Here is the answer to how to determine the wiring method of wires and cables in electrical control cabinet:
1. Classification based on line function
First, wires and cables should be classified according to the function of the line. Power lines are mainly used to transmit high-power electrical energy, such as connecting motors, heaters and other equipment, and usually have large currents. For power lines, in order to avoid electromagnetic interference between each other and other lines, separate wiring areas are generally used. For example, the power lines can be concentrated on one side or the bottom of the control cabinet, using thick-diameter cables and ensuring sufficient spacing. Signal lines are different. They transmit control signals, which are mostly weak current signals and are very sensitive to electromagnetic interference. Signal lines should be wired separately from power lines. Troughs or pipes can be used, such as concentrating signal lines on the upper part or the other side of the control cabinet to ensure that there is enough distance between the two, generally not less than 300mm, to prevent the magnetic field of the power line from interfering with the signal line.
2. Consider electromagnetic compatibility
Electromagnetic compatibility is an important factor in determining the wiring method. In the electrical control cabinet, different electrical components will generate electromagnetic fields when working. To reduce electromagnetic interference, special attention should be paid to the wiring near components that are prone to electromagnetic interference (such as inverters, contactors, etc.). For strong power lines, twisted pair or shielded cables can be used to reduce the impact of electromagnetic radiation generated by themselves on the outside world. For weak signal lines, such as analog input and output lines, communication lines, etc., shielded cables must be used, and the shielding layer must be grounded at one end. In addition, layered wiring can also be used, such as arranging the power line at the bottom layer, the middle layer for the control line, and the top layer for the signal line, using the principle of electromagnetic shielding to reduce electromagnetic interference between different lines.
3. Combining the structure and spatial layout of the control cabinet
The structure and spatial layout of the control cabinet will also affect the wiring method. If the internal space of the control cabinet is relatively compact, the wiring needs to be planned more carefully. For example, wire troughs, bridges, etc. can be used to regularize the direction of the line. For larger control cabinets, wiring can be carried out according to different functional areas, such as setting up special power areas, control areas, and signal areas. At the same time, the convenience of wiring should be taken into account to avoid too many line crossings and make the line direction clear. When laying out, a certain margin should be reserved for wires and cables so that they can be easily operated during maintenance, overhaul or component replacement. The reserved length is generally 10% - 20% of the distance between the terminal and the component.
4. Follow safety and maintenance requirements
Safety and maintenance are aspects that cannot be ignored during wiring. From a safety perspective, all wires and cables should be kept away from high temperature, moisture and sharp objects. For lines that may produce arcs, such as the inlet and outlet lines of circuit breakers, sufficient insulation distance should be ensured. In terms of maintenance, wiring should be convenient for future inspection, maintenance and troubleshooting. This requires clear and accurate line identification, and each terminal should have a clear line number identification. For lines that need to be frequently plugged in and out, easy-to-plug and unplug connection methods should be used, such as plug-in terminals. At the same time, for the wiring of multiple cables, it is necessary to consider how to facilitate the search and distinction of different lines, such as using cables of different colors or sticking labels on the cables.
