Will Your LED Lighting AC/DC Power Supplies Survive in the Real World?
LED lighting project success depends on choosing the right manufacturer.
When it comes to the success of your LED lighting project, let the salesperson know you’re going to be watching carefully to make sure their LED lights are up to the task.
In our last article, Is your LED lighting project headed for failure, we examined the importance of the light engine in assuring LED light reliability. Heat ratings are a critical consideration. But don’t rely solely on spec sheets for rated temperatures. If the lights come from a cheap overseas supplier, there’s a good chance their spec sheets may not tell the whole story. It pays to do a little fact checking. Ask the salesperson for the junction point temperature of their LED board at a room temperature of 68° F and the rated temperature of the LED chip (not the rated temperature of the fixture). Adding these two figures together gives you the actual rated temperature of the fixture. That way, you can verify if the heat rating indicated in their specs is accurate or not. Once you confirm that information, be sure to consider the other part of the LED lighting reliability story.
The AC/DC power supply is the weakest link in your LED lighting.
Many people don’t realize that LED lights don’t run on your building’s alternating current. They are powered by direct current. As a result, an AC/DC power supply (also known as a converter or driver) takes your building’s AC and converts it to DC – at a specific voltage or specific current depending on the LED board design and the LEDs used. Regardless of which type of converter and LED combination, the driver is the leading cause of LED fixture failure and therefore deserves your attention and due diligence.
Like the LED light engine, you want to evaluate the design and components of the driver. In the case of the light engine, the LED junction point temperature pretty much tells you everything you need to know about the LED and the LED board. But unlike the light engine, the driver is a lot more complicated.
Drivers are easy to make, but ultimately, you get what you pay for. Based on our experience with a wide range of manufacturers, we recommend staying away from LED manufacturers that build their own drivers. In theory, all you need to do is create a circuit board with one-way diodes. Manufacturers can make one for as little as $10 and it will work in a test lab. It’s a tempting alternative to a leading brand name that can run as much as $75. For the manufacturer a cheap driver is a quick route to better margins, but they’re also quick to die.
We can tell you from experience, cheap drivers fail in the real world – quickly. If you spoke with electrical distributors as often as we do, you’d know their biggest risk is not LED manufacturers standing behind their warranties. It is LED manufacturers being in business long enough to give you an opportunity to exercise the warranty. And cheap drivers are a big part of the problem. When it comes to drivers, that’s why we recommend sticking with one of the big four – Inventronics, Meanwell, Philips/Advance or Thomas Research. After all, Inventronics has been in business for 25 years for good reason.
Thermal efficiency of LED lighting fixtures and operating environment directly impact driver reliability.
You don’t have to have high-heat environments for heat to kill your fixture’s driver. And if heat kills your driver, it can kill your LED fixture in the process. One of the fatal design flaws of so many LED lighting brands is that the driver is internally mounted directly above the light engine. In those designs, the LED light engine easily can produce enough heat to prematurely kill the LED driver even in room-temperature installations.
For maximum protection of the driver and the fixture, the driver must be installed in a place that is not directly above the LED light engine and the driver needs to have a dedicated heat sync to reduce driver operating temperature in any ceiling that gets above room temperature.
So often, companies tend to think about the facility floor when taking temperature into consideration. But you need to be thinking about what’s really going on at the ceiling level.
After all, heat rises. So, if the space is temperature controlled to 70° F, the ceiling temperature could be considerably higher. In many manufacturing facilities, the roof is also just above the ceiling and there tends to be a lack of adequate insulation. If that sounds like your facility, the sun will actually overheat the air at the ceiling level, creating an LED driver killing temperature that turns your newly purchased assets into liabilities.
For these reasons, we highly recommend getting reliable temperature readings at the ceiling level for an extended period of time. You want to be sure you know what you’re dealing with when it comes to your ceiling temperatures. The life of your drivers and your LED lighting fixtures depends on it.
We also recommend going with remotely installed drivers wherever possible. It’s been our experience that this configuration protects the driver and the fixture from unwanted heat build-up, extending the life of your lighting investment. Remotely mounted drivers also provide another valuable benefit. Since these designs can easily last 10 years or more, they make it easier and more economical for you to adjust lighting placement to keep pace with changing facility floor requirements. If equipment is moved or replaced, you probably will want to relocate light fixtures to provide the optimum light levels on the facility floor. With remotely mounted drivers, that process is as easy as moving the light and simply replacing the power cord with one that’s a more appropriate length. There’s no costly and time consuming regridding involved.
To help you successfully navigate the numerous technology options available to you, our next installment looks at how to measure LED light engine temperature, driver temperature and room temperature.
For more information about how to ensure the success of your high-efficiency industrial LED lighting project, get all the skilled professional resources needed and maximize the project’s benefit to your organization, contact us today or visit wasmerco.com.