anonymous	Car Battery Charger	Sunday, April 12, 2015 11:03:44 AM
I am a novice but I built this charger and it works just like it's supposed to. I am going to hook this up to a table fan that I converted to a generator and charge the battery on windy days. Great site.
richard	Car Battery Charger	Friday, October 21, 2011 8:11:48 AM
from the power supply the positive and negative of the supply connects to where in the charger? it only has one "IN" where does the negative of the supply go? the ground goes to the transformer right?
leochbattery	Car Battery Charger	Friday, September 16, 2011 5:10:16 AM
I just know more about car battery. Don't over charge the battery or it will damage it.
anonymous	Car Battery Charger	Thursday, September 01, 2011 6:59:10 AM
Can i use a 8amp 13.8V voltage regulator as an input supply for the car battery charger?
Lee	Car Battery Charger	Wednesday, February 09, 2011 3:17:59 PM
what should the output voltage of the charger be? i got around 15 V according to multisim. thanks
anonymous	Car Battery Charger	Thursday, October 28, 2010 8:41:28 AM
hi, when saying "most any lead acid battery" do you mean it will charge a 6 Volter too?
shoaib	Car Battery Charger	Sunday, October 10, 2010 7:04:10 AM
can i use any other diode instead of D1 IN457?help me plz....
Max	Car Battery Charger	Friday, June 25, 2010 1:15:25 PM
Thats a great circuit ! I am gonna use it as a storage battery charger. Thank You
siamak	Car Battery Charger	Sunday, June 20, 2010 11:41:25 PM
the circuit that u suggested has 18v input i think it should be DC voltage and as you know a 12v AC transformer after passing throgh a diode bridge give 18v DC( 12x2 root squire). so i think a 12vAC transformer with 3 amp current are enough for this circuit, is it ok?
Spooge	Car Battery Charger	Friday, May 28, 2010 8:38:17 AM
Nice circuit. what needs to be changed if i want to make it charge a 140 amp battery quckly. I need a 10A to 20Amps charger at least, For my ups, we get 4-5hrs blackout here every day.
fabieville	Car Battery Charger	Tuesday, March 16, 2010 7:57:01 AM
how do you wire several LM350's in parallel to use with this circuit? I tried wire 3 in parallel but it didn't work. So can u either show me a circuit with several wired that can use in this circuit or just explain as to how to do it please.
mojtaba	Car Battery Charger	Wednesday, March 10, 2010 2:45:25 PM
can you Substitute R1 500ohm with a 510? and R5 230 with a 220 i am unable to find them. thank you
gajah_gendut	Car Battery Charger	Wednesday, February 03, 2010 10:22:10 PM
for higher current about 5A, you can replace U1 with LM138/LM338
georgi	Car Battery Charger	Wednesday, January 20, 2010 2:24:24 PM
R1 1/4W ??? Out 3A R7 10W ???
baraa	Car Battery Charger	Friday, January 08, 2010 6:47:26 AM
what is the current output rating of this charger? cuz all of these equipment have current rating of milli amps i am an electrical engineering student but i haven't dealth with car batteries much, are all of them 12V (i mean to ask about the output voltage rating) thx a lot
brockster	Car Battery Charger	Monday, December 07, 2009 11:17:37 PM
@Woody: Oops, my error. The LM350 limits the maximum charge rate to 3 amps, not 2 amps. Running at 3 amps, you will need to heat sink the LM350 fairly well, even if the input voltage is only 18 volts or so.
brockster	Car Battery Charger	Monday, December 07, 2009 11:04:58 PM
Thanks for posting this useful circuit! @Randy: Yes, you can substitute 510 ohms for the 500 ohm resistor. Better yet, just use a diode, such as a 1N4006. The cathode side should point toward the "in" terminal in the schematic. @zizo: Yes, you can substitute any similar "small signal" type diode as long as it can handle 200 ma of current and 70 volts of repetitive reverse voltage. The popular 1N4148 ought to work. @anonymous: Use the momentary switch as indicated. This is just a "force to start the charge cycle" button. The cricuit may start charging even without pressing this button. You can find momentary switches at Radio Shack or any electronics parts shop. @Woody: The maximum charge rate is limited to 2 amps. This is set internally by the LM350 voltage regulator. @Martins and Umar: To get more output current you would need to add a "current pass" transistor to the circuit or use several LM350's in parallel. You would be better off not using this circuit and simply using another circuit rated at 10A. See the application circuits in the LM350 datasheet (link below) for ideas. @All: This circuit is from the LM350 datasheet. See this circuit, and other charger ideas, in the datasheet at http://cache.national.com/ds/LM/LM350.pdf
Tim	Car Battery Charger	Sunday, December 06, 2009 4:41:52 PM
I'm a mechanical engineering student working on a senior design project. All the electrical stuff is a little out of my element. I'm needing a circuit to charge a 12v car battery from a DC generator. Would this circuit be what i'm looking for?
Randy	Car Battery Charger	Friday, November 06, 2009 6:20:15 PM
can you Substitute R1 500ohm with a 510? and R5 230 with a 220 i am unable to find them. thank you
anonymous	Car Battery Charger	Saturday, September 12, 2009 9:54:40 AM
can i replace this switch with a non momentary switch
zizo	Car Battery Charger	Thursday, September 03, 2009 8:42:33 AM
I could'nt find D1 1N457 Diode. What can use else instead of it ??? is there any substitution ?? thank you.
woody	Car Battery Charger	Thursday, July 16, 2009 9:09:10 PM
I like your circuit but the info does not state the maximum current charge rate. please state same. thanks.
umar	Car Battery Charger	Saturday, July 11, 2009 3:12:11 AM
Thank's for your circuit. I need a battery charger that can charge 12 V 10 A. what can I do for that problem, can You send me circuit for that? Thank's....
anonymous	Car Battery Charger	Saturday, July 04, 2009 12:40:53 AM
Yes you can charge a 12v battery using another 12V battery. But connecting the two batteries directly will not charge the empty battery since the voltage difference is zero. You will need a DC to DC converter to convert 12vdc to a higer voltage level commoly 13.8vdc. You cannot expect that the empty battery will be fully charged before the the other battery is drained. You cannot transfer all the charge from the 1st battery to the 2nd since the DC to DC converter will dissipate some power (resistors, transistors, transformer....).
Arthur	Car Battery Charger	Wednesday, July 01, 2009 4:07:39 PM
I wanted to know if I can connect my car battery to the car battery charger while it is plugged up?
Sokvan In	24V-Car Battery Charger	Friday, June 26, 2009 6:36:06 AM
hello, i'm a student and i wanna ask you a question. i wanna make 24V-car battery charger. but i'm not sure how to make it. could you give me some advice, thanks beforehand.
Rob	Car Battery Charger	Wednesday, June 10, 2009 6:19:32 PM
I already built the circuit but when I first connected the battery the led turned off, but when a few minutes later I disconnected it and connected again and the light didn't turn off again...could you help me!!!
MARTINS	Car Battery Charger	Wednesday, May 27, 2009 1:59:06 AM
HOW CAN I IMPROVE THE OUTPUT CURRENT OF THE LM350 REGULATOR?
martins	Car Battery Charger	Wednesday, May 27, 2009 1:46:03 AM
how does lm301a 0p amp operates in the circuit diagram above?
TARIQ	Car Battery Charger	Monday, May 04, 2009 10:43:37 AM
Thanks for your circuit, It is very simple and easy to built, Can i charge a car battery 12V40Ah ?
Eric K	Battery charger/maintainer	Sunday, April 05, 2009 7:05:42 AM
I just bought a battery maintainer for $20 at a local shop and have seen similar items elsewhere for similar money. Google for "battery maintainer". I see Home Depot has a Black and Decker one listed for about that. Cheaper and a little less bulky than a full on battery charger.
OSCAR	Car Battery Charger	Saturday, April 04, 2009 6:42:14 PM
Thank you for the circuit
anonymous	Car Battery Charger	Thursday, March 19, 2009 12:40:56 PM
I need a battery charger that will allow me to charge up my battery, while drawing from it 12volts @ 6 amps intermittent. What unit do you recommend that will not allow ac to come into my two way radio? In other words, I want my battery to be topped off, while keeping the charger hooked up to it. Is this possible? Your suggestions/comments, etc. Thanks, Chuck
anonymous	Car Battery Charger	Wednesday, March 18, 2009 6:03:51 PM
Just make sure the transformer or the input voltage gives at least 5A or else you won't get 5A out of the LM338. However, I am wondering if I can use a general comparator (LM339) instead of the LM301, it seems to work better when simulated in Multisim. -Nick
George	Charge a device of 23V battery from a 24V car battery	Thursday, March 05, 2009 6:45:13 AM
I was wondering if I can charge a 24V lead acid battery from another 24V lead acid battery. Can I remove the charge from one battery and transfer it to the other? If yes, which electrical device could do this? Thank you
Dark	Car Battery Charger	Monday, February 16, 2009 12:01:59 PM
Can I replace the LM350 with an LM338T? To get 5A current
alberto	Car Battery Charger	Thursday, January 29, 2009 11:16:57 AM
Hello, I have to charge a lead/acid battery 6V 140Ah (!!), will this circuit functioning? Which part should be modified? Thank you
oscar	Car Battery Charger	Friday, January 09, 2009 5:16:31 PM
good diagram.
ray fok	Car Battery Charger	Wednesday, December 24, 2008 11:53:48 AM
I have a 20-year old car battery charger (12 volts) still in good condition. My question is : can I still use it to charge a late model car battery ?
Chuar	Car Battery Charger	Wednesday, December 17, 2008 11:19:23 AM
Sorry for disturbing, if i'm using solar panel(17-20V,3Amax), replace the 18Vin in ur schematic diagram, and charging the distilled water car battery(12V33Ah), will this circuit functioning? or which part should be modified?
mark leow	Slow Car Battery Charger	Saturday, November 29, 2008 5:10:42 AM
I need a car batteries charger when I'm away say .... about one month. All I need is to connect to my garage electricity supply and the other end to my car battery. This 'Slow" charge will able to maintain the battery power , hence to preserve the electronics memory. Is there such a charger available in the market now?
gee	Car Battery Charger	Tuesday, October 28, 2008 2:51:15 AM
In the schematic of the circuit says it needs 18 v input and the output of the transformer of the power supply circuit is just 15v. That means output of the power supply circuit is less than the input of the charger circuit (18v). Is that ok ?
OZAN SEVİNÇ	Car Battery Charger	Saturday, October 18, 2008 4:57:39 AM
hi anonymous. in this circuit, I could'nt find D1 1N457 Diode. What can use the another one?
anonymous	Car Battery Charger	Thursday, September 25, 2008 10:12:07 AM
what is the maximum input current that can be handled by the LM350 regulator? also, my input voltage fluctuates between 9v and 20v (pedal DC generator) and I would like to add a smoothing capacitor, what size cap do you recommend?
anonymous	Car Battery Charger	Tuesday, September 16, 2008 3:01:22 AM
does anyone know what the circuit in the above schematic outputs? is there any modification required inorder to get 2A and 15v at the output?
anonymous	Car Battery Charger	Tuesday, August 12, 2008 11:56:44 PM
what is the output voltage in the circuit
laura	Car Battery Charger	Saturday, August 09, 2008 9:52:34 PM
this am i charged my boat battery. then tried to start the boat it wouldnt start. so went to make sure battery had full charge, since i ran it down trying to start it. well now the light on my battery charger is lit when i firsyt plug it in. i havent even attached the black and red leads to the battery. but when i do attach them both the green charge lite goes out. but if i disconnect 1 of the leads the light comes back on. it didnt do that earlier this am when i first charged the battery. i know its in the charger. but how do i fix it? is a fuse blown in the charger/ pleas ehelp if ya can thanks L
Rockets	Car Battery Charger	Tuesday, August 05, 2008 3:56:35 AM
Hello, can you explain how the circuit works? and what is the circuit supply? is it AC or DC?
anonymous	Car Battery Charger	Friday, August 01, 2008 4:29:08 PM
Can this circuit be used to charge small SLA type batteries(4.5AH)for example?...Id hate to have one explode in my face..it would really ruin my day;)
blaise	Car Battery Charger	Friday, August 01, 2008 9:30:35 AM
is s1, of the charger section, a momentary switch ? or fully latched.
RODNEY LAMAY	Car Battery Charger	Thursday, July 31, 2008 9:11:46 PM
Sir I have a 18 volt output solar cell All markings are off,I checked the output with my Multi Meter.What ma or watts will it put out please with your curcuit as shown. Does it turn itself on and off ? why does it need a switch ? Will it work without one ? Thank You Rodney LaMay
anonymous	Car Battery Charger	Thursday, July 31, 2008 5:45:09 PM
Can i charge 12V battery with 24v charger?
anwendyburton@onwywendymous	Car Battery Charger	Saturday, July 05, 2008 4:35:17 PM
hi please can you advice I have a 6 amp charger,I have put a lesiure battry on, so I can use in my caravan, the light was green when I put the charger on today the full charge light is red. Does this mean the battery is fully charged or dead .
anonymous	Car Battery Charger	Sunday, June 22, 2008 8:57:33 PM
Looked at the comments, many seem new or are confused. This charger will charge at 3 Amps Max. (with heatsink on Regulator) The circuit works by monitoring the current through the voltage drop through the series output R7 (the more current, the lower the voltage). The op-amp (as a comparator) compares the output with the reference voltage provided by the R4/R5 Voltage divider. When "on", the output of the op-amp is high, no current flows through Q1 or R6. When the charging current drops (batteries draw less current from charger the closer they are to 'full'), the voltage drop across R7 decreases, increasing the voltage at the inverting input of the op amp. When that voltage is higher than the reference from the R4/R5 voltage divider, the ouput of the op-amp goes low, putting R6 in parallel with R2, and turning on Q1 which turns on the LED. R6 in parallel with R2 lowers the voltage on the adjust pin of the regulator, effectively turning it off. The circuit allows a 30mA trickle charge through R1, which also provides power to the circuit. My opnion is that a 3 Amp charger IS a trickle charger, There are lots of other circuits around that use several paralell MOSFETs to get high/normal charge rates. 2 amps on a half-dead battery would take over a day to charge. However, the low current method is the only way to salvage a fully discharged lead acid battery, if at all. Hope that answers everybody's questions. (no, I didn't create this circuit, just came across it and thought I'd comment)
Mike	Car Battery Charger	Monday, June 16, 2008 11:50:21 AM
Ok Azam, Trickle type chargers apply low current to batteries, there is some debate over whether or not this is harmful but most decent chargers shut off when the battery is full. If you are simply going by the packaging you want a charger labeled as "intelligent." It contains a microprocessor that monitors the state of charge and when it is done charging, checks the voltage every hour or so just to see if the battery is still fully charged. What you definitely do not want is an old-fashioned 'trickle-only' charger, I don't even think anyone sells them anymore, they are just a power supply and a diode, nothing else.
henry	Car Battery Charger	Friday, June 13, 2008 9:10:16 PM
what is the substitute for the IC LM 301,can LM 317 be use instead of the LM 350
Georges	Car Battery Charger	Friday, June 06, 2008 3:49:48 AM
First when i connect the circuit to power or to the batterie the led turned on . Second if the circuit is connected to power and i connect the batterie the lm301 suddenly corrupted. third the open switch when pushed the led turn off. the batterie used is lead acid batterie 12 volt 7A the power supply 20 volt DC created from a transformer 24v 3A with a bridge 5A. Please waiting your feedback.
faisal billah	Car Battery Charger	Sunday, June 01, 2008 11:55:17 AM
wonderfull idea,very usefull
Azam	Car Battery Charger	Friday, May 30, 2008 6:49:08 AM
Can someone compare and explain why battery chargers in the market have trickle charging system that takes twice the time to charge a car battery.How can I tell if a charger is trickle type. I need fast charging that I believe is available only in Full wave bridge charger.Please educate me
Mike S	Car Battery Charger - what's the switch for?	Saturday, May 10, 2008 7:01:53 AM
Hi, I was wondering if anyone's built this ct. and had it working 100% correctly - following the schematic exactly. Also, what's the switch for? It looks like it temporarily stops charging but I'm not sure about that. And why doesn't the author reply to any of the questions that have been asked here? Thanks, Mike
anonymous	Car Battery Charger	Monday, May 05, 2008 8:16:54 PM
can anybody please explain how the circuit works? i'm a beginner in electronics
naleli macclay	Ni-Cd checker	Friday, April 25, 2008 8:36:53 AM
its my first time, to visit this site so i guess am impressed.
anonymous	Car Battery Charger	Monday, April 21, 2008 12:45:37 PM
This circuit is "old" and right out of National Semiconductors LM138 "Typical Applications". It works well... ~20 years ago I built a 40A version... and it's still running today.
Tom	Car Battery Charger	Friday, April 18, 2008 12:04:35 PM
Hey, I am looking to build a battery charger, but my application is for a battery powered welder. So I will be pulling approximately 100 amps off of the batteries. Will it hurt this charger to be connected when drawing 100 amps off the batteries? If so, is there a clever way to make the battery charger disconnect when the battery amperage is high? Thanks
Ilya	Car Battery Charger	Tuesday, April 15, 2008 3:26:31 PM
What changes should be made to the circuit in order to use it for a 12V battery. Also, the battery I am planning to use is a higher current battery than an average car battery. Should I consider making any changes to the circuit? Thank you.
anonymous	Car Battery Charger	Friday, April 04, 2008 7:01:58 PM
jotham - "quote from the author" "When the battery is fully charged, the circuit switches off and lights a LED, telling you that the cycle has finished." vicky - id check the transistor Q1, it has to be PNP and properly connected so the led works properly, also check the ouput of the OP amp, it should be connected to the base of Q1, maybe thats it... Anonymous (Feb 19) - well duh , go to walmart or something, this site isnt meant for that Anonymous (Feb 8) - (N1/N2) = (V1/V2) so the turn ratio should be directly proportional to the given voltages, but considering current calculations (wich i dont have at hand now) getting the laminated nucleus, etc... you are better off buying one than making one, they are usually sold in voltage and current rating, like " a 120 VAC to XXVAC XAmps transformer" Anonymous Feb01 - it is most likely to work, i mean... voltage isnt much of an issue as long as its higher than 14 volts or so, however as you can see in the power supply he suggests a 5A bridge rectifier, if the circuit draws that much current and your solar panel doesnt handle at least that much current things might not work out, id like to know the maximum current the circuit draws
Olebak	Car Battery Charger	Friday, April 04, 2008 4:50:02 PM
I'm a bit confused about this charger . 1 the LED is always on when power is applied to the circuit, 2 how does this comparator operate and what is it comparing. could you please elaborate a bit more on how the circuit operates please. Any one who can help please do.
Chris Dreyer	Car Battery Charger	Sunday, March 23, 2008 5:19:17 AM
HI, THANK YOU FOR A VERY USEFUL ARTICAL. SOMEWHAT A NOVICE WITH CERTAIN ASPECTS OF ELECTRONICS AND CHARGERS, I NEED TO ASKED A QUESTION OR TWO. IN SOUTH AFRICA WE EXPERINCE A LOT OF POWER FAILURES AND HAVE TO FIND ALTERNATIVES TO ATTEND TO THE ESSENTIALS, LIKE MY MOTHER BEEN ON OXGESION. 1. CAN THIS CHARGER CHARGES TWO BATTERIES SIMILTANEOUSLY? (TWO 12 V BATERIES IN PARALLEL) 2. WHAT ARE THE MAXIUM O/P CURRENT THE CHARGER GIVEN THE FACT I WANT TO CHARGE TWO BATTERIES SIMILTAIONSLY. YOUR FEEDBACK WILL BE APPRECIATED. REGARDS CHRIS
santhosh	Car Battery Charger	Wednesday, March 12, 2008 10:17:03 AM
I have a battery but i don't know the Ah of the battery.It is a motorcycle battery.can i charge it with this circuit.What will be cost of this project?
princy	Car Battery Charger	Saturday, March 01, 2008 12:55:31 AM
Is there any possibility to make the car battery charger work whit using heatsink?
jotham	automatic Car Battery Charger	Friday, February 29, 2008 3:59:10 AM
hi .if the battery is full of charge what is the reaction of this charger.?
vicky	Battery Charger	Thursday, February 21, 2008 3:24:47 AM
I've tried wiring the circuit but the LED is permanently on, what can be the problem? Also how does it regulate such that when the battery is full, it won't overcharge? Also the connection for lm301 is not clear, where is pin 5 connected and pin4 is not clear. Can is use lm741 if i don't have lm301?
anonymous	Car Battery Charger	Tuesday, February 19, 2008 6:01:05 PM
This site helped me none on finding out what type of car battery charger I should purchace.
ugo	Car Battery Charger	Tuesday, February 12, 2008 8:14:59 AM
can u send me a circuit diagram of a 12V automatic battery charger (Editor's notes: Just look at the "Related Circuits" section of this page.)
anonymous	Car Battery Charger	Friday, February 08, 2008 6:59:13 AM
how do one calculate turns ratio given only primary and secondary voltage
anonymous	Car Battery Charger	Friday, February 01, 2008 5:03:29 PM
If i would use a lower voltage than 18v, would this stop working then. I'm only asking this because i would like to connect this to my solar panel which is able to deliver me 17.2 V. I'm willing to use this in my RC solar powered car
anonymous	Car Battery Charger	Friday, December 14, 2007 2:47:15 AM
i just would like to say, that the opamp is a comparator in this case inorder to tell that the battery is full and the PNP is used inorder to invert the output of the opamp, NPN can be used preceded by inverter but it will be pointless. I designed a charger using burt tech. but i'm not pretty sure about it. it uses a Pic processor.if some1 interesting send me a mail.
?????	Car Battery Charger	Thursday, December 13, 2007 2:22:44 PM
omg this wesite is really help full!!!!!
marki	Car Battery Charger	Wednesday, December 12, 2007 11:52:07 AM
HI MISTER. WITH THIS CHARGER I LIKE TO CHARGE 160Ah BATTERY. ITS POSSIBLE OR NOT .PLEASE TELL ME THANK YOU IN ADVANCE
anonymous	Car Battery Charger	Sunday, December 09, 2007 8:26:58 PM
I need to charge a 125 VDC battery bank, do you have any schematics of a battery bank charger what help us in our project?
Saad	Car Battery Charger	Monday, December 03, 2007 1:16:54 PM
HI. ME DOING ELECT. ENGR. HOW MUCH TIME REQUIRED TO CHARGE 65 APMARE BATTERY TO FULLY CHARGED????
anonymous	Car Battery Charger	Wednesday, November 28, 2007 1:47:45 PM
I have a 24V transformer, would it hurt anything if I use it in this circuit.
ertur	Car Battery Charger	Friday, November 16, 2007 10:57:52 AM
Hi I am a final year mech engineering student doing my final year project which involves the building of a wind turbine. I need to charge up batteries from a dc generator by means of a trickle charger and voltage regulator. Do you have any schematics that i could use to perform this operation Your help would be greatly appreciated ertur
ertur	Car Battery Charger	Friday, November 16, 2007 10:53:03 AM
can you analyse the Car Battery Charger circuit by details please :)
hussain al lawati	Car Battery Charger	Sunday, November 11, 2007 1:09:35 AM
What is the purpose of using a pnp BJT and the OP-Amp? Can we use an NPN transistor? Why or why not?
Sherihan	Car Battery Charger	Saturday, November 10, 2007 6:06:03 AM
can you analyse the Car Battery Charger circuit by details ?
Ranjan	Car Battery Charger	Friday, November 09, 2007 4:06:59 AM
How can I make this circuit to charge 24 volts battery?
anonymous	Car Battery Charger	Thursday, November 08, 2007 9:41:06 AM
where is the point for the power supple of this circuit above
anonymous	Car Battery Charger	Friday, November 02, 2007 3:13:16 AM
Could you explain to us the slow charge and fast charge charger in a sealed lead acid battery? Thanks!!!
Uberfly	Car Battery Charger	Thursday, November 01, 2007 2:30:59 PM
Fantastic! I've been looking for a simple working circuit like this! Thanks a lot...
Jimmy	Car Battery Charger	Wednesday, October 31, 2007 10:47:56 AM
The diode in series with R3 is LED.
Jimmy	Car Battery Charger	Wednesday, October 31, 2007 10:30:18 AM
What is the description of the "diode" in series with R3.
Andrew	Car Battery Charger	Saturday, October 27, 2007 10:37:10 AM
pls how would i upgrade this battery charger to deliver 15amps
anonymous EMMANUEL SEGUN ALABI	Battery Charger	Friday, October 19, 2007 6:56:35 AM
sir,i am a student of mechanical engineering at university of Ilorin,Nigeria.if a battery charger got burnt in the process of using it by producing smokes,what are the likely causes and solution to this problem. I wish to design battery charger and electrical inverter,kindly suply me with the descriptions and circuit diagrams on how to go about it.Thanks in anticipation.
vaibhav vijay rane	solar-wind charger.	Tuesday, October 16, 2007 4:53:01 AM
sir, We the students of final year Mechanical engineering are making a charger which will consume both solar & wind, the two non-conventional energies at the same time through a generator, via.I.C(integrated circuit) to a storage battrey from which it can be used whenever needed.This charger can be used to charge many electronics equipments(example: lap top, mobiles,i-pods,etc) so we request u to please give us as many information that u have with u. waiting for u'r reply........... thanking you in anticipation
Tori	Car Battery Charger	Sunday, October 07, 2007 10:01:09 AM
Would you be able to supply me with a brief description of how this circuit works?
anonymous	Car Battery Charger	Friday, September 21, 2007 9:49:17 PM
Is it possible to charge a 9V Battery with a battery charger with alligator clips???
chigozie	Car Battery Charger	Monday, September 17, 2007 7:25:27 AM
pls after building this circuit can it work ? besides, i would like to be visiting this site regularly what can i do?
Novi	Car Battery Charger	Monday, September 17, 2007 4:45:15 AM
hi, I try to buy 0.2 Ohm 10 W Resistor & 1N457 Diode, could U give me another alternative for these two component ? thank's a lot
anup	Battery Charger	Thursday, September 13, 2007 2:48:03 AM
i wanted to know about a circuit for a battery charger where even if the input voltage keeps varying, it should not affect the battery charging procedure. i wished to install such an arrangement in vehicles where the speed keeps varying & i do not want the voltage input to affect output voltage. thank you.
kisskisng	Car Battery Charger	Wednesday, September 05, 2007 11:16:47 AM
hi i want ask you about your Car Battery Charger if the battery is empty can i use it or not plz i need your answer
yogesh	Car Battery Charger	Monday, August 27, 2007 11:06:41 AM
hey i m also doing a similar sort of project on battery charging using wind energy any ideas how to go about wind turbine
anonymous	Car Battery Charger	Friday, August 24, 2007 9:26:10 AM
pls, i'm in need of the car battry charger cct analysis. God bless you for responding positively. Thanks, Egbirika J.N.
rainer	Car Battery Charger	Friday, August 17, 2007 5:43:56 AM
i need to charge a 120 volt dc battery bank with 10 amp can any one help rainer
Odel	Car Battery Charger	Friday, August 17, 2007 4:05:13 AM
Can I ask you a favor to provide me a manual charger using my bicycle. I am in a remote area using a battery for my flourecent lamp. I used to bring back my battery to nearby town for charging. I will greatly appreciate if you can help me with my problem. Thank you very much in advance.
anonymous	Car Battery Charger	Tuesday, August 07, 2007 2:04:28 AM
this circuit is a copy from national semiconductors LM 338 voltage regulator Ic data sheet. better we search LM338+pdf in google.
NALEN	Car Battery Charger	Monday, August 06, 2007 10:37:49 AM
Hi Im a currently a final year mechanical engineering student doing my final year project which involves the building of a wind turbine. I need to charge up batteries from a dc generator by means of a trickle charger and voltage regulator. Do you have any schematics that i could use to perform this operation Your help would be greatly appreciated Nalen
rahman ajani	Car Battery Charger	Thursday, August 02, 2007 1:09:08 PM
pls, i need to know if i can get a circuit on automatic 12v battery charger.using 2 ics and 2 transistor.pls i need ur help its my school project
wilham	Battery Charger for microhydro	Friday, July 27, 2007 1:25:04 AM
hi, i'm from indonesia, i need u,r help to make a battery charger with constant voltage but in different current and this battery connected to inverter and synchronized to system microhydro... thanks a lot
Collins	Car Battery Charger	Tuesday, July 24, 2007 8:21:16 AM
Please, How can I use this Charger on a 120A Dry Cell Battery? Need full schematic diagram and modifications.
James	Car Battery Charger	Sunday, July 22, 2007 3:52:31 AM
Brilliant. one press and away it goes. everyone is asking stupid questions...... Why would you want to use it to run an inverter (12v to 120v) If you were using this charger off 120v you wont need to. and if you were using a battery to charge a battery (Dumb) you would just connect the inverter to the battery---FORGET THE CHARGER
saheed	My question is	Friday, July 20, 2007 11:08:13 PM
The Ampere-Hour-Rating of the battery charger, and also how to calculate the rating of the power.Its a nice project and i will like to used it as my own project.Can u pls send me the solution to my question.
Waleed	Car Battery Charger	Tuesday, July 17, 2007 4:09:52 AM
hey ; can i use this circuit to charge 6 V motorcycle battery ? and thanks for help :)
Mohamed	there is a question	Saturday, July 14, 2007 8:06:43 AM
can i use this circuit to charge a 6v battery used in motorcycles? and thanks for your help please if my question has any answer, send this answer for me
andrey	Car Battery Charger	Saturday, July 14, 2007 4:18:55 AM
can this circuit to charge the AA NiCd/NiMh,and how to make this circuit has a display to know if the battery has been full..please give me answer (Editor's notes: No.)
Qazi Muhammad Imran	Car Battery Charger	Friday, July 13, 2007 8:36:25 PM
This circuit isvery halpfull...
john raul cormina	Car Battery Charger	Wednesday, July 11, 2007 7:48:51 PM
is this circuit can charge a 12 flets car battery?
anonymous	Car Battery Charger	Tuesday, July 10, 2007 12:46:14 AM
how should a pair of underage naive teenagers go about charging a car battery with no experience without a second car BUT we do on the other hand, have access to a car battery charger?
bright	Car Battery Charger	Saturday, July 07, 2007 4:12:20 PM
please can i use this charger for 12V TO 120V INVERTER,i will not use it in a car
anonymous	Car Battery Charger	Tuesday, July 03, 2007 10:47:19 PM
How can it be upgraded to be able to charge a 200AH battery?
adewale raji	Car Battery Charger	Wednesday, June 27, 2007 8:21:45 AM
can l get one for 62Ah
Benny	Car Battery Charger	Sunday, June 24, 2007 6:27:28 AM
Is the power supply needed 18 V and no less? Could AC/DC adaptors also be used as power supply? Can you provide substitute parts description as alternative in case we don't those listed in our country, Philippines? Is there a way to detect the actual charge in volts? Is there a time limit for this to charge?
anonymous	Car Battery Charger	Friday, June 22, 2007 7:15:32 PM
can i use 1A transformer (15v)
mohamed	Car Battery Charger	Monday, June 18, 2007 7:34:09 AM
can i use solar panel as a power supply
anonymous	Car Battery Charger	Friday, June 15, 2007 10:07:17 AM
Nice work, its a good circuit, this charger is good when the battery of the car is uncharged.
jafoy	Car Battery Charger	Friday, June 15, 2007 2:58:13 AM
kindly,give some substitutions in 1n 457 diode.because the availability of this product is scarce in ph. also include the pcb layout in this project. i have replaced 1n 457 with 1n 754(6v) but the charger is subjected to glitch!!!!! a need ur immediate response... thank u....
Tommy	Car Battery Charger	Thursday, June 14, 2007 8:17:43 AM
May you provide this battery charger for 255 amps? Thank you very much
thandoswaziland@yahoo.com	Car Battery Charger	Wednesday, June 13, 2007 7:54:57 AM
can some please explain what is go on because it is ideal as a project
thando	Car Battery Charger	Wednesday, June 13, 2007 7:22:56 AM
how does this circuit work, as in step by step analysis, from the heatsink down to the battery terminals
anonymous	Car Battery Charger	Tuesday, June 12, 2007 6:04:02 PM
That is a simple circuit, and should work on most batteries of 100 Amp hour or less. Could use the Op Amp to drive a opto scr driver circuit for more amperage. Would need a larger transformer though and scr's.
Roy Laybutt	Car Battery Charger	Friday, June 08, 2007 8:06:01 AM
Can you provide this battery charger for 120 amps please Roy
anthony akabueze	Car Battery Charger	Wednesday, June 06, 2007 8:57:28 PM
it's wonderful.keep it up!
ack Hunter	Car Battery Charger 2/4/6 amp car battery charger	Wednesday, June 06, 2007 1:36:40 PM
What does the 2/4.6 amp mean?
Philip E Lori	12 volts Car Battery Charger	Friday, June 01, 2007 6:38:21 AM
I want to know the principle of operation i.e how it works, the minimumand maximum amount of current required. I also need the design calculation of the circuit.Please i need it as fast as possible.
SEYI	Car Battery Charger	Thursday, May 31, 2007 5:36:29 AM
i want somebody that can put me thru cos i'm using it for my project
Terry	Car Battery Charger	Tuesday, May 29, 2007 2:15:12 AM
Hi, Does anyone have a PCB layout for the battery charger? It would be much appreciated! Cheers
anonymous	Car Battery Charger	Monday, May 21, 2007 2:52:27 PM
the circuit could be very usefull if i could connect it with a small dc generator (from wind power), but 18V on the board suplly is dc or ac?
anonymous	Car Battery Charger	Friday, May 18, 2007 8:34:06 PM
Tested it using a TLO81 instead of LM301A, work perfecly.
gm_karutz	Car Battery Charger	Sunday, May 06, 2007 8:00:00 AM
Is this can be use in dry cell battery?......can i use larger amperage for this project?
R.V.Raghav	Car Battery Charger	Thursday, May 03, 2007 12:46:44 PM
can it be used to charge a 12V UPS storage battery of 1.5A(approx.) otr a motor cycle batt. of 12VDC and what if i connect it to a solar cell of 17.8 (0.4x4x11 = 17.6VDC?)
anonymous	Car Battery Charger	Thursday, April 26, 2007 12:16:24 PM
I am looking for a transfomer with a rectifier (Charger) which deliver a continuous load to a 12-volt Motor with a permanent magnet continuous runing. There is such a thing? Thanks J.U.
louis	Car Battery Charger	Monday, April 23, 2007 1:58:36 PM
How do i change this clever circuit from 12v to 36v charger .thank you ....
ramy	Car Battery Charger	Sunday, April 22, 2007 12:23:40 PM
Hi Could we use this charger for dry dattery? THank you
Dina	Car Battery Charger	Wednesday, April 18, 2007 1:01:59 PM
This circuit is very useful ,I want it in my graduation project but I want more details about the operation of this circuit,as for first more information about regulator U1 also information about the input of the circuit ,please answer me in fast time,thanks.
janb maicheal alga	Car Battery Charger	Wednesday, April 04, 2007 12:56:50 PM
could i connect two or more batteries connected in parallel?or if not, ill use a 15A transformer in order to make current enough for the batteries. could you send me how this circuit work?that wen i press the S1 the op amp will balance an compensate the voltage supply to the battery, how it detects the current of the battery and how it switches off the systym.I just wonder how it switches off b'coz i examine the connection its just a parallel connection and directly connected to battery....hope for your response.
Clint Wood	Car Battery Charger	Friday, March 30, 2007 2:02:18 PM
Will this work for a solar panel as the power supply and is it safe for a deep cycle battery. e.g. sailboat battery
alex	Car Battery Charger	Friday, March 30, 2007 11:09:26 AM
the LED in instantly on, and when i press the start button it shuts off,while it is pressed. Any ideas why
scotty243	Car Battery Charger	Monday, March 26, 2007 12:07:47 PM
Pins 1 and 6 are NOT shorted together, and pin 5 is not connected to anything.
Catharine McCasland	Car Battery Charger	Monday, March 26, 2007 2:58:56 AM
Will this item charge a toyota 4 wd 6 cyclinder sux
ruko	Car Battery Charger	Saturday, March 24, 2007 9:10:39 PM
Have you posted the answers to the above questions somewhere? (Editor's notes: As it noted before the comments section, technical questions in comments are generally NOT answered by the webmaster. Your best bet is to search the forum.)
Ben	Car Battery Charger	Tuesday, March 20, 2007 4:06:51 PM
The connections for U2 are not completely clear. Are pins 1 and 6 shorted? What is pin 5 connected to?
J Stanley	Car Battery Charger	Monday, March 19, 2007 4:51:03 AM
Can this be used to charge a 6volt motorcycle battery and wich components will to change
anonymous	Car Battery Charger	Monday, March 19, 2007 1:43:50 AM
please include foil layouts and pcv
Rampa	Car Battery Charger	Saturday, March 17, 2007 8:05:18 PM
Hi guys. im from Argentine... and i got a question. Why only i got 4v 3.3A in the output???? that is normal?? anyway later i go try charging a baterry. bye bye. and sorry my english sux.
anonymous	Car Battery Charger	Friday, March 16, 2007 5:00:35 PM
When connecting the charger to the battery, do you connect positive to positive or positive to negative? (Editor's notes: What do you think? + to +, - to -)
kva	Car Battery Charger	Thursday, March 15, 2007 4:08:39 AM
Can i install it on car with the input replaced by curren generator ?
anonDave Morrisymous	Car Battery Charger	Saturday, March 10, 2007 8:16:29 AM
I have just completed the build and test of this circuit (which I have seen in a 1979 National Semiconductor handbook by the way!) and the charged voltage and current rates seem to work. The LED remains permanently illuminated, however.
Kalesh	Car Battery Charger	Wednesday, March 07, 2007 11:36:12 AM
what is the rating of the regulator? is it normal three terminal device or special high wattage one?how can I adjust the cut off voltage of the charger when battery is fully charged?
funsho adigun and co	Car Battery Charger	Wednesday, February 28, 2007 11:41:48 AM
how will i be sure that this circuit will work effectively

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