The variable message sign applied in the highways is a kind of LED induction screen erected above the highway or on both sides of the road. It is generally composed of single and double color LED display screens, which are connected to the traffic management system to release some preset information or real-time traffic information, and some small LED information boards could post simple text prompts, such as speed change sign and lane change sign. The reason why it is called a variable message sign is that compared to ordinary information boards, the information on this kind of LED information board with integrated control systems can be freely replaced and changed.
The main purpose of the highway variable message sign is to publish some textual information. Generally, the traffic information, road condition, safety reminder information, weather information, road closure and construction information, and some unexpected real-time road condition information. There are also some large propaganda information boards that could even play videos. Its core purpose is still focused on the dissemination of information.
The LED panels commonly used in large variable message signs in highways are P20 or above, small and medium-sized information boards are normally P10 or above. The specific specifications could be adjusted according to the actual situation. The parameters are all just reference and all those can be adjusted according to the actual situation and customization.
Even the highway variable message sign is a kind of LED display, it is far from an ordinary outdoor LED display. The technical difference is very big. First of all, the protection level is quite different. The protection level of the highway variable message sign is IP66 or higher, windproof and rainproof and it has to work non stop without failure. In addition, it has to deal with the resonance of large vehicles passing by. Vibration of intensity is also an important factor affecting the service life of the variable message sign. Shanghai Sansi has made significant improvements to this type of variable message sign, including the application of a patented double-door cabinet and a patented energy-saving LED light set, along with an internal patented constant environment detection control chip.
The technical requirements of the highway variable message sign are also strict, because the core of the LED display is the LED diode and the quality of the diode directly determines the service life of LED display. The LED modules of Shanghai Sansi variable message sign are self-produced, and the light-emitting diodes are all branded products from top manufacturers in the industry, and thus it in a way ensures the quality of the products, and to a large extent maximize the servie life of the products.