When we walk on the road at night, we will find that there are many colorful lights on both sides of the road or near some public places. The purpose of these lights is, on one hand, for illumination, and on the other hand, a very important aspect is to beautify the city, which is what we call landscape lighting, allowing the city to have beautiful scenery at night. To achieve this effect, certain precautions must be taken during the landscape lighting project. Before introducing the precautions, I would like to first introduce the construction process of the landscape lighting project, which is quite complex. Interested friends can take a look and learn about it.

Construction process of landscape lighting project:

1. Trench excavation

a. Excavate a trench with a width of 400mm and a depth greater than 450mm.

b. When excavating, use a ruler to draw control lines, determine the direction of the trench, and avoid damaging the landscape and underground facilities.

c. When backfilling, compact the soil, and restore the trench through the hard surface with concrete mortar.

2. Cable laying

a. The cable model, voltage, and specifications should meet the design requirements. Before laying, perform insulation testing on the cable, with insulation resistance greater than 0.5MΩ.

b. Before laying, calculate the length of each cable according to the design and actual path, arrange each cable reasonably, and reduce cable joints.

c. When laying cables in live areas, reliable safety measures should be in place.

d. There should be spare length near the terminal and joint of the power cable.

e. The minimum bending radius of the cable should be greater than 20D of the cable outer diameter.

f. When laying cables, the cable should be drawn from the top of the reel, and the cable should not be dragged or rubbed against the support or ground. The cable should not be crushed, twisted, or have any unresolved mechanical damage such as broken sheaths.

g. For parallel laid power cables, the positions of the cable joints should be staggered.

h. Cables should be arranged neatly during laying, should not cross, should be fixed, and signs should be installed in a timely manner.

i. The cables for this project are conduit cables, with a distance of no less than 40CM from the ground surface. At the intersection of buildings, they can be buried shallowly but should take protective measures. When crossing hard surfaces, steel pipe protection should be added.

3. Wire threading through pipes

a. The diameter of the pipe should be determined based on the number of wires being threaded. The insulation resistance measurement of the wires should not be less than 0.5MΩ. Wires from different systems and circuits are strictly prohibited from being threaded in the same protective pipe, and there should be no joints or twists in the protective pipe.

b. Equipment grounding wires and dedicated grounding wires must use multi-strand copper core wires.

c. When wires are threaded into steel pipes, protective sleeves should be installed at the pipe openings to protect the wires, and the vertical pipe openings of the boxes should be sealed after the wires are threaded in.

4. Pipeline laying

a. The plastic pipes and fittings used to protect the wires must be made of flame-retardant materials. The outer wall of the plastic pipes should have flame-retardant markings and manufacturer labels spaced no less than 1 meter apart.

b. When connecting pipes, the outer sleeve length should be 1.2-3 times the pipe diameter, and the joint between the pipes should be located at the center of the sleeve.

c. When laying plastic pipes on brick walls, a cement mortar with a strength grade of no less than M10 should be used for surface protection, with a protective layer thickness of no less than 12mm.

5. Steel pipe laying

a. In damp places and for wires buried directly underground, thick-walled steel pipes should be used.

b. Steel pipes should not have flattening or cracks, and there should be no iron filings or burrs inside the pipes. The cut ends should be smooth.

c. When using sleeve connections, the sleeve length should be 1.5-3 times the outer diameter of the pipe, and the joint between the pipes should be located at the center of the sleeve. When using welded connections, the welds should be firm and tight; when using set screws, the screws should be tightened, and in vibrating locations, there should be measures to prevent loosening.

d. Galvanized steel pipes should use threaded connections or sleeve set screw connections, and welding connections should not be used.

6. Fixture installation

a. Assemble the qualified high-quality streetlight fixtures on the ground, ensuring that all electrical components inside the fixtures are securely fastened. After assembly, power on to test the lights.

b. Transport the intact fixtures to the site, taking care to prevent surface scratches or impacts during transportation.

c. Streetlight installation should be vertical, using a water level to adjust its verticality.

d. The metal shell or base of all fixtures must be connected to the PE wire and reliably grounded.

7. Control cabinet installation

a. The control box should be installed securely, with a vertical deviation not exceeding 3mm; the bottom edge height from the ground should meet design requirements.

b. The control box position should be close to the cable trench inspection opening, leaving space for maintenance work and paying attention to waterproofing.

c. The incoming and outgoing lines of the control box should be neat, and the positions and angles of the outgoing lines should be reasonable.

d. Inside the control box, separate busbars for neutral and protective ground (PE) should be set up and reliably grounded.

e. Each circuit switch inside the control box should be clearly labeled.

8. Production and installation of cable terminal heads and cable intermediate heads

a. The production of cable heads should be carried out by trained personnel familiar with the process, strictly adhering to the production specifications.

b. Make cable terminal joints, starting from stripping the cable and continuously operating until completion, to shorten the insulation exposure time, and ensure that the core wire and retained insulation are not damaged during stripping.

c. In addition to sealing the insulation with self-adhesive tape and waterproof tape, epoxy resin should also be applied to enhance sealing and moisture-proof treatment.

d. The cables on both sides of the cable joint should be connected well without interruption, and the cross-section at the joint should not be less than that of the grounding electrode.

e. The cable should be reliably grounded and soldered to the ground.

9. Grounding Electrode (Grounding Protection) Construction

a. Grounding protection should be installed strictly according to the requirements of electrical construction specifications, with the working neutral line and protective neutral line kept strictly separate and not mixed. All PE lines in distribution boxes should be vertically grounded. If testing exceeds standard requirements, rework must be requested until standards are met.

b. Grounding electrodes and grounding flat steel should be made of hot-dip galvanized steel, and the specified burial depth for grounding devices should not be less than 0.6M, with the grounding wire led to the ground surface outside at a depth of 0.6M.

c. Grounding electrodes should use ∠50×50×5×2500 galvanized angle steel, spaced 5M apart, and the grounding bus should use -40×4 galvanized flat steel, with the welding overlap length between grounding buses not less than 15CM, and anti-corrosion treatment should be done at the welding points between the grounding bus and grounding electrodes.

10. Debugging

a. Testing process: Low voltage switch box primary and secondary circuit testing → overall debugging → operation.

b. The debugging content of the low voltage switch box includes testing of the main circuit circuit breaker and contactor, secondary circuit testing, etc.

Things to pay attention to during the construction of landscape lighting projects:

1. Throughout the landscape lighting design process, designers should consider the environment of the landscape lighting, the surrounding environment and geographical location, combine the characteristics of their own city, highlight the structure of their own city, and avoid blindly imitating other cities to create a unique city lighting.

Landscape lighting varies in different regions, and the design process should integrate with the surrounding environment, outlining the city's appearance and reflecting the general shape, scale, and characteristics of the city.

2. After the overall design, the issue of landscape lighting construction arises. Lighting requires the use of lighting fixtures, and in material selection, energy-saving and long-lasting fixtures should be used to avoid excessive waste, as environmental protection is also very important.

3. During landscape lighting construction, efforts should be made to avoid causing noise and disturbing the daily routines of nearby residents. At the same time, light pollution should be avoided.

4. Strengthen management, and promptly repair any damaged areas. Standardize management, use scientific methods for management, and make better landscape lighting with limited resources.

The above is an introduction to the construction process and precautions for landscape lighting projects. If any friends are engaged in related work, they can take a good look at the precautions for construction.