Photo: The Accelerated Product Life Test Labs at Current
Authored by Robert Spivock, Director of Technology, GE Current, a Daintree company
With more and more players entering the horticultural lighting space, it is essential that you trust a major lighting company with this critical part of your farm. You’ll likely have plenty of companies—from new and unproven to trusted and acclaimed—vying for your attention, all promising the best and brightest lighting solution. They’ll probably throw around buzzwords as well, all the while assuring you that they have a powerful light that will move your farm forward.
But lost in all the talk about light spectra and power is the light’s reliability. Too many people take the long lifespan of LEDs for granted without considering drop-offs in quality. A grow light can be trusted to turn on, but for how long? How long will it maintain its light levels? Will the spectrum change over time? Can it withstand the thermal loads of a greenhouse?
Ultimately, growers need to ask: What does it mean to be a reliable LED fixture? And how can you distinguish a reliable fixture from an unreliable one?
To the team at Current, reliability means quality over time.
The thing is, what makes a “quality” LED grow light is different to each grower. Quality is about all the things that are important to the customer, whether they talk about it or not. It’s like a car with no steering wheel—you rarely ask for a steering wheel when buying a car, but you would be unhappy if you didn’t get one.
Designing Reliability from the Beginning
When designing a new LED fixture, you need to understand the environment it will be in, as well as what the customer asks for and expects it to do over time. The environment is the first factor, and it contains a number of conditions that should be considered when selecting or designing an LED fixture—water, chemicals, sun, insects, operators and manufacturing equipment, to name a few.
Other things to consider include electrical surges and electromagnetic noise. While these may not be thought of as traditional components of a grow space, they could have a major impact on the state of your environment and the functionality of your lights.
Building Quality into LED Fixtures
At Current, reliability is intertwined with our new product introduction process. As we design and build new lighting products, we follow a rigorous process to ensure the LED fixtures meet our customers’ quality standards—both what they do notice and what goes unmentioned.
Step 1: Set clear targets based on customer needs and product environment.
You can’t build a superior product without understanding the factors that will be most important to the customer—in other words, what elements are going to make it a quality product. Get to know the grower, the crop and the growing environment to determine what characteristics will be most important.
Step 2: Translate those goals into numbers and statistic-based objectives.
The next step is turning those important qualities into measurable quantities. For example, if a customer has an objective of a quantity of light over the life of fixture, it could be translated into an end product rated L90 over 36,000 hours.
Step 3: Design reliability into the product through component derating and predictive analysis.
Derating is choosing high-quality components from proven vendors and using them in a design that does not stress them to their limit. This ensures that the product can survive for more time and under stressful conditions it may encounter over its life. If a component typically sees 300V in operation, it may be rated to 600V.
Step 4: Conduct reliability growth testing to find the weak points in the design.
At Current, we’re always testing our products by taking them to the limit to see how they will function in extreme conditions. This means trials that push the lights to the brink and beyond, identifying any weaknesses. We learn what would give out first and can work to eliminate those issues and strengthen the overall product.
Step 5: Accelerated life testing to show reliability objectives have been met.
Once we have reached a final design, we statistically demonstrate quality over time by doing accelerated life testing.
Our process provides an accurate look at how long the fixture and LEDs will perform and at what level. Providing growers with a realistic picture of what they can expect—rather than only offering a guess or a best-case scenario—helps them make an informed decision about their investment and better plan for the future.