this process. The tester should first be tested on live equipment; only after it has been confirmed to work properly can it be used for voltage checks. 4. Voltage testing should be carried out on both sides of the incoming and outgoing wires of the construction equipment. It is specified that voltage testing of outdoor power distribution equipment should be performed in dry weather. 5. After confirming that there is indeed no electricity, grounding the construction equipment and short-circuiting the three phases are basic safety measures to prevent sudden power restoration and protect the workers. 6. Ground wires should be installed at all possible points where power can be supplied to the construction equipment. In systems with dual-circuit power supply, when maintaining a busbar disconnect switch or isolating switch, load switch, it is necessary not only to open the disconnect switches on both busbars simultaneously, but also to attach ground wires to both ends of those disconnect switches. 7. When installing a ground wire, grounding should be carried out first and then the wire should be attached; the reverse order is followed when removing the ground wire. 8. The ground wire should be placed in a location where it is easily visible to the workers, and a “Work in Progress” warning sign should be attached to it. The work supervisor should regularly check to ensure that the ground wire remains in good condition. 9. It should be particularly emphasized that the switches for all aspects of the construction equipment must be completely turned off; the circuit breakers or isolators must be opened to ensure that there is at least one clear disconnection point in each section. It is prohibited to work on equipment that has only its oil switch disconnected. At the same time, attention must be paid to the possibility of power being fed back from the low-voltage side through the high-voltage side of the transformer. Therefore, the transformers related to the construction equipment must be disconnected from both high-voltage sides simultaneously. 10. When resuming work after an interruption, all safety measures should be checked again; work can only be restarted once everything is in order. When everyone has left the site, the interior should be locked, and someone should be stationed outside to keep watch.