In refrigerated display lighting retrofit projects, many people assume that replacing existing lights with higher-performance LED fixtures will automatically improve overall illumination.
However, in real applications, the final lighting performance is influenced by more than just the lighting product itself. Cabinet structure, shelf depth, installation position, and even the original refrigeration cabinet design can directly affect the performance of refrigerated display lighting.
During a recent lighting retrofit project for Freshippo, we encountered a typical example of this issue. The customer upgraded the original T8 fluorescent lamps to our higher-efficiency DC24V SLK refrigerated display lighting series with higher luminous efficacy and Ra90 LEDs. However, dark zones still appeared at the front of the shelves.
To identify the real cause of the problem, our team visited the store and re-evaluated the cabinet structure, installation position, and light distribution performance on-site
Why the Original T8 Cabinet Structure Affected the New LED Lighting
Before the retrofit, the refrigerated cabinet used traditional T8 fluorescent lamps. Since T8 tubes are relatively large in diameter, the cabinet manufacturer designed deeper shelf bends and front baffles to hide the lamps from customers’ direct view. In some cabinets, the shelf bending depth reached 28.8mm.
After the lighting upgrade, the customer replaced the original T8 lamps with Laidishine’s DC24V SLK series.
Compared with traditional T8 lighting, the SLK series features:
- Dense LED distribution
- Up to 130 lm/W luminous efficacy
- Ra90 LEDs for more natural and vivid product colors
- Waterproof design to prevent moisture ingress inside refrigerated cabinets
- DC24V low-voltage design for safer daily operation
- Constant current and constant voltage design for stable current output
- Compact triangular profile for easier hidden installation under shelves
However, several weeks after installation, the customer reported that the lighting mainly illuminated the middle and inner areas of the shelves, while the outer edge remained relatively dark.
Based on our previous experience with refrigerated display lighting design, we suspected that the original shelf-bending depth designed for T8 lamps caused the SLK installation to sit too deep within the shelf structure. As a result, part of the outward light distribution was blocked by the front baffle, preventing the light from fully projecting outward.
On-Site Investigation and Problem Verification
To verify this assumption, our technicians visited the store for an on-site inspection.
After careful observation, we found that the lighting issue mainly existed in the open multideck display cabinets. The front shelf baffle partially blocked the SLK lighting, limiting outward light distribution and causing the entire cabinet to appear darker than expected.
To test the effect, we removed the front baffle from one shelf section for comparison.
The improvement was immediately visible. After removing the front baffle, the shelf lighting became noticeably more uniform compared with the lower shelf section.
However, this was still not the optimal lighting condition. If the shelf bending angle and installation structure were redesigned specifically for compact LED refrigerated display lighting, the SLK series could achieve significantly better illumination performance.
At the current stage, removing the front baffle is a practical solution that helps improve lighting performance while minimizing modification costs. For further optimization, refrigeration cabinet manufacturers may need to redesign shelf bending structures specifically for modern LED lighting systems.
Why Installation Distance Matters in Refrigerated Display Lighting
This project clearly demonstrates that not every refrigerated display lighting solution is universally compatible with every cabinet structure.
To achieve the best lighting effect, proper installation conditions are essential.
When developing product specifications, our engineering team tests the optimal installation distance for each lighting series. For example, during SRL-VL/VR/VC installation testing, we evaluated several common distances between the door frame and shelf edge used by refrigeration cabinet manufacturers: 80mm, 100mm, and 150mm.
Under identical environmental conditions and using the same vertical lighting parameters, we adjusted only the installation distance and observed the resulting illumination performance.
The test results showed that when the distance between the door frame and shelf reached 150mm, the lighting distribution became significantly more uniform while maintaining illuminance levels above 2000 lux.
This demonstrates how critical installation distance can be in refrigerated display lighting applications.
Conclusion
The performance of refrigerated display lighting depends on many factors beyond the lighting product itself. Product structure, installation conditions, cabinet design, and light distribution all directly affect the final illumination result.
At Laidishine, we not only provide refrigerated display lighting products, but also help customers select suitable lighting solutions based on real application scenarios. With more than 10 years of on-site retail installation experience, our team provides professional installation guidance and application support to help customers resolve most installation issues efficiently. Now, any interest in our products, feel free to DM me.
