When selecting the model, first confirm that the rated voltage and rated current of the product are not lower than the actual operating parameters of the circuit, then verify the breaking capacity according to the short-circuit current of the loop, and adjust the selection margin in combination with the temperature, humidity and dustproof level of the use environment. During installation, ensure that the box is horizontal and vertical with a vertical deviation of no more than 3mm. The N-line and PE-line in the box must be equipped with separate busbars. It is strictly forbidden to twist the wires directly, and all metal shells must be reliably grounded. For daily maintenance, focus on checking whether the contacts are overheated and oxidized, and whether the protection setting value is deviated. Regularly clean the dust on the product surface to avoid the leakage hazard caused by insulation degradation.

Distribution Board (DB)‌：Verify power parameter match, tighten terminals de-energized, test circuits step-by-step on power-up ‌VFD & Soft Starter‌：Preload motor nameplate data, separate AC/DC wiring, no-load test before load connection ‌Contactor‌：Confirm coil voltage, 30% overcurrent margin for main contacts, check no mechanical jam pre-power-on ‌Motion Control‌：Load config file post-wiring, single-axis jog test first, then run full linkage sequence ‌Relay‌：Isolate coil & contact pins, match load rating, use interposing relay for PLC port protection ‌Motor Protection‌：Set threshold at motor FLC, simulate fault to confirm protection trip action ‌Signal Control‌：Shielded & grounded cable for analog, match signal type to PLC port, twisted pair for digital anti-interference ‌Industrial Power Supply‌：20% power reserve, confirm polarity, UPS backup for critical loops ‌Sensor‌：Mount away from EMI zones, validate signal sync with measured physical value ‌General Rule‌：All work performed de-energized; scheduled maintenance drastically extends equipment lifespan

Step 1: set the ambient temperature, humidity, corrosion, indoor/outdoor weather-resistant type (UV-proof, waterproof); High temperature heat-resistant 105 ℃ grade; Chemical plants choose anti-corrosion coating.

Step 2: Calculate electrical current, voltage and short-circuit dynamic thermal stability. Select wire diameter according to load current look-up table → Select terminal/connector aperture according to wire diameter → Select insulator grade according to voltage.

Step 3: Check the bending strength of insulators for mechanical self-weight, tensile force, vibration and wind-resistant large-span bus. Vertical laying cables need to be armored or equipped with clamps.

Step1: distinguish the material, shape and batch size of the object to be processed by the task, and select manual/general tools in a small amount. Repeat the selection of electric/pneumatic special fixtures in large quantities.

Step 2: The parameters marked with torque/rotating speed/clamping range/shear limit/protection level must have a margin (e.g. 20% safety margin is reserved for shear force, and power of electric tools is selected from large to small).

Step 3: Select short handle/elbow tools in narrow space with human-machine operator's physical strength, working space height and power supply and gas supply conditions; Anti-falling rope must be provided for high-altitude operation, and heavy wired tools are prohibited.

Step 1: Set goals for energy saving/safety/comfort/compliance Take commercial buildings as an example: energy saving depends on energy storage + intelligent lighting; Safety depends on security + alarm linkage.

Step 2: Draw topology strong current topology + weak current mesh structure. First draw distribution box to each circuit (electrical and electrical materials); Then draw weak current box to each AP/camera (network); Finally, lay out the sensor position (measurement + alarm).

Step 3: Select whether the protocol communication protocol is unified as far as possible to Zigbee 3.0 or Bluetooth Mesh (wireless) and RS485/Modbus (wired); Avoid fragmentation of App of different brands.

Step 4: Calculate redundancy and reserve standby switch for expansion allowance distribution box; NVR reserved double plate position; PoE switch power reservation ≥ 30%.