1. Application place
•High bay lights are suitable for the lighting of large and spacious areas such as factories, power plants, steel mills, workshops, mines, warehouses, stadiums, waiting rooms, airports, etc. They are generally used for global lighting with high suspension.
• In addition to various lighting lamps used in normal environments, there are explosion-proof lamps and anti-corrosion lamps used in special environments.
• According to the light source, there are mainly metal halide lamps, energy-saving lamps, electrodeless lamps, and other gas discharge lamps, fluorescent lamps, LED lamps
• LED high bay lights based on BlumiBay non-special requirements
Second, the composition of lamps and lanterns
Drive: Provide the power required by the lamp, and the output level can be controlled by the controller
Controller: Pass signals to enable remote control (Zigbee)
Led: produces light of different qualities (CCT, CRI)
PCB: LED fixed carrier, but also a carrier for electrical and thermal connection
Optical parts: form different light distributions
Shell: The structure of all parts is fixed and used as a radiator
Drive box: fixed drive is also a mechanical connection for hoisting
Three, lighting design
Clarify product positioning and usage requirements:
Quality (>110lm/W, CRI>80……);
IP65/IP20 is suitable for a variety of use environments;
3-5 years service life;
Remote viewing and control
…
Meet basic needs;
IP20 indoor use;
1-year service life;
Lower cost
…
3.1 Optical requirements and device selection
• LED selection
First choose high-power LEDs, based on cost considerations, generally choosing medium-power LEDs can also meet the demand
Calculate and select the matching LED for the entire lamp system, and select the corresponding CCT, CRI, etc. according to customer needs
•PCB design
LED layout, designed according to relevant design specifications, and coordinated with the housing, lens, and other related connectors
•Optical parts
Choose the corresponding material according to different application requirements
3.2 Lamp structure
•According to the structure, it is mainly divided into two categories: IP protection requirements (≥IP65) and no IP protection requirements (IP20).
The cost is lower.
•According to different types of light sources, it can be divided into point light sources (replacement of metal halide bulbs) and line light sources (replacement of fluorescent tubes).
The lamp uses a die-cast aluminum shell and electrical box, and the surface of the die-casting parts is electrostatically sprayed.
The light-emitting surface is protected by 5mm thick tempered glass. The lamp housing can pass IK08 or more, and the glass can also reach IK07 or more.
The electrical box adopts a split design, which can effectively prevent the heat of the light board and the driver from interacting with each other. The built-in PMMA high light transmission lens can achieve different light distribution angles through different designs.
3.3 Lamp heat dissipation
Main effects of heat dissipation:
•Lamp weight (size, material…)
• Lamp efficiency
•Lamp life
PCB is the first path for LED heat conduction. If the thermal resistance of the PCB is too large, the heat generated by the LED will accumulate.
There will be a large temperature difference between the LED and the radiator. In order to control the LED at a certain temperature, it is bound to improve the heat dissipation performance of the radiator and increase the cost of the radiator.
The fewer PCB layers of the same type, the better, the thinner the thickness of the layer, the better (except for the copper layer), the larger the layer area, the better, the larger the thermal conductivity of the material, the better, and the smaller the thermal resistance.
Main PCB types: CEM1, CEM3, Super CEM3, FR4 vias, MC-PCB, thermal performance, and price gradually increase from left to right.
For the requirements of IP65 and above, die castings are generally selected as the shell and radiator, which is conducive to structural design and can provide high-efficiency heat dissipation performance.
For lamps below IP65, considering the price advantage, the outer shell can be made of sheet metal, plastic, etc., and the internal heat sink can be formed by extrusion, sheet metal, and other processes.
Since the heat dissipation efficiency of the radiator is very low inside, in order to improve the heat dissipation performance, on the basis of not affecting the appearance, a suitable airflow path is designed in the opening of the housing to improve the heat efficiency.
The operating temperature of the Driver generally does not exceed 60 degrees. For high-power LED high bay lights, the driver’s heat loss is higher.
General precautions for the heat dissipation of the Driver are 1. Keep a certain distance between the LED and the Driver to reduce the mutual influence of heat sources
2. Place the LED and Driver in a separate cavity. Ensure that the Driver’s tc surface is in contact with the external housing.
3.4 Integration and interface design
LED PCBA fixing and connection:
The contact between PCBA and the housing (heat sink) directly affects the heat dissipation of the LED, and the warpage of the PCBA has a greater impact on the heat dissipation.
PCBA fixed:
Generally, use M4 or M3 screws. On die-cast aluminum housings, pre-tapping is required.
The reason for not using self-tapping screws is that the aluminum chips will be scratched out by the screws, which will cause the aluminum chips to be stained on the PCBA.
However, self-tapping screws can only be used on the sheet metal shell. If the tightening torque is required, the holes of the sheet metal can be made into tapping holes (each hole is expensive 0.1-0.2RMB).
PCBA and Driver connection:
Terminal blocks can be used, which are easy to assemble and has high reliability, but the cost is more expensive.
More often, in order to save costs, it is directly completed by soldering, and at the same time, it can save the area of the PCB.
Fixing of the LED control device
The current LED control device Driver is generally fixed with screws, and safety regulations require at least two screws to fix the driver. However, in actual application,
In order to ensure sufficient contact between the drive and the electrical box/power supply base plate (safe grounding/heat dissipation requirements), more screws will be used.
Sometimes, in order to ensure that the drive has better access to the electrical box or housing, it is necessary to change the structure of the electrical appliance bottom plate or design an auxiliary bracket.
Sealed structure design
The glass and sealing rubber ring are sealed by screws +. Assembly and disassembly are relatively simple, but there are more parts.
Client power access design:
There are two conventional power access methods:
① Reserve a power cord to connect to the customer’s power supply (connected to the customer’s junction box);
②Reserving wiring terminals, the client’s power cord is directly connected to the lamp.
At present, the first method is mostly used, which can avoid the customer’s disassembly and assembly of the lamp part,
and ensure the reliability of the product, especially if there is an IP requirement, and avoid the IP failure caused by the customer’s disassembly and assembly.
Installation design:
There are generally 3 common installation methods, hoisting, pole-mounting, and bracket-mounting:
3.5 Safety design
Corresponding to the place where the interface is installed, anti-loose parts must be added to ensure the safety of the product after installation.
4. Design verification
test item:
• Power test
• Thermal test (LED, drive)
•Light distribution test
• Suspension test (4*weight, 1 hour)
• Vibration test
•Impact test
• Wind test (outdoor)
•IP test
•High temperature and low-temperature test