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Add-on LEDs for Solar Day Lamp
High Power Solar Day Lamp
It is a 1 Watt White LED. It provides between 30 to 45 lumens when forward current is 350 mA
What is the light intensity of the SMD LEDs you have used?
Simple Solar Day Lamp which lasts for 15 years
Hello, I saw the comment today,1KW solar setup uses 6 PC 200w Solar panels.The Solar panels have a VOC of 44v, Two such panels are connected in series for VOC of about 90v. The MPPT Charge controller I used can take VOC upto 150v. Now, 3 such series sets are connected in parallel. Now effectively we have a 1200w Solar array with VOC about 90vThe MPPT charge controller converts 90v to about 27v as required to charge 2x 12v Inverter batteries. In doing so, it reduces the voltage but boosts the amperes thats the beauty of MPPT. I am using systellar 4 stage MPPT that was custom ordered and can charge batteries with upto 40A as required.The Final output of this system is about 1KW as measured at the battery (accounting for voltage drop, Conversion losses, heat losses etc)
dear bhvm could you please detail us the 1KW Solar setup with MPPT charge conroller(2x12v)
Dear diy_blokeYour question is very valid. A 12 V PV panel actually has a voltage rating of 17 V at maximum power. It has an open circuit voltage of about 20V. Why it is called as 12 V PV panel, my guess is, it is used for charging 12 V battery. The 15 ohm resistor is designed as a worst case value. In summer the panel may generate much more than 5 W of power. That is because, 5 W rating is specified at standard condition of 1 kW solar power per 1 sq meter area. In summer the solar intensity goes well beyond that. Which means the PV panel may supply more than 19 V at full load. Taking this into account 15 ohm resistor is included. Normally, the LED current is in the range of 150 to 250 mA range. This provides good light output. If more light is required kindly see the article "High Power Solar Day Lamp" in instructables. Usually, the life of LED depends upon the current flowing through it. So, if lower current is flowing through the LED it will have longer life.Lastly, even during cloudy days with sufficient light, these PV panels do generate good open circuit voltage which is greater than 15 V. Hence the LEDs will always be forward biased and will be ON. The intensity of light from LEDs may be lower. Until the sunlight intensity goes very low such as in the evening, we keep getting light from the LEDsI hope I have clarified to your satisfaction.Thanks-Abhijeet
Dear diy_blokePlease have a look at one more add-on feature for solar day lamp at following link:http://electronicdesign.com/power/solar-day-lamp-also-powers-fm-receiverThanks-Abhijeet
Dear diy_bloke,Please have a look at one more feature for day lamp at following link:http://electronicdesing.com/power/solar-day-lamp-also-powers-fm-receiverThanks-Abhijeet
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