I found that my UPS is not giving sufficient back up as expected for 20 minutes. I thought that I have to spend Rs. 800 to replace the battery. But I was not in a hurry. Want to find out the reason. After 5 minutes, the PC shutdowns. Why so? The UPS battery is not giving sufficient power (Ampere Hour) to run the load. The UPS battery is a 12 volt 7 Ah (Ampere hour) Maintenance free Sealed Lead – Acid battery (SLA). That means, it is “Maintenance free” and can be used for long time without any attention. But what happens is, the cells dry out due to heat generation. This happens after 6 months to 1 year of use . It is a Lead Acid battery that requires Electrolyte in the cells. So water is necessary inside. It has 6 individual cells giving 2V each. After removing the battery from the UPS, I found that it is very easy to rejuvenate the battery through “Hydration”. The battery will become top, if the dry cells are filled with battery water. Hydrated the battery and charged. Well, now it is giving more than 15 minutes back up. Saved Rs. 800 and reduced an e-waste. You can also rejuvenate the 6V Emergency lamp battery like this. So do it yourself. It is only a 10 minutes job.
Category: Science
Wow! We can make a cup of cold water in 5 minutes without a Fridge. You need only a Peltier Element, a 12 volt high current battery and a Computer cooling fan. Peltier element is a semiconductor plate like device with Cold and Hot sides. When we provide 12 -18V, 1 amps power to it, one side of the Peltier suddenly cools and the other side turns hot. The cool side temperature goes down below 0 degree and the hot side becomes around 100 degree. So to transfer that much heat, the Peltier should be placed over a large Heat sink. A Computer cooling fan with heat sink is the best choice. Fan will remove the heat from the Peltier and heat sink. At the same time, the cold side turns too cool in minutes. Without a heat sink, the Peltier will be damaged. If we reverse the Polarity (+ and –) of the power supply to Peltier, the sides reverses. That means, cool side becomes hot side and vice versa. Let us make one Peltier Fridge to get some cold water. Later we can change it as a heater to drink hot water. Peltier costs around Rs.200.
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Why wasting electricity for charging USB devices including Mobile phone? Sun is there to give power for this. Install a Solar Power Outlet in your home to harvest solar power for charging all USB devices in day time. Its cost is only Rs.500 and you get unlimited day power for more than 25 years to charge all USB devices. The expensive part of the project is Solar Panel. A 12 Volt 5 watts Solar panel costs around Rs.400 because the current rate is around Rs.80 per watt. The remaining components costs only Rs.100. So by spending Rs.500 initially, you can charge all your USB devices at the expense of only 6 Paisa per day . The calculation is for 25 years (50,000 Paisa / 9000 days = 5.5 Paisa). So hurry up to make this project.
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