What is an outdoor LED sign?
Any display that is mounted outdoors, that has an active display area made of light-emitting diodes (LEDs), is technically an outdoor LED sign. But there are special factors that make LED signs work best in outdoor settings.
To be effective outdoors, LED signs need to:
Compete with the brightness of the sun – Nit ratings are used to describe the brightness capabilities of LED signs. The sun registers approx. 2,500 Nits, so any sign should be able to compete with this rating at a bare minimum. Higher Nit ratings are indicative of longer-lasting diodes since they degrade over time.
Combat the elements – LED Sign cabinets should be made of aluminum to avoid oxidation, should be painted or powder coated with industry grade materials, and any seals should also be made of high-quality materials and adhesives to provide longevity.
They must mitigate risks related to humidity and heat – Heat risks are mitigated by either active methods (ie fans with rear or front ventilation) or passive methods, like heat sinks for example.
Water infiltration is mitigated by providing quality seals in seams where seepage could otherwise occur. Many signs also have either conformal coating (a thin layer of impermeable coating applied to circuit boards etc) or silicone potting which is used to completely seal LED modules. Potting is best at keeping humidity at bay due to its thickness and flexibility when submitted to temperature changes.