Are LEDs Generic? Aren't They All The Same? Simply Put, NO!
Most buyers do not consider or even understand what really makes a creditable long lasting LED package, let alone the manufacturing differences.
By Fritz Meyne, Jr., Vice President Sales, Bitro Group, Inc.
Let's discuss these differences in a somewhat generic way.
Certainly the name is used in a very generic way, to say the least? Everyday analogy: To say a car is a car is more to my point; they both can get you from point A to B, however;
To my question's point, no they are not!
- Different performance. (LED-WPF, Efficacy, strokes, etc.)
- Different style. (Footprint, IP ratings, Binning, etc.)
- Different costs. (LED- the best always costs more - check module spacing as an example)
- Different Costs of ownership (LED-Life Cycle, efficacy, construction, IP rating, chip brand, etc.)
- Different warranties. (LED 3 year labor, 5 year and 10 year product options - buyer beware!)
- Different MPG. (WPF, Efficacy, Under-driven or over-driven? Think VW MPG worldwide fiasco)
- Different value now and especially later...the differences go one and on!
While universally there are not many actual 'chip' manufacturers, like everything in our world today, there is more to consider than what meets the eye, so to speak. Add to this factor, that most buyers do not consider or even understand what really makes a creditable long lasting LED package, let alone the manufacturing differences. Let's discuss this in a somewhat generic way.
LED. An acronym for Light Emitting Diode and is only a part of the lighted 'package.' So let's discuss the basic LED package for the sign market. For example, you see a module vendor offer 'Brand X' chip set. You assume that brand name means the total module / package. Wrong! Wrong and wrong!
The components seem simple:
- Chip the part of any "package" that actually emits the illumination. Tremendous variances here can make or break your effective light beam, your color matching and more. Better chips do cost more!
- Binning this is a method in which all LED are separated into various bad to great categories to support consistent color and electrical continuity. This is also a cost factor!
- PCB Printed Circuit Board, and this can make or break your Life Cycle benefits also. Copper is used to provide the electrical conduit if you will. The ability of the Chip and wire to properly "connect" varies tremendously between manufacturers. Single sided copper coating to double sided is but one engineering consideration of a better vs. OK package. Again better costs more!
- Chase The main component used to get the power distributed through the "package." Also part of the PCB.
- Ma Millie Amp is a reference to the actual current going to the "chip." Typically lower grade chips or chips outside of the better binning will need more ma applied for performance relative to better binned chips. Better chips with better binning can more easily be under driven, which also adds to realistic Life Cycle advantages. As in the real world, "better" costs more! Marginal chips with more applied ma does shorten relative Life Cycle advantages. What is that worth to you?
- CCT/CV CCT is an acronym for Constant Current Technology where the electronic circuitry, in overly simple words, guarantees each CLM gets the same voltage, guaranteeing near identical brightness in the total run. Think of modern A/C ducts and how they change diameters or volume over long lengths to keep the air flowing properly and evenly. CV is Constant voltage, this is the more or less first generation type of circuitry where you have to understand there is XX voltage drop over longer lengths and you have to segment your CLM quantity, so that all runs are divided up as equal as possible. To illustrate, the first CLM will be the brightest and the last one might be slightly dimmer. A/C ducts in the distant past used the same size ducting and thus the exit point closest to the "unit" provided a lot more air flow than the one at the other end of the house. This is not to say CV is a bad choice, but you do have to understand how to use it correctly.
- Solder is used typically to connect the wire to the positive and negative connections on the PCB. This is a critical connection and as you might guess, there are decent solder connections to pretty bad ones. If you have never removed your "cover" you should, it might scare you!
- Thru Wire This term refers to the way the wire used between the modules is connected to the PCB. With this method the wire is continuous eliminating potential weak solder connections. The actual connection to the PCB is done with precision screws in an automated process. Does your brand have this option? If you do not know you should find out!
- Wire the electrical wire used from module to module and connectivity is critical. What gauge wire is used? 18 gauge is typical to a more premium package. 20 gauge is becoming the norm to save money...at your expense! Smaller gauge wire costs less and you ultimately get less!
- Body the protective housing encompassing the "package." A critical component to a proper package in how it protects the components. Potted? Potted with what another critical concern. Sealed? How? Dust proof? IP rating? Certainly important for you to truly understand.
- Optics / Beam Angle today most CLM (Channel Letter Modules) have some type of optic to enhance the light spread. However there are tremendous manufacturing differences. Optic material, optic pattern and how they are sealed to the PCB is another very critical Life Cycle issue. Again better is, well better. And an additional concern when using Optics, is if the chip typically has to be a Higher Brightness (HB) chip set as the Optic spreads the light over a much greater area, thus more lumen (brightness) is needed to take advantage of the Optics benefits. If you do not know find out!
Beam Angle started in the sign market at about 90 degree, then progressed to 120 with the advent of SMD type chips and now we have optics, typically around 160 degrees. I see SMD chips w/o optics advertised at 140 to 160 and that is just not true!
- Heat the "package" contains all of these parts (and some more) so evacuating the heat from the PN junction (Positive and Negative) is critical as is the size of the PCB and Trace if engineered correctly will help to pull the heat from the P&N junction where temperatures in our industry can reach 70 degrees C. Heat evacuation and proper engineering does cost money! Additionally proper engineered heat evacuation increase the life of the module in total. Improper does just the opposite it decreases the life.
So what does this simple (believe it or not) information overview actually mean to you or what should it mean to you?
- LED are not created equal, you get what you pay for, or worse what you did not pay for!
- All CLM are not created equal, again you typically get what you pay for.
- Lumen brightness. Look at every vendor...a wide variation of lumens between similar type modules. Why? It is easy, it is the individual testing (remember no fixed testing standard in our industry). Thus one "great" lumen number might have been tested at fractional initial power where there is an initial spike of brightness. Others rest after so many seconds for a real world number. Again the variation can be and is often "Apples and Oranges" at its worst!
- Remember an average warranty in todays market is from 3 to 5 years and it is not the free warrantied CLM that is your risk. It is your reputation and the costs to replace such a low cost item! Only you know what that might be worth. Most warranties for actual (optional) labor are "exclusionary" type warranties, so buyer beware. Even hardware warranties can be exclusionary. Read and understand your warranty.
- Buying form a pure importer while in itself should not be a risk, there are so many factors that at minimum suggest there are risks. With so few worldwide "chip" manufactures, your real risk is "Who Are You Doing Business With?"
There are so many products out there sold under numerous "brand" names it certainly can be confusing.
- Who are they buying from?
- What brand "chip" are they using?
- What K temp range are you actually getting?
- What binning range are you getting?
- And to be overly fair, a Brand name in itself does no guarantee any given product is the best or right for your needs. Do your Home Work!
- Another very important factor in the Sign Industry (unlike the Lighting Industry which does have exact testing standards) there are NO testing standards in the Sign industry...you always get the proverbial "Apples and Oranges" comparison. So where do you, your needs and your customers fit together? There are national brands over-promising (bad for you) and national brands under promising (good for you as they offer real world test results, not optimal in the "lab" testing).
- Something else to check that can be very critical to your overall "job" costs, is to look at each manufactures modules per foot and row to row spacing. Are you really going to do your layout based on 1.6 or whatever uneven number suggested? I doubt it, as easy always wins over complicated, especially in the sign industry.
- And watch your vendors "stroke" recommendations. Extreme strokes like 18" coverage sounds great, however you are more than not getting poor overall brightness. There is a point of diminishing return at every turn.
In closing, in my humble opinion and decades of experience, in the simplest way to explain all of this "You Get What You Pay For!" Economics wins every time and finding the best mix of all of this is seriously time consuming. Although I did not touch on price, the variation from what I call B&M (Brick and Mortar) companies with a true US presence (not simple importers) the price range is somewhat acceptable. Again you have to check your data / specifications and look for common variances and decide what those variances actually mean to you in the real world and the value you place on your reputation!
Fritz Meyne, Jr
Vice President Sales
Bitro Group, Inc.