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During power failures and power cuts road users suffer immense difficulties due to non-availability of traffic signal lights all over the world. Use of solar cells with lead acid accumulators to provide required power and the use of light emitting diode (LED) displays to function as signal lamps to reduce the stored power consumption will be a feasible solution for the same. Since the LED display consists of a number of LEDs, visibility from side ways is better than the conventional signal lamp having a single light source. Failure of the lamp in the conventional signals halts the entire operation of the signal lamp but in the case of failures of few LEDs in a matrix will not cease the entire operation. In most of the LED display traffic light systems, set of LEDs will not illuminate even when only one of the LEDs burnt out since the set is connected in series. In this design, parallel sets of LEDs are connected in series, and therefore, only the defective LEDs will not be illuminated but all the others will be illuminated. Some major advantages of this system are uninterrupted operation around the clock throughout the year, very low maintenance cost for replacing LEDs and the lead acid batteries, and during the installation of new signal posts it is possible to erect the same as a wireless installation. Solar panel with an accumulator can provide power while infrared sensors and diodes could be used to transfer signals between each signal post, hence it is not necessary to dig across the road for control and power cables. For the safety and the convenience of the pedestrians and vehicular traffic, bi-color seven segment digital displays are available to indicate the waiting time and remaining moving time. Considering the signal light requirement for a country, the above solution will have a considerable impact on the national power grid |
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