Questions to ask when purchasing an LED sign or display:

1. Are the pixels hardwired directly to the circuit board of the sign, or are the pixels "plug and play?" (also called diode style.) 

Hardwired pixels are old technology and have a significant maintenance and replacement concern.  Because it is necessary to open the cabinet to repair hardwired pixels, the repair is expensive.  Also, hardwired units have a plastic cover over the front which obscures over 30 percent of the light output.  "Plug in" style allows a bad LED cluster to be easily popped out and replaced.

2. How many LEDs are there per pixel?

Discount units generally have 3 to 4 LEDs per pixel.  Modern high output signs have 5 to 6 LEDs per pixel.  Generally 5 LEDs per pixel or more is recommended for optimal daytime viewing.

3. What is the distance between LEDs inside each pixel?

This consideration is also called LED pitch.  It is not a major concern with applications besides video billboard LED displays.

4. What is the pixel pitch?

This is a critical measurement referring to the distance between centers of pixels.  This is a millimeter measurement which determines the resolution of the sign. 

5. What is the brightness range?

The brightness is generally calculated by the number of LEDs per pixel.  Generally, most modern LED outdoor signs have a narrow range of brightness values.

6. What is the viewing angle?

The viewing angle of an LED outdoor display is the total angle from the center of the sign that the message is still viewable.  The narrower the angle, the less time people will have to view the sign as they move past it.  For most street applications, the minimum angle that is acceptable is 55 degrees from the center (or a total viewing angle of 110 degrees.) 

7. What is the viewing distance?

The LED message center should have a viewing time of 7 to 10 seconds.  It is therefore important to select the location for the outdoor LED display based on this concern.  The calculation will vary due to the speed viewers are traveling.

8. Does the LED sign company offer installation?

Most LED sign manufacturers do not offer installation.  LED sign vendors such as United LED Displays install and service a variety of LED signs.

9. Is there a written warranty?

LED signs should come with a minimum of a 36 month written warranty, however a five year plan is preferable.  The best warranty programs charge no upfront fee, and only charge a flat deductible.  Be wary of unlimited or long term warranties.  Generally a lifetime warranty only lasts as long as the company that sold it, so make sure your lifetime warranty is offered by a reputable company.

10.  Who will service my LED sign if there is a problem?

Though LED signs are known for needing little maintenance, it is ideal to ask this question during the buying process.  Make sure you are happy with the answer.