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UPS Charging problem due to load shedding

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asimraufawan

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I am facing a problem related to UPS i have 600 Watt ups with 148AH battery, due to electricity shortage in my area i m facing 12 hours of load shedding in a day therefore the ups is unable to charge the battery in the available time.

What if i connect separate power supply in parallel with UPS to charge the battery fast the circuit is attached kindly suggest is it possible or not or what other cheap solution i pick to charge the battery fast.

Thanks.
 

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Your concept is good although you will most likely need higher current output from your transformer.

And you can omit the capacitors, voltage regulator and single diodes. Batteries are not fussy about the charging waveform. Incidentally a 12V regulator would only charge the battery to 12V and no higher. It ought to go up to 14 or 15V by the time it's fully charged.

The led can stay since it's an indicator.

Your battery is 150 AH. To charge it in, say 15 hours, you'll need 10 amps going into it for all that time. This is a C/15 rate which is typical.

You can use an 18VAC transformer and it will still work.

Even an 11.5 VAC will deliver on the peaks. And it will automatically taper the charge as the battery reaches full capacity. Charging will automatically stop at VAC * 1.414. Minus 1.2 V diode drops through the bridge rectifier. This equals 15 V. A typical end-of-charge voltage for a lead-acid battery.

After all that... it may be more practical just to use an automobile battery charger.
 

i think C/3 will also do the job, the rest is same as BradtheRad mentioned. indeed an automobile battery charger will do the job.
(*** bless WAPDA for its remarkable service)
 

increase the charging current and volt, for 150AH battery you can charge @10-15A current
 

@asimraufawan
you have a 150 AH battery shown in the sketch, therefore you need 1/10th amps to charge the battery, so it comes to 15 amps initial charger current
LM7812 is a 1 amp rated regulator so it will not work, more over you should have selected a LM7815 regulator which would have given 15V-0.6V diode drop=14.4V to the battery
it will take all day and still the battery will not charge with this circuit
From ups side also you should give a 1N5408 diode to stop external charger current from going into the ups
better to search for SCR type 12V car battery charger in Google
**broken link removed**
 

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