The Pitfalls of Comparing LED Panel Lights Based Solely on Data Sheets

You're likely familiar with the influx of LED panels and general LED lighting options flooding the market. Often, the specifications you see on their data sheets originate from tests done on a single, factory-perfected "golden sample". The trouble is, the actual products you receive might not consistently meet the same high standards as that initial test sample.

This has been a common tactic for some LED lighting factories for a while now. The market in China, for instance, has manufacturers producing professional-grade LED lighting alongside those aiming to revive the replacement market. These factories often present their products as similar or equal to higher-quality options, but the reality can be quite different from what's declared on the data sheets.

One straightforward method some factories employ is to drive the LED chips harder. They achieve this by using fewer chips but increasing the milliamps. This generates more heat, which in turn reduces the overall lifespan. Research indicates that an 11-degree Celsius rise in LED chip temperature can lead to a 57% drop in the expected useful life of the LED. The link below highlights the detailed case studies An Alternative Lifetime Model for White Light Emitting Diodes under Thermal–Electrical Stresses Essentially, by increasing the heat on the LED chips, some factories are influencing when they will fail, aiming to stimulate the replacement market. Based on these figures, it's not difficult to calculate the precise heat needed for a fitting to fail by a certain percentage shortly after its warranty expires, whether that's one year or five.

Consequently, these factories don't always need to use top-quality components like drivers, LED chips, optics, electronics, diffusers, or heat sink materials designed to last for the full expected lifespan of over 50,000 hours.

A recent study explored whether you could reliably compare LED panels using the "similar or equal" criteria based on data sheets. A DIALux simulation compared several major lighting manufacturers. For the simulation, a room measuring 30 metres by 30 metres with a ceiling height of 2.8 metres was set up. The study aimed to determine how many fittings would be needed to achieve 500 lux. This was tested on both 600 x 600 and 1200 x 600 LED panels, all with similar wattage and a declared lumen output of roughly 120 lumens per Watt.

Using the 600 by 600 LED panel, the following results were observed:

Manufacturer	Number of fittings required
1	99
2	120
3	124
4	133
5	138
6	144

The varying results stem from the LED chips used, optics, diffusers, beam angles, glare control, and whether the data declared was for the light source lumen or the fitting lumen.

The implications of this experiment are significant for both the end-user and the approving engineer.

Consider hospitals, where very specific minimum standards exist for each functional area, such as wards, passages, emergency rooms, consultation rooms, theatres, recovery rooms, or administration.

If, for instance, the product from Manufacturer 1 was used to determine the required quantity, and the contractor then procures panels from Manufacturer 6 claiming they are similar or equal (based on the data sheets), the final result could be non-compliance with the determined standards. In this scenario, the contractor would need to increase the number of fittings by 44% to achieve the specified lux levels.

This leads to an increase in labour, cabling, wiring, plug points, fittings, and a 44% rise in electricity consumption.

Therefore, it's clear that LED fittings cannot simply be compared based on their data sheets. If you primarily base your procurement decisions on price, you might find yourself caught in the replacement strategy cycle of fittings designed to fail. This significantly impacts overall maintenance costs and can completely negate any return on investment.

For more information, please contact our sales office on +27(0)11 4620251, send a mail to sales@genesisone.co.za or visit our website www.genesisonelighting.com