10 Tips to Qualify your LED Tube Lamps

Well, before jumping into any details, don’t forget why you  retrofit LED tube lamps. Saving energy? Yes. ROI? Yes, but even more important is, you are buying “light” for the “eyes”, and you only have one pair of eyes. Qualities do matter.

1. LED chips : Make sure your LED chips are qualified. They need to be LM80 certified, refer to the link for details:  Poor LED chips could generate harmful blue light. The light output could decay fast.  The light color could shift and make you feel dizzy.

2. No LED Hotspots : Most users feel uncomfortable looking at LED hotspots. In order to achieve even light distribution, the lamps need more LEDs inside with good light diffuser.

R17D ETL approval 120lm/w led tube 8ft 48w

In order to achieve low temperature, we need 1) LEDs are under-driven. 2) Good heat sink/dissipation. 3) No internal LED driver inside the tube lamps.

5. Under-driving LEDs:       In order to achieve low temperature, the LED chips need to be under-driven. For instance, in a Luxul T8 4ft tube lamp, there are 90 LEDs with each LED of 0.5W rating. So the rated power for the whole tube is 45W. Since it is burned as a 16W tube, the tube is 3 times under-driven. Under-driving not only helps to reduce the LED temperature, it also helps the energy efficiency, i.e., lumen per watt (lm/W). So always check with your vendor the LED ratings and the real power they burn to calculate the ratio of under driving. Never buy a LED tube lamp which is Over-Driven, e.g. rated at 20W and burned at 22W. The LEDs would age quickly and temperature would be high.

6. lm/W : Don’t be misled by the light output per se.  Consider the consumed power also. A good LED tube lamp should perform 100 lm/W to meet DLC qualification. Please check  for details. Typically there are two groups of user flavors: 1) high lumens for high bay applications, and 2) low power for rebates from utilities companies. For the first one you might need 2300 lumen tube with 23W. For the second one you might need 1500 lumen to consume 15W to get more rebates.

7. Heat sinks: heat sink is used to take the heat out of the tube lamp. Some vendors, due to the cost down concerns, use whole plastic tube lamp and plastic heat sink. But metal (aluminum) is still the best heat sink for LED tube lamps.

8. External Driver/Ballast : Never use internal drivers which are embedded inside the tubes. They will increate your LED temperature significantly. In general, the power conversion from AC to DC generates at least 10% of heat. For instance, if the total power of the tube is 20W, at least 2W of heat will be generated. You would rather this heat is generated outside the tube, instead of inside the tube. There are two options to use external driver/ballast: 1) replacing the old ballast with a brand new driver or ballast, or 2) using the existing ballast to save your labor cost.