| T O P I C R E V I E W |
| kaycee |
Posted - Mar 06 2014 : 8:31:56 PM
Hello. I'm just thinking what is the output power of this circuit and how will it take to fully charge the battery? Thanks. :)) Please help me.
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| 15 L A T E S T R E P L I E S (Newest First) |
| pebe |
Posted - Mar 25 2014 : 7:30:15 PM
I have explained it all before. Go back and re-read it. |
| kaycee |
Posted - Mar 25 2014 : 7:21:38 PM
Is it okay that the only output of the original circuit is 9V without battery yet?
When the charger reaches the right amount of voltage, i will turn R2 to min or max? Thank you. |
| pebe |
Posted - Mar 25 2014 : 7:16:38 PM
It looks like he has faults with the circuit he has built, and it might be far safer to ensure it's working properly first, before he connects a battery!
Can you explain the 'weird inverse resistive load of a lead acid battery'? I was taught that its equivalent circuit is a voltage source equal to its EMF, in series with its source resistance. Nothing inverse about that. |
| Aaron Cake |
Posted - Mar 25 2014 : 5:20:57 PM
Honestly, what's wrong with following the instructions on the circuit page?  That's what all those notes are for. They tell you how to adjust the circuit. While a capacitor will do the job, it can't simulate the weird inverse resistive load of a lead acid battery. Stick a battery on the circuit, connect up a voltmeter, and adjust the pot until the LED lights solid at the voltage you want the battery to charge to. The LED will begin to blink as you approach that voltage. |
| pebe |
Posted - Mar 25 2014 : 12:38:43 PM
Does it light? |
| kaycee |
Posted - Mar 25 2014 : 10:51:23 AM
what will i do if the LED does not light? |
| pebe |
Posted - Mar 25 2014 : 10:39:35 AM
Ignore what I said about R6. I did not have the circuit in front of me when I replied, and I assumed that R6 connected to Q2 anode, but it does not.
Short out anode and cathode of Q2 as I said before. The LED should stay lit as long as you keep them shorted. |
| kaycee |
Posted - Mar 25 2014 : 09:28:48 AM
I thought you said I'm going to short anode and cathode of Q2? Am I supposed to short that or not? Both end of R6 will be shorted and connect it to the ground? |
| pebe |
Posted - Mar 25 2014 : 07:24:45 AM
The LED should not just blink. It should stay lit as long as you are shorting the bottom end of R6 to ground. Does it? |
| kaycee |
Posted - Mar 25 2014 : 06:24:32 AM
I already shorted the anode and cathode, the LED blinked only.
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| kaycee |
Posted - Mar 25 2014 : 05:49:54 AM
I dont know when to adjust R2. :(
I will short out the anode and cathode of Q2 and i will turn on the charger connected to the 220V?
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| pebe |
Posted - Mar 24 2014 : 12:13:42 PM
The peak voltage of your transformer is 1.4 x 12VRMS = 16.8V. So allowing for the voltage drop of D1 and Q1, the voltage your reading is pretty much what I would expect.
Re the LED not lighting. Short out anode and cathode of Q2 to ensure that the LED is workjng correctly. If OK, look again at my post of March 19. It's not lit because Q1 is still trying to charge the cap. Have you adjusted R2 correctly? Turn R2 so its slider goes toward the end that's connected to R1, then wait a few seconds for the cap to discharge. Will the LED now light. If not, measure the voltage across the 100µF cap. What is that voltage?
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| kaycee |
Posted - Mar 24 2014 : 10:14:07 AM
I already made the circuit in the pcb, the output of the original circuit is 9 something but when i put 100uF cap across the output, it is 13 something. How did this happened? How will I explain that the input is only 12V but the output is 13V??
Also,the LED doesn't light. When will the LED turn on? Thank you again. Thank you very much.:))
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| Aaron Cake |
Posted - Mar 19 2014 : 09:45:56 AM
quote:
Originally posted by kaycee
How can I prove that the battery is charging? Thank you pebe and aaron cake for helping. :)
Measure the voltage. It should rise slowly. |
| pebe |
Posted - Mar 19 2014 : 09:35:40 AM
When charging, the LED will be lit very dimly - if at all.
When charged, the LED will be lit normally. |
BattCharger12V.gif