Author Topic: Transformerless Battery Charger  (Read 12689 times)

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Re: where do i go to submit or get an answer..400w
« Reply #33 on: December 22, 2004, 04:54:24 AM »
Kinda just have to look the site over and do some searches, post more info etc...

9600 watts a day? 400watX24hr


About 35amps per hour at 12VDC. One cheapy Wal-mart deepcycle battery is 115amp hours, but if you run any lead acid battery to low on a regular basis it does not last as long as it should. SO drawing it down 20% would be about 23amps and provide longer life.


If you use solar to charge them, you need to get 24hrs power durring the day, maybe 6 hrs of sun. That's 1600 watts per hour charging in 6 hours maybe. Your batteries have to last the other 18hours suppling the power with out charging. 1800watts total, or 600 amps. 23amps per battery = about 26 batteries to get the longest best life out of them, provided you get plenty of sun every day for 6 hrs with 1600 watts of pannels.


26 batteries total amps is 2990amphrs and leaves plenty of room for ocasional sunless days. At 400watts your actually using 800amps per day, so you have the 3day safety margin with out lossing power, though you are drawing them down heavy. And if you only have the required amount of pannels needed to meet daily needs how to you catch back up after a sunless day?


All the same numbers for wind power of course, but then you never know if the wind will blow or how much. But wind is much better as it can be anytime, any amount, and also far cheaper. A bit harder to figure, 400 watt wind gennie blowing 24/7 would mean you only need a few batteries. Wind will never be constant and you need the backup, but for how long or how much is the question here.

 If you have strong winds for only a few hours of the day and calm the rest, then you need bigger or more gennies to make the power then and also more battereis to store it for the rest of the day, plus the safety margin of a few windless days.


Water if stream large enough is available is 24/7 and you wouldn't need many batteries at all if you had a 400watt gennie in it. No need to worry about sunless windless days, maybe a drought though sometime durring the year if not a large steam or river :)


If your planning to use an inverter to power a 120ac device or cabin (whatever) then you have a few losses there. It needs to be larger than all the loads you plan to run at one time on it.


 You can set up a combination of things, solar and wind for charging and also wire in a gas/desiel gennie to start and charge when the batteries drop to a certian level for when you are not getting enough sun or wind, uses less batteries, but then it has to have fuel and also a chance it may not start sometime if this is for unattended use.

« Last Edit: December 22, 2004, 04:54:24 AM by (unknown) »

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Re: Transformerless Battery Charger
« Reply #34 on: February 26, 2005, 12:15:40 AM »
I got to this site on a mission,I was looking to get away from transformers because of a project has limeted space.the charging 12v batt on line voltage could work but limiting over charging is a must because of hydrogen gas is made and is fire/bomb.

A simple relay might be able to work your batterys as a event falure back up to switch on your 12v /110vac inverter system when 110ac is not present.I can post more details if this is help full.I have not found good sound way to extract 5-12dc from 110ac with out transformer.
« Last Edit: February 26, 2005, 12:15:40 AM by (unknown) »