Electrical Safety

General Requirements

• Follow the procedures described in the document for installation, operation, and maintenance. Do not reconstruct or alter the equipment, add components, or change the installation sequence without permission.
• Obtain approval from the national or local electric utility company before connecting the equipment to the grid.
• Observe the power plant safety regulations, such as the operation and work ticket mechanisms.
• Install temporary fences or warning ropes and hang "No Entry" signs around the operation area to keep unauthorized personnel away from the area.
• Before installing or removing power cables, turn off the switches of the equipment and its upstream and downstream switches.
• Before performing operations on the equipment, check that all tools meet the requirements and record the tools. After the operations are complete, collect all of the tools to prevent them from being left inside the equipment.
• Before installing power cables, check that cable labels are correct and cable terminals are insulated.
• When installing the equipment, use a torque tool of a proper measurement range to tighten the screws. When using a wrench to tighten the screws, ensure that the wrench does not tilt and the torque error does not exceed 10% of the specified value.
• Ensure that bolts are tightened with a torque tool and marked in red and blue after double-check. Installation personnel mark tightened bolts in blue. Quality inspection personnel confirm that the bolts are tightened and then mark them in red. (The marks must cross the edges of the bolts.)

• If the equipment has multiple inputs, disconnect all the inputs before operating the equipment.
• Before maintaining a downstream electrical or power distribution device, turn off the output switch on the power supply equipment.
• During equipment maintenance, attach "Do not switch on" labels near the upstream and downstream switches or circuit breakers as well as warning signs to prevent accidental connection. The equipment can be powered on only after troubleshooting is complete.
• Check equipment connections periodically, ensuring that all screws are securely tightened.
• Only qualified professionals can replace a damaged cable.
• Do not scrawl, damage, or block any labels or nameplates on the equipment. Promptly replace labels that have worn out.
• Do not use solvents such as water, alcohol, or oil to clean electrical components inside or outside of the equipment.

Grounding

• Ensure that the grounding impedance of the equipment complies with local electrical standards.
• Ensure that the equipment is connected permanently to the protective ground. Before operating the equipment, check its electrical connection to ensure that it is reliably grounded.
• Do not work on the equipment in the absence of a properly installed ground conductor.
• Do not damage the ground conductor.
• For the equipment that uses a three-pin socket, ensure that the ground terminal in the socket is connected to the protective ground point.

Cabling Requirements

• When selecting, installing, and routing cables, follow local safety regulations and rules.

• When routing power cables, ensure that there is no coiling or twisting. Do not join or weld power cables. If necessary, use a longer cable.

• Ensure that all cables are properly connected and insulated, and meet specifications.

• Ensure that the slots and holes for routing cables are free from sharp edges, and that the positions where cables are routed through pipes or cable holes are equipped with cushion materials to prevent the cables from being damaged by sharp edges or burrs.

• Ensure that cables of the same type are bound together neatly and straight and that the cable sheath is intact. When routing cables of different types, ensure that they are away from each other without entanglement and overlapping.

• When cable connection is completed or paused for a short period of time, seal the cable holes with sealing putty immediately to prevent small animals or moisture from entering.
• Secure buried cables using cable supports and cable clips. Ensure that the cables in the backfill area are in close contact with the ground to prevent cable deformation or damage during backfilling.
• If the external conditions (such as the cable layout or ambient temperature) change, verify the cable usage in accordance with the IEC-60364-5-52 or local laws and regulations. For example, check that the current-carrying capacity meets requirements.
• When the temperature is low, violent impact or vibration may damage the plastic cable sheathing. To ensure safety, comply with the following requirements:
  • Cables can be laid or installed only when the temperature is higher than 0°C. Handle cables with caution, especially at a low temperature.
  • Cables stored at subzero temperatures must be stored at room temperature for at least 24 hours before they are laid out.

• Do not perform any improper operations, for example, dropping cables directly from a vehicle. Otherwise, the cable performance may deteriorate due to cable damage, which affects the current-carrying capacity and temperature rise.