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  • Build your own Variable Lab Bench Power Supply

    Resistors takes whatever it needs and buck converter feels it doesn't need anymore and automatically keeps the voltage down. That's what a buck converter is and does.

    I meant to say buck converter REGULATOR. That's what it does, it not only converts DC to DC, but it also regulates voltage or current. Very good explanatory video on buck converters regulators:https://youtu.be/77vxOF2V-xU

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  • Build your own Variable Lab Bench Power Supply

    It looks like your 3.3 Ohm resistor is not capable of drawing enough current and there is no need for voltage to go up. Most of low resistance resistors are only 1W, 3W or 5W limited. It looks like you have a 5W resistor, hence at 5V it only draws 1A.Connect a 12V 55W car headlight bulb if you want to test the power supply. It should draw around 4.5A of current, just below the maximum rated PSU current.

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  • ARDUINO MPPT SOLAR CHARGE CONTROLLER (Version-3.0)

    There is no current readings on the battery side in this project. Therefore you cannot properly calculate wattage going into the battery and have a proper efficiency reading. But maybe author did not care about efficiency reading, I don't know. Maybe he felt confident to believe his system is very efficient. I shall add a current reading sensor on the battery side and will calculate the wattage and efficiency.As for the battery charging... I think it's not priority in this project as batteries are almost always full. But what if you connect a dead battery? It would take days to fully charge a dead 12V lead battery.

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  • ARDUINO MPPT SOLAR CHARGE CONTROLLER (Version-3.0)

    Hey. I am very excited about your project and I am planning to build one myself for slightly smaller solar panels. I really like you included the formulas, calculations and even article papers for more information. I am learning a lot from this.But I have one question. Looks like rated voltage is 12V. That is a voltage to charge the 12V battery. However, most of the time a higher voltage is used because it forces the charging reaction at a higher rate. Charging at the minimum voltage (12V) will take a long long time. It is recommended to us 14.1-15V to charge a 12V lead battery:http://www.powerstream.com/SLA.htmThat's how they are charged in cars as well. Alternators charge them with 13.6-15V.What is the voltage you ended up after the buck converter? Is it more than 12V?

    Alright, it make sense. But measuring the voltage going into the battery is necessary. How else are you going to see how efficient your system is?You measure the voltage, current on the solar panel side, calculate the wattage.Simultaneously you measure the voltage and current on the battery side, calculate the current. Then you divide battery wattage/ solar panel wattage and here is your efficiency. I think this is one of the most important aspects of the system.And I could not find where author is measuring voltage current on the battery side. It would be identical to the ones on the solar panel side. In addition, this would server as a safety feature as you would actually see what you are putting into the battery real time. Now, you may just guess that buck converter is rising togethe...

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    Alright, it make sense. But measuring the voltage going into the battery is necessary. How else are you going to see how efficient your system is?You measure the voltage, current on the solar panel side, calculate the wattage.Simultaneously you measure the voltage and current on the battery side, calculate the current. Then you divide battery wattage/ solar panel wattage and here is your efficiency. I think this is one of the most important aspects of the system.And I could not find where author is measuring voltage current on the battery side. It would be identical to the ones on the solar panel side. In addition, this would server as a safety feature as you would actually see what you are putting into the battery real time. Now, you may just guess that buck converter is rising together with the battery and don't have a clue what the amperage is. You just know it's limited to 5A.

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