When renovating your home, installing electrical wiring is essential. The materials and installation of wiring are crucial to future electrical safety. To ensure safe use and a smooth installation, let's take a look at some basic wiring tips!
How should home wiring be installed?
It's recommended to use rigid wiring, also known as BV plastic copper wire. BVV or ZRBV wire can be used if available. The civil building electrical engineering acceptance standards require that rigid single-strand plastic copper wire, also known as BV wire, be used for indoor residential wiring. Rigid wiring has thicker insulation than flexible wiring, and its mechanical strength and aging resistance are significantly better than those of flexible wiring, resulting in higher safety performance. The biggest disadvantage of rigid wiring is that it's more difficult to install, resulting in higher labor costs. Furthermore, it's not suitable for flexible connections.
Due to its low mechanical strength, flexible wire is not suitable for concealed wiring in conduit, where it can easily break. It's also not recommended for home decoration. It also has poor aging resistance, making it unsafe for long-term use. Soft furnishings are best suited for applications requiring flexible connections, such as when making a power strip or temporarily connecting a light bulb. You can see this with purchased power strips. Flexible wire is also particularly convenient to install because its flexible conductors are easier to route and connect, and labor costs are lower than with rigid wiring.
Home wiring diameter selection:
2.5 mm² for lighting;
2.5 mm² for regular outlets;
4 mm² for cabinet air conditioners;
4 mm² for kitchens and bathrooms.
Typically, the live wire is red, the neutral wire is blue, and the ground wire is yellow-green. When wiring, always follow the principles of "live wire at the switch, neutral at the connector" and "neutral wire on the left, live wire on the right, ground wire on the top."
What are some common wiring guidelines for home renovations?
1. When designing wiring, follow the principle of routing high-voltage cables upwards and low-voltage cables downwards, maintaining horizontal and vertical alignment to avoid crossovers and ensure aesthetics and practicality.
2. Grooving depth should be consistent, generally equal to the PVC pipe diameter + 10mm.
3. When routing power cables, the cross-sectional area of the wire used should meet the maximum output power of the equipment. Generally, 1.5 square meters is used for lighting, 2.5 square meters for sockets, 4 square meters for air conditioners, and 10 square meters for service lines.
4. Concealed wiring must be installed with flame-retardant PVC pipe. SG20 pipe should be used for sockets, and SG16 pipe for lighting. If the pipe length exceeds 15 meters or has two right-angle bends, a cable tie box should be added. A cable tie box should be installed at the ceiling lighting fixture.
5. PVC pipes should be secured with pipe clamps. Use matching PVC pipe joints, secure with PVC glue, and bend with springs. Secure concealed boxes, cable ties, and PVC pipes with grommets.
6. After the PVC pipe is installed, all wires should be routed uniformly. Wires for the same circuit should be routed through the same pipe, but the total number of wires in a pipe should not exceed eight. The total cross-sectional area of the wires (including the insulation) should not exceed 40% of the pipe's cross-sectional area.
7. Power cords and communication cables must not be routed through the same pipe.
8. The horizontal spacing between power cords and sockets and TV cables and sockets should be at least 500mm.
9. The parallel distance between electrical wires and heating, hot water, and gas pipes should be at least 300mm, and the cross-sectional distance should be at least 100mm. 10. Connectors for wiring entering the conduit should be located in the junction box, with a 150mm margin left for the wire ends. The joints should be securely overlapped, and the insulation tape should be wrapped evenly and tightly.
11. When installing a power socket, the neutral wire (N) should be connected to the left side facing the socket, the phase wire (L) to the right side, and the protective earth (PE) wire to the center and top. The protective earth wire should be a 2.5mm square, two-color flexible wire.
12. When a chandelier weighs 3kg or more, first install the post-embedded hardware on the ceiling, then secure the fixture to the post-embedded hardware. Installation on wooden wedges or wooden bricks is strictly prohibited.
13. When connecting switches and screw-type lighting fixtures, the phase wire should be connected to the switch first. The phase wire from the switch should be connected to the terminal in the center of the lamp, and the neutral wire should be connected to the threaded end.
14. The resistance between wires and between wires and ground must be greater than 0.5MΩ.
15. The bottom edge of a power socket should be 300mm from the ground, and the bottom edge of a flat switch panel should be 1300mm from the ground. The height of a wall-mounted air conditioner socket is 1900mm. The height of a detachable outlet is 2100mm. The height of a kitchen socket is 950mm. The height of a wall-mounted disinfection cabinet is 1900mm. The height of a washing machine is 1000mm. The height of a television is 650mm.
16. The socket panels of power, telephone, and televisions in the same room should be at the same level, with a height difference of less than 5mm.
17. Each household should have a power distribution box. The distribution box should be equipped with a 30mA leakage protector. After the circuit breaker is switched, the circuit breaker controls lighting, air conditioning, outlets, and other devices. The operating current of the switch should match the maximum operating current of the terminal appliance. Generally, lighting is 10A, outlets are 16A, cabinet air conditioners are 20A, and household power lines are 40-60A.
The above is an introduction to household wiring installation and common wiring knowledge. I believe you have already learned some basics. Whether you hire a contractor or install the wiring yourself, always pay attention to safety and choose wiring from reputable manufacturers.
