Mains Operated LED Circuit
This is a modified version of the circuit Super bright LED Night Light published here. This circuit is submitted by Mr. Seetharaman and its full credit goes to him.
This is the circuit of a well tried and reliable 230 Volt AC mains operated 24 LEDs (super bright 50mA LEDs). While practically compare the brightness between this circuit and 11watts tube, the LED light is much better. The layout is made in such a way, you get uniform illumination. A photograph of the cicuit is also given in this post.
Custom Search
Hello Seetharaman, Thank you and I appreciate your reply. May I also know if I can use the same value of resistor (220K 1/4w) if I wanted to change the value of the capacitors to be used for LED’s more than 24 nos, say 50 LEDs? Thanks again
Hi Jeh You can try by connecting 2.2uF 600 volt capacitors in series back to back (+ve of both capacitors connected together and both capacitors negative terminals used in the circuit make it 1.1uF non polar)with 220K 1/4 watts resistances connected in parallel with each one of them.
Hi Nagaraj you can submit your comment on the leave a reply coloun with your name and email address which will not be published. you can send your well tried circuits with the prototype’s photgraphs and a detailed write up to Mr. John of circuitstoday through his email id john@circuitstoday.com
Hi Arun Kumar you can use the same above circuit with 60 LEDs of 20mA by repacing 1uF 400volt with 0.68uF (can be 2nos 0.33 in parallel or one 0.47 and 0.22uF in parallel)400volts and 10uF160volts with 10uF 400volts. For 120LEDs use 2 sets of 60LEDs in parallel by using 1uf and 0.33uF in parallel in place of 1uF400volts in the above circuit, no other change is required.
Dear Mr Seetharaman,
I am an amateur and would like to replace all incandescent bulbs in my home with suitable LED lights.I plan to use 60 and 120pcs of LED’s used in 60 pcs in series and also in 60 x2 configuration (60 in series string and two parallel strings)Each led has Vf 3.2V, If 20mA ,reverse voltage 5V.Can you pls suggest a reliable circuit with values for the resistors and capacitors to be used .
how to comment and upload circuits?
Hello Seetharaman, I have been scouting for 1uF/400v capacitor here in my country but it seems that the only maximum available value we have is 0.1uF. Most capacitor with voltage capacity of up to 600v are electrolytic type capacitor. Could you advice me if it is possible for me to use such polarized capacitor and how to connect it. I am really exicited to assemble this project.
Thank you
Dear Sir
I tried the 24 LED circuit, it is very good and useful in small rooms. So many circuits i examined. I need good brightness to use in my house to avoid CFL. I used 8mm white LEDs. So I request you to send such a circuit and help me. Thank you. Udayan
Hi Yadi it cannot be predicted. you please feel the LEDs for temperature after a glow of minimum 3hrs. if they are warm better to reduce the current else their life will be reduced drastically. if they are cool running it is safe you can use it with 1uF itself.
hi sir,
thank you for your answer. 0,33uF cannot find in local market. i am already assembled 40nos dip 5mm strawhat led using 1uF 400V polyester capasitor, and the led glow very bright. i has been tried in 3 days, and the led is just fine. how long the time the led can be glow using dip 5mm strawhat with 1uF capasitor?
Hi Yadi the maximum value is 20mA at 3 to 3.2 volts.If you use them in the above circuit you have to reduce 1uF 400 volt to 0.33uF 400volt polyester capacitor. no other change is required.
if i want 2 increase the number of led what changes should i bring
hi sir,
what is maximum forward current value for dip 5mm strawhat superbright? because i use this for above circuit, but the led is not broken.
hi sir, very nice circuit,but cap current capacity (100 ma peak ) is greater than and led max currentas u said 50 ma peak ). then how can leds withstand such a huge current.
Hi Rasitha,
Wattage consumed by 24 LEDs @ 50 mA is 3.85 Watts. This is assuming that the voltage drop across each LED is 3v.
If drop across each LED is 3.2v, then wattage is 4.09 watts.
Send me your email address and I will mail you a calculator that I have made for finding Cx, Wattage and current flow thru LEDs.
How is the quality of the output Light. Is it bright enough to light a decent room. I am very much waiting to assemble this ckt.
What is the cost of 50mA LED in your local market?
Seetharaman sir, May the Year 2012 bring for you happiness, success and filled with Peace, Hope & togetherness of your Family & Friends…Wishing you a HAPPY NEW YEAR.
sir,
i assembled the circuit .. It is nice….what about the wattage of this and 50 LED circuit….
Hi Seetharaman,
What is the price of a High Bright White 3v 50mA LED in your local market?
Hi Seetharaman,
These High Bright White LEDs (3v @50mA) are they available in 2 pin or 4 pin or both type packaging.
If 4 pin packaging, how to wire them?
Hi Stanley you have to use both voltage and current peak value to calculate with filter capacitor, or both in RMS value. o.4 is not a standard value you can use 0.39uF which is around 2.5% less but will suit as the current change will hardly be noticed.
Hi seetharaman
What are those resistors for ? Are the series resistors used for surge current protection ? What are the parallel resistors for ?
Hi Seetharaman,
Are 0.4Uf standard cap available?
What combination to achieve 0.4Uf?
Hi Seetharaman,
In fact in many calculations and in your responses to Japanjot, Murali and Rahul, below, you have used 230 volts rms to calculate voltage to be dropped.
Hi Seetharaman,
With regards to your response, I am confused. In all previous comments to Cx calculations, you have said to use rms value of dropping voltage. Now you have responded to me to use peak value. Pls clarify
Hi Seetharaman,
Are 0.4Uf standard cap available?
What combination to achieve 4Uf?
Hi Rasitha increase 1uF to 1.2uF no other change.
Hi Stanley it should be 0.4Uf for 15nos 25mA LEDs,
for 300LEDs of 3volt @ 50mA it should be 9uF. calculate for peak voltage and current as AC is converted to DC. above 108LEDs no capacitor required, better to prvide a 250volt VDR as protection against surges.
Sir,
If I use 100 LEDs of 3volts 50mA rating, then total voltage a/c LEDs will be 300v (100 x3). But my mains is only 230v @50Hz. So logically no Cx required because no voltage drop required. Is my logic ok. If Cx required then how to calculate in this case.
Hi Seetharaman, I have connected 15 LEDs (3volts 25mA) in series using above ckt. Now using formula, I have come to value of Cx as follows. Please let me know if my calculations are right. Also what is the standard nearby value of Cx available.
Total voltage a/c LEDs is 45v @ 25mA (3 x 15). So votage drop required is 185v @25mA (230-45). So R is 7.4k ohms (185/0.025). So Cx is 0.43mF. So what is standard nearby value of Cx
Secondly, If I use 21mA for LEDs Cx comes to 0.36mF. So can I use 0.33mF Cap?
sir,
…….how i can cnnct 50 LED s……to this circuit…what will be changed……?..
Hi Malli check after running for 15minutes whether LEDs are getting heated up. if not no problem. if they are getting heated up reduce the capacitor value to next available lower value. Driving the LEDs with higher current will reduce their life.
Hello sir here the available capacitor are .22 .33uf .47uf .68uf, I tried with .47uf for 24 led and .68uf for 48led its working fine and bright. can i use like this or i have to change. all leds are 3.2v 20ma. if i have to change what should i do pls help me sir
Hi Malli for 24LEDs of your specification reduce 1uF to 0.39uF, for 48 LEDs reduce 1uF to 0.57uF (0.47 + 0.1uF) for 72 LEDs use the above circuit no other modifications are required.
Hi Nishanth you cannot mix up LEDs. same type alone can be used in series. To use 50nos RED LEDs in series use the same circuit reduce 1uF to 0.33uF no other component requires any change.
hello sir,
please explain how to connect 50no’s of LED in AC mains
hello sir,
how can I use five bright LED’s forty five red LED’s in the circuit in series.What changes needed to make in the circuit
sorry sir its 3.2 3.4v 20ma led. not 25ma. please help me
sir i have 3.2-3.4v, 25ma led iam planing to do 3 types of led, 24nos, 48nos, 72nos please help me and let me know what are d changes i have to make in this circuit
malli
Thanks Seetharaman for the unselfish reply/information. May I again ask you a favor if you could publish a transformerless power supply circuit that is connected from the main (240v) and gives an output of 9v dc. This is to be used for IC operated projects like LED Chaser etc.
More power!
Jeh
Hi Jeh you can use 2 capacitors in series, ensure that you use 220k resistance in parallel with each capacitor. (capacitor voltage value will get doubled but capacitor value will get halved if you use them in series).
Hello Seetharaman, We dont have 400volts range. We only have 250volts. Though some electrical appliance use 2000volts. Can I use the 250volts capacity?
Thanks
Hi Jeh what is the maximum value available in your market in 400volts range. if 0.47uF(470nF) use two in parallel.
Hello Seetharaman, Thanks for the reply. I intend to assemble the project that I have bought all the parts except for the polyester capacitor (1mf/400v) which is not available locally. Could you advice me if what could I use as a substitute?
Thanks and more power
what about the bridge rectifier diode number(in4007 ah?)
Hi Hari in this circuit current and surge limiting are taken care by 100ohms before and the one after bridge rectifier plus the filter capacitor 10uF before LED circuit
Hi Jeh the above circuit is the correct one.
Hi Anish you are correct normal LEDs can handle but they get heated up soon . you kindly checkup the temperature raise of LEDs after about a minute of glowing (by using heat sensitive part of your body-may be back portion of palm or face) if it is quite warm, the LED current has to be reduced or you have to use thick large PCB to dissipate the temperature. if the raise in temperature in not taken care the LEDs will fail fast.
Hai seetharaman sir,
My attempt to find whether the LED’s I have are super bright or not:
I do not have a constant current source. So, i used a 5v regulator and 200 ohms resistors which gave around 24mA. Then the voltage drop was around 3.0 volts. When I replaced 200R with 100R, the current supplied was around 46mA and the voltage drop across LED is around 3.15V. How can I conclude? BTW, normal LED’s wont stand more than 25mA i think… Am i correct?
Hello Seetharaman, I was looking/surfing for a circuit for LED and found this site. I read the chain of messages and have read about the circuit diagram which is incorrect. You said that you have corrected on your comment dated 26 June 2010 of which I did not see. May I know if the diagram above is now the edited or corrected one?
Thanks and regards
Hi Seetharaman,
Thank you for the help. One more doubt. There are strong recommendations to use LEDs only with a current limiting resistance(since a small change in V can make greater change in I without a resister in series and harmful for LEDs.) I guess 100E used after bridge to limit surge also acts as a current limiting one. Or do we use one more suitable resistance for current limiting ?
I found some useful information regarding LEDs with FAQ and some wizards to calculate circuit config. at
http://led.linear1.org/led.wiz may be useful for many reading this post.
Hi Hari with 3.2 volt 25mA LEDs it will be 61 volt 25mA. you require only 0.39uF at the most you ca use 0.47uF. with 1uF it will draw >50mA which may damage your LEDs. If you wand Zener protection use 32volt 1watt zener Diodes in series and in reverse bias condition in parallel with 19uF 160 volts against surge (not really required)
Hi Seetharaman
Thanks for your advice. Now I have rewired 19 LEDs in Series, but total voltage is around 60V for 19LEDs(using 1Mf/400V). I guess it is drawing more current, since LEDs are VERY bright.
I invite your attention to your response to Mr. Murali dated October 5, 2010 as…
“Hi Murali for 19 LEDs reduce capacitor to 0.82uF, a standard value or use a 15volt in series with th LED loop.”
You didn’t mention the 15V component, I guess it is a zener reverse biased ? Please clarify.
I hope I can use a 0.33Mf and 0.47Mf in parallel instead of 0.82Mf if available. Here I get only 1MF and 0.47MF/400V capacitors in the local stores and no other value is currently available.
Hi Babla each series requires say 25mA current you require 75mA current. 0.22uF 400volt cannot give you the required current raise the capacitor value of 2uF instead of 1uF(connect one more 1uF 400v in the above circuit. now you are getting only less than 5mA current in each loop.
Hi i connect the 3 cerise of LED each cerise are 50 LED, i connect IN4007 Diode in Bridge & .22uf/400Volt paralal in 110 K Resistance, each cerise 100 Ohm Resistance But do not Glow Bright,Pl. Help me The Circuit & solb the problem
Hi hari for 19 LEDs in parallel it will be 3volts @ 380mA this calls for a 5uF capacitor in place of 1uF 400volts. 100 ohms should be reduced to 33 ohms 10watts. The 10uF should be raised to 100uF400 volts. You have to use 12volts 10 watt zener diode before 7805. no space and not worth the trouble. buy a 3volt 500mA step down transformer and fit it in the space occupied by the battery. feed the transformer output to the rectifier circuit already present. no need for any other modifications. will be most reliable.
Hi Seetharaman,
I have a chinese make LED lamp with 19LED and a 4V battery earlier. Now the battery failed and I wish to convert it to a mains operated lamp. I have modified it with your circuit with an additional 7805 and 47E at the output to get around 3.0V since LEDs are already soldered in parallel. But the input of 7805 is around 32V. what changes should be made to your circuit to get the output voltage around 10-12V so that 7805 will drive safely LEDs in parallel. The LED is small bright white type and works within 2.6-3.0V and 20ma range.
thank you.
Cheap and best. Thank you very much Sir.
Hi Prabhat you ca use 100LEDs of 3volt 25mA standard white LEDs in the above circuit with just one change of replacing 1uF with 4.4uF (2nos 225k 400 volts in parallel)
cant we use this circuit for 100 LEDs?
Hi Asankap it is better to use 400volts if LED chan is likely to have any dry joint or to test power supply portion without LEDs. i prefer 10uF 400volts as filter capacitor
Dear Seetharaman,
Thanks for your reply
i meant the capacitor after the bridge(electrolytic capacitor).most of the manufactures use 4.7uf 400v cap.i use 80leds(40 in series) and 108leds(54 in series).is 250v capacitor enough or 400v one better?
Thank you
Hi Asankap it should be 0.47uF 400 volts not 4.7uF.
Hi Manoj for 9LEDs use o.47uF 400volts inplace of 1uF 400volts no other change is required.
Thank u Seetharaman Sir for a wonderful circuit. Your circuit is excellent and working perfectly. What are the changes made to reduce the LEDs to 9 nos? Hope you will reply soon.
Regards
MANOJ VJ
Read more: http://www.circuitstoday.com/mains-operated-led-circuit#ixzz1XvawVZ92
Under Creative Commons License: Attribution
Dear Seetharaman,
Thanks for your reply.is 4.7uf 250v electrolytic capacitor enough for 80leds(40 in series)?.is 400v better?
Thank you
Hi Asankap for 3.2 volt 20mA LEDs you have to use 0.47uF instead of 1uF. these resistances are for surge current limitting, hence need not be changed. you can use any non capacitor rated for atleast 400volts. 1N4007 you can use PHILIPS ITT EC etc.
Hi seetharaman,
Just a one question.i am using 5mm 3.2v 20ma bright white leds(i drive them at 16ma to get maximum efficiency).What is the minimum safe resistor values for before and after the bridge rectifier(100 ohms resisters)?
Thank you
Hi seetharaman
thanks for publishing such a valuable circuit.i have few questions regarding this circuit.i had a problem with 1N4007 MIC make and electrolytic capacitor.what are the best brands to use in these energy saving lamps?are nichicon and rubycon good?any specific brand for 1n4007?
there are different sizes and type of Metallized Polyester Film Capacitors.(ex:-cbb21,CL21).so,what is the best type and brand for better life
Thank you
Hi Deepak for red LED maximum is 2volts at 35mA better not to drive at the limits may shorten its life.
Hello sir, thank you for reply!
you have given the rating for 5mm Red LED as 1.7V at 20mA
i want to know that whether it is same for high bright Red LEDs which has appearance like white LEDs when OFF and emits high bright Red light when ON. plz reply!
i want 2 channelor 3or,4 channel led power supply,circuit diagram ,,,,,,,,,,plz sirrrrrrrrr,
Hi Deepak 5 mmRed LEDs will be rated for 1.7 volt at 20mA. for 50 LEDs it will be 85 volts. Reduce 1uF 400 volts to 0.37uF 400volts (0.22 in parallel with 0.15uF, 0.33uF 400volts can also be used) no other change is required.
hello sir,
yes sir i want to connect only 50 nos. of red 5mm LEDs (which has clear glass like outer appearance),so please tell mi what changes should be done in above circuit & component values to make single string of 50 red LEDs. Sorry sir, but i don’t know the current and voltage rating of that red LED so kindly request you that suggest me changes.
Hi Deepak you can connect only one colour per string, as the currents are different for different colour LEDs.
hi sir,
thank u for your reply! Sir please tell mi what changes should be done in above circuit & component values to make single string of 5mm 50nos.of white-to-red LEDs. olz give detail of all changed component & their values.
plz reply!
Hi Deepak you cannot mix up LEDs in serial string as their current ratings are different. you can make 5 different colour individual 5 strings and place the LEDs alternately.
Hi Anish feed 25mA from a constant current source, check for the visual brightness and measure the drop across the LED if it is 3.2 or greater then the LED is normal one. If the drop is just around 2.9volt. increase the current to 50mA, the drop across the LED is between 3.2 and 3.4volt visual brightness level will indicate it is hi bright LED. if you have lux meter feed 50mA to the LED keep the LUX meter at 1 meter distance it should indicate between 180 and 210LUX. if so it is high bright LED.
Thanks Sir. Your circuit is excellent and working perfectly. What are the changes made to reduce the LEDs to 9 nos? Hope you will reply soon.
“RAMZAN GREETINGS”
Regards
MANOJ VJ
Hi Mr.Seetharaman, please do provide a table or something similar so that we can calculate particular capacitance and resistance needed for particular no.of.leds.
BTW i have a bunch of 100 white LEDs So, how do i know whether it is super bright or ordinary LED and how can i estimate its current rating…
Regards
hello sir,
i want to make mains operated lighting for deepawali using led. i want to make —
1)50nos. 5mm white-to-red series led string light
2)50nos. 5mm white-to-blue series led string light
3)50nos. 5mm white-to-green series led string light
so i request you that please tell me all the changes needed to make the all 3 cases i mentioned above. i don’t know the rating of these red, blue & green led’s. therefore i request you that please tell me suitable changes.
waiting for your reply!
Hi Murali increase 1uF to 5uF and reduce both 100 ohms to 33ohms 5watts, increase 10uF 160 volts to 47uF 160 volts no other changes are required
dear sir i want to connect 3 high power led of 3.2v of 350ma pls tell me what r d changes is requir in this circuit
Hi Rohit 56 nos LED 56 X 3.2 is 179.2 volt hence you have to use 250volts capacitor before 160volt is getting blown up.
Hi Capsun In the above circuit you can use 250volts are higher voltage capacitor
For 45 LEDs of 3.2 volt @ 20mA use 0.47uF instead of 1uF. no other change is required.
Iam connecting 45 LEds (3.2v @20mA) .Please suggest the required changes .Thanks in advance
Dear Sir I could only find 10 micro farad 250 vols in my place . Can i use this 10 microfarad/250 volts capacitor .Waiting for reply
Hello Seetharaman,
I made this circuit, with the following changes
-56 nos white led used 3.2v 25mA
-0.47Uf 400v against 1Uf PPC.
-All other components remained the same, the LED’s light up etc., Is this circuit okay, I figure that the 10Uf 160v will not last long, cause I find it getting warm.
Kindly advise.
Thank you sir.
Thanks Sir.
Hi Chetan you can use 10uF 400volt.
Sir, in my circuit the 160 volt 10 uF capacitor has bulged on the top, so can I use 400 volt 10uF capacitor I have found that capacitor in the electronic choke of tube light.. can I use that capacitor.
Hi Yatin is that 72 super white LEDs of 20mA each. you require the same circuit no change is required.
I want 20 mA output.
I want to know which capacitor and register work for 72 led light.
Hi Rohit use the standard formula. f = 1 / (2 pi R C) you will know the reactance for a capacitor you know the number of LEDs its current calculate it resistance you will know what is dropping resistance required. calculate C from the above formula.
Hello Seetharaman,
A basic question,In all Mains operated circuit, the voltage is reduced by capacitance reduction, Hence is there a table some where, where
Example- a 22uf polyester capacitor would provide about 20mA of output current is displayed to make things easier.
Thanks for all your help
regards
thanks sir
Hi Murali change 1uF to 1.5uF. change both 100 ohms to 47 ohms 2 watt. up to 24 LEDs you may not see much change in illumination
Dear sir
i want to make one 10leds and another 16 leds of 8mm, 0.5 watts 100ma leds what are the changes is requir, please help me.
Dear sir
i want to make one 10leds and another 16 leds of 8mm, 0.5 watts 100ma leds what are the changes is requir, please help me.
Hi Kumar Blue is 1uF 400volt polyester / poly-carbonate and orange is 10uF 160volts electrolytic. it is available in Bangalore and Chennai.
Hi Mudassar check your bridge rectifier polarity and check the 1uF it should be non electrolytic check the polarity of 10uF 160volts. If all are OK your bridge rectifier diode may be faulty or connected wrongly.
Hi, Sir what type of capacitor need to be used in above mentioned circuit diagram (10uF 160V) its ploy or some other type. If its 10uF 160V Ploy in above mentioned 3 pictures in 2nd picture what is that blue capacitor used and whether its available in India (Bangalore).
HI sir i assembled this circuit but voltage across bridge diode is 5.3 and voltage across 10uf capacitor is zero,means no voltage, i am using 1uf/250v capacitor, please suggest me the solution, waiting for reply
Hi Kumar if you keep the LED circuit open and switch on, a peak DC of 325 volt will appear across the capacitor and blow it. use 400 volt if you are not confident of your wiring. if the circuit is fully connected without any mistakes then LEDs will glow and capacitor will work without blowing, as the voltage developed across the LEDs are just 72 to 80 volts only.
Hi, 10uF 160V Capacitor got burned why is this problem happening already 3 capacitor got brunt.
Kindly help wait for your reply.
Thanks dear
Hi Saifur the protective resistances have got burnt(120 ohms). This indicates over current drawn by the circuit. This is due to the capacitor 474K. the voltage rating of the capacitor may be low. try to get 400 volt capacitor and use. the 120 ohms 1/2 watt is more than sufficient. with 474K capacitor the current will be 25ma. 25ma through 120 ohms will be hardly 100milli watts.
Dear please check those photos, you may get a clearer view
“what is the current consumption at 3.2volt” I cannot get your question
“What about 10uF 160volt and 1N4007 are they healthy?”
10uF 160volt is burned, and 1N4007 are looking normal, but I don’t know, I give those pictures for your advice
_______________
June 26, 2011 at 8:32 am
You Said:
Hi Saifur These diodes are rated for 3.2 volt @ 20mA. reduce the capacitor from 1uf to 0.47uF. no other modification is required.
________________
I check Led’s packet, & found that they are 3.2 volt, But I cant remember what mA are written in those LED’s packet
____________
I will make this ckt again, But afraid of burned again
Hi Saifur what is the current consumption at 3.2volt. What about 10uF 160volt and 1N4007 are they healthy?
I check LED specification, It is 3.2 volt LED
Please give me some suggestion, so that when I make this project again , then it will not burned.
Dear, today it is not on at all, then I check it, and found it burned, What is you thinking about it? I give some pictures of it, Burned pic, A set of parts,
http://imageshack.us/photo/my-images/220/dsc00004ww.jpg/
Normal View
http://imageshack.us/photo/my-images/96/dsc00005pf.jpg/
Burned
http://imageshack.us/photo/my-images/14/dsc00006sn.jpg/
Burned
http://imageshack.us/photo/my-images/32/dsc00007rh.jpg/
Closed Vied
http://imageshack.us/photo/my-images/17/dsc00013zq.jpg/
Another set of parts,
http://imageshack.us/photo/my-images/811/dsc00015fn.jpg/
Burned View again
I will make it again, want your advice, that It will not burned again, Waiting for your advice, You may guess something after viewing these pictures
I was happy to make such light by my hand which will consume less current.
Dear I appreciate your effort of helping us
Hi Saifur either your 1N4007 are defective or the LED specifications are different. the same is working in my house for last more than a year without and deterioration. in India we found that to be due to defective 1N4007 replacing them with reputed make,made it ok, no LED has failed. you can also remove LEDs feed 3.2 volts and check for the operation of each one if they are good the problem is 1N4007 only.
dear, I made it with your support, & at first It gives nice light, but continue running after 2 hr, It goes totally dim ,
when I switched off the light, then it stops slowly,
What is the problem do you think?
waiting for your support. Now I am frustrated.
these are few pictures of that project
http://imageshack.us/photo/my-images/641/image0011e.jpg/
http://imageshack.us/photo/my-images/155/image0012g.jpg/
http://imageshack.us/photo/my-images/535/image0017vs.jpg/
http://imageshack.us/photo/my-images/84/image0018j.jpg/
thanks dear for your feedback,
Hi Saifur the photos are out of focus, anyway 474 means 470000 that is 470KPF or 0.47uF. if it is rated for 400 volts you can use it.
this one is correct link
http://imageshack.us/photo/my-images/715/capqc.jpg/
Dear seetharaman, I am facing some problem,
as ur suggestion, I buy this capacitor, (seller give me this) check this link . It is correct capacitor? I am confused. you said 1uf to 0.47uF 400volt. But seller give me 1H 474K.
Please check this link to view pic of this capacitor. It is correct one?
http://img715.imageshack.us/img715/3948/capqc.jpg
Hi Saifur These diodes are rated for 3.2 volt @ 20mA. reduce the capacitor from 1uf to 0.47uF. no other modification is required.
Dear Seetharaman
If I use normal 2 pin white LED, is there any problem arise? I am afraid that I will not find that 4 pin bright white LED in my Bangladeshi market. Though I am new, forgive my this type of question
Please suggest.
** Please delete my previous two question please
** 2 pin white LED
Dear Seetharaman
If I use normal 2 pic white LED, is there any problem arise? I am afraid that I will not find that 4 pin bright white LED in my Bangladeshi market. Thought I m news, forgive my this type of question
Please suggest.
Hi Capsun it is due to surge voltage and current.
to avoid this zeners and filter capacitors are used. Still if it is happening the LEDs may not be of the rated capacity. Any standard reputed retailer will be in a position to help you.
Pls tell me which company capacitora,diodes are best.i found some of the LEDs are burning after swiching it on and off several times.May i know the reason for this.
Hi Capsun Replace the polyester capacitor with a good quality 400volt capacitor.
Dear SIr Iam using PCB ,The problem is the brightness is not uniform they are becoming dim for a while and again they become bright.The poly cap becoming very hot.What changes i have to make .Waiting for reply
Hi Capsun 16 LEDs of 3.2 volt is 51.2 volt and each LED dissipates 3.2 X 0.13 = 400milli watts. you have to use proper heat sink PCBs for them. if the generated heat is not properly dissipated they will fail.
Dear Sir they are also becoming dull for few minutes and again become bright .The brightness is not constant.Pls tell me whats wrong in my circuit .Waiting for reply
Dear Sir I have connected 16 LEds (3.2v @130mA) in series .I Increased 1 mfd to 2 mfd, added 33v 1 watt zener 2 in series and parallel to filter also changed 100 ohms to 47 ohms but the LEDs are burning out after few hours.Zener diodes also become fail.What changes i have to make . pls tell me . Waiting for reply
Hi Saifur the above circuit is the corrected one after June 26th the mistake was corrected. yes they are 4 Pin Hi Bright white LEDs 3volt at 50mA.
http://images.blog-u.net/wp-content/uploads/2010/09/Diodes-bridge-Rectifier.jpg
see this picture.. I cant recognize problem in that & your b rectifier, Please clarify dear as I m new.
Is these white LED’s are 4 pin?
as I am new, so I arise this type of question. Waiting for your asnwer
Dear Seetharaman
I am new in electronics, but I can follow the circuit. But in some comments (June 26, 2010 at 2:27 am) you said there is some problem in this ckt, & some diagram may rotate 90 degree. Do you please clearly and corrcet the diagram pls so that I can directly follow the diagram
Sir, I added extra 12 LED’s that is total of 36 LED’s the brightness has been increased.. thank you..
OK sir thank you..
Hi Chetan the same circuit will do. no change is required. As the change in current flow through the LEDs are marginal you will not practically see any brightness change.
sir, for 36 LEDs (3volt @ 50mA) what modification I’ve to make..
Hi Capsun 24 Hi-bright white 4 Pin LEDs (3volt @ 50mA)in 2 rows will replace 11watt PL lamp. 40LEDs in 3 rows will replace 23 watts CFL lamp. May be for 15 watts you require around 30 in 3 rows to take care.
Hi Chetan the same circuit will do for 3.2 volt 50mA Hi Bright 4 Pin LEDs..
Sir, i want to add extra 12 LED’s that is total of 36 LED’s What changes I’ve to make..
Dear Sir I want to replace 15w CFL with LED .How many LEDs i have to use to get same brightness as 15w CFL. What kind of LED should i use .Waiting for reply
Hi Chetan see the figure in the following site. you get the same in India.
http://www.xbhp.com/talkies/universal-threads/11469-convert-ac-dc-bike-all-dc-47.html
Hi Chetan there is a PCB mount available for 150mA LEDs costing around INR 10, you have to use them for each LED.
Sir, what I have to do for the heat sink..can you give me some suggestions please..
Hi Chetan you have to use the PCB with heat sinking track meant cooling these LEDs.
Hi Anish Please refer the General purpose PCB
http://www.delabs-circuits.com/cirdir/electric/electric2.html
Thanks for the reply sir, definitely the bread board is my fault. I have the correct components. where do we get glass fiber pcb’s? and how do they look like? this is the first time i am hearing that name..
Sir, the LED specification are:-
Max. Forward Current: 150mA
Max. Forward Voltage: 4.0V
Working condition: -40°c~+60°c
Hi Anish phenolic bread boards insulation value can handle say up to 100 volt but not greater than that. Hence you use a general purpose glass fiber PCB which can take care. Check the diodes and electrolytic filter capacitor and the 1uF capacitor it should be rated for 400volts. ensure that you are using high bright white LEDs with 50mA @ 3.2 volts.
Hi,
I assembled the circuit, and when powered, the .5 watt resistor connecting the bridge and mains power burnt..(and was burning till i cut the power).. cant troubleshoot the problem.. what may be the possibilities? My friend suggested not to use it on the bread board..
IMO, using bread board is the fault?
Hi Capsun For 16 LEDs you have to use an electrolytic filter capacitor of 220uF 63 volt use 2nos 33volt 1watt zener diodes connected in series and parallel to filter capacitor as surge protector. Use 2uF capacitor instead of 1uF in the supply input.
Hi Chetan Check your LED specifications. test one led with 80mA constant current if it is getting heated up, you require PCB type heat sink for your LEDs. LEDs are around INR30 and the special PCB is INR10.
Sir, the LEDs are becoming very hot..
Dear Sir how to choose the voltage of the electrolyte capacitor .I want to connect 16 LED in series (3.2V@ 130mA).What other components i have to change.Waiting for reply.Thank u
Hi Chetan no change is required the same circuit will do.
Sir, what changes I have to make to get 80mA..
Ok sir i will use polyester type.
Hi Chetan you have to use non polar type, since it is used in AC circuit, getting 1uF non polar electrolytic will be difficult but 1uF polyester is available in plenty in the market, which you can comfortably use.
Sir, can i use 1uF 400v Electrolytic capacitor or polyester type capacitor.
Thank You Sir…
Hio Chetan for 80mA LEDs no change is required.
Sir, i want to get 80mA because 120mA will be high for those LEDs.. So what modification i have to make.
Hi Chetan you can use the same circuit with 24 LEDs of 3.2 volt 120mA 8mm straw hat LEDs. the total power consumed by 24 LEDs will be around 10watts (with 1.68uF).
Sir, so that how much current it will dissipate in each LED and can I use 8mm 0.5 watt straw hat LED..
Hi Chetan increase 1uF polyester to 1.68uF(add a 0.68uF 400volt parallel to 1uF)
Sir, I want to make another circuit…
In the above circuit can i use 8mm 0.5watt straw hat LED which can withstand upto 100Ma..
Hi Jawad use Light from scrap circuit you can use up to 13LEDs without changing any component.
dear sir,
I want to diagram which used 8 Leds on direct 230 vac
Thanks,
@seetharaman, what happen to john??? No new posts here and one of my post under pending?
Increase 1uF to 1.64uF (use 2nos 0.82uF 400volts in parallel). reduce 100 ohms to 47 ohms 2watts. all other components require no change.
Dear Sir I want to connect 10 LEDs (3.2v@ 150mA) in series .Pls tell me what changes shall i make in the circuit.Waiting for reply
Thank you for your kind response sir.
Hi Chetan This circuit will consume around 2.5 to 3watts.
Yes sir, the LEDs are getting little warm.. Sir, i want to know how much watt it will consume..
Hi Chetan readings are looking alright. run the light for about 2 to 3 hours. switch off and check the leds are they little warm or hot. it should be just little warm indicating everything is fine.
Sir, I have used 24 LEDs. The DC voltage and current across EACH LED is 3.14 volt and 17 mA.
HI Chetan how many LEDs you have used? If possible measure DC voltage across one LED. With 1 or 2 LEDs it will be 24mA. with 24LEDs it will just less than 20mA.
Hi sir, i constructed this circuit by using 0.33uF capacitor for 3 volt 20mA LED’s as you said, and they are very bright I don’t know how much current is flowing through those LED’s..
Hi Adru to get 40volt at 1amp you require around 12uF 350volt AC capacitor which will be rare to get and will be quite expensive. these circuits are suited for a maximum value of 2.2uF capacitor i.e. max 120mA at 40 volts. Hence for higher currents use transformers or switching supplies which are best suited.
Hi Chetan reduce 1uF to 0.33uF, no other change is required
Sir, i want to connect 3v 20mA Leds what modifications I have to do. please reply sir because I will construct this one.
WOW wat an active post & itz being one year nearly;regards for sir.seetharaman,mouly,japanjot.
i hv one question:
can v use this circuit as a transformerless dc powersupply for digital circuits,say design it for 40v 1A and placing an LM317 for varying the dc output voltage 1.2-37v.
Atually i dont want bulky transformers :-p
Hi Rajesh 474K, first two are integers like resistance code 4 indicates 10 to the power four as multiplier (simply add 4 zeros) hence it is 470000 pF or 470KPF or 0.47uF. K stands for 5% tolerance and J stands for 5% tolerance.
Sir, how can we read the coding in Polyster capacitor? 474K/400v, 400V474J…etc….
Hi Misra 25mA LEDs will get damaged.
sir,
can i use 50mA & 25mA LED’s mixed in these circuit? is there will occur any problems?
Hi Benny if want full kit you can contact DJR Electronics Chennai. 04442028443, or components without board from Vegakits Mumbai.
Dear Mr.Seetharaman sir, i am interested in this circuit very much… but i am located in a rural area of ponpara ….so the scracity of such electronic components is facing here,,,,, sir, are you a shop dealer of the electronics goods/ electronic items…? i am ready to make payment for the components of the device / please tell me where i can get these components by courier? i am ready to make payment in advance. So please…please help me////
hi Nikolas the bridge circuit is already corrected in the above diagram. what is shown now is correct
Sir Seetharaman, I’d like to ask a silly question (Im a newbie in electronics):
Why the bridge should be rotated 90 degrees clockwise? Is the bridge differ from http://www.circuitstoday.com/mains-operated-led-lamp?
Thanks.
Hi Meodenmatula Use 1uF only or else you will loose your LEDs soon. with 2.2uF the current will be greater than 110mA for 50LEDs.
Hi Seetharaman
I want use 220 Volt AC with 50LED 50ma.
Can i replace capacitor 1uf by 2.2uf. in addition, need to change anything else
Thanks
Hi Capsun for 20 X 1 watt LEDs. Read my reply to Mouly but change capacitor to 4.2uF 400 volts instead of 3.6uF. Any way I will recommend you to connect 4nos 1 watt leds in series, like this you make five sets connect them in parallel and connect it to a readily available 12volt 2amp SMPS.
Hello Sir,I want to make a compound light with 20 high power 1 watt LED’s.Iam new to electronics .what changes i have to make in this circuit.Please help me.Thanks in advance
Hi Mouly You have to use 3.6uF 400 volt in place of 1uF. Use 33 ohms 5 watts in place of 100 ohms. Change 10uF 160 volt to 47uF 400volts.
Dear Sir, I want to coneect 5 high power LED’s (3.2V @350mA) in series.Pls tell me what all the necessary changes i have to make in the circuit.Waiting for reply
Hi Mouly These depends on the make used. Reputed makes may even work for 5 to 10 years. For high voltage protection add 78volt 2watt zener (2nos 39volt 1 watt diodes in series)diode in parallel with 10uF.
Hi Rajesh no change is required except 10uF from 160 volt to 250 volts. no cooling fan is required. use a PCB with thick wider copper track and with good quality soldering should help dissipating the heat generated nicely.
Dear Sir ,what is the life span of the poly capacitor,also the 10uf electrolytic capacitor.How long they work ?Can this circuit withstand high voltages?Waiting for reply
Hi Seetharaman sir, i created the above circuit for outdoor use with a 8 x 8 Matrix in a PCB, all the LED’s are 50mA. What are the other changes should i made in the above said circuit for the 50mA LED x 64 nos? please clarify the poly. cap values and other resistor/ capacitor values. I planned to place in a closed outdoor light fitting to safe it from rain. Should i add some cooling fan’s for the 64nos included? Please clarify…. thanks in advance for your valuable reply
Hi Mohanraj
use both the foromulae for your calculation, use RMS value.
the values are 230 volt 50Hz.
use the formulae
R = V / I (the voltage you want to drop with current flow required) AND substitute R in the following formula.
f = 1 / (2pi R X C) to calculate capacitance.
Dear sir
How to calculate capasitance value and all resistor value in the above circuit diagram if there is any formula for each please replay me sir
Hi Arie this circuit is suitable for 50mA hi bright LEDS which can stand 75mA. If you are using Hi bright whie 25ma LEDs donot exceed 35mA. Hence I will prefer you to reduce 1uF to 0.47uF. Check 1N4007 diodes some consignments available in the market are bad, they cannot stans more than 100volt. May be 1N4002!?. my prototypes (10 pieces) still running safe at home. The brightness is much better than 11watt energy saver u type tube.
ARIE, dont use mic make diodes, use other makes which has thick leads. And the above ckt works without any problem if u use quality components check ur LED voltage and current this circuit is for 3.2v,50mA. if ur LED’s are 20mA it i’ll get fade soon…
BENOY if u r using 2core cable for 4ft then the conductor loss may present. it,d be better if u use fine thin wire bcos it has less copper so loss ll be less
hi, I am trying to string it, for R.. I replace it with 1 watt. I tried it just two days … with the condition led to live, not hot component, but on the first day .. 8 led start to fade, for 16 other led is still burning brightly. And flame equal to 24 LED lights 7 watts, still less bright? and how many led to the pair to be burning brightly?. how the power output by 24 led?
Hi Seetharaman sir, Primarily a Hats off! I’m eagerly searching for a LED Lighting sys for my ‘dark’ room( actually an extension of my home is become cloudy with out proper windows!). I found it.. Am in doubt that can I set the 24 no. series with a 4 feet partitioning? ie, shall i set the LED’s series in 2 by lagging the 12 LED’s after 4 feet gap(with a 2 core cable? is it will make any wrong result? Please reply
Thanks in advance
hi pramugan 5uF is capable of 360mA current. since you have used a 50volt capacitor it has become leaky above that voltage hence 50 / 3.2 = 16 LEDs can glow beyond that the capacitor should have become hot.
with 160 volt capacitor 160 / 3.2 around 50LEDs. the filter capacitor is acting like a resistance at higher voltage.
in the above circuit with 5uF 350volt capacitor in the input and 10uF 350 volt as filter you can connect 108 LEDs in series.
when i ll be getting reply for my post
yes mouly calculate the capacitance value according to ur requirement.
Dear sir
Is that possible to get output above 150mA so that i can light up high power LEds in series from the mains supply
sir my doubt is by changing filter capacitor will the output increase?. because i construct bridge with 5ufd 400v as input capacitor and 1000ufd 50v as filter it can able to lightup 16 LEDs i replaced the 1000ufd 50v with 63ufd 160v it can able to lightup 48 LEDs.(all connections in series). in general is that possible in similar circuits?
thank you sir
Hi Kumar use 2nos 40volt varistors in series in parallel with 10uF 160 Volt.47uF will get still hotter. use a good quality 160 volt or use 10uF 250volt. nothing is required at the bridge input if you ate using in DC.
the varistor avail is 40volt and next to that is 175 volt. instead of that 75 volt 1 watt and 3.3 volt 1 watt zener in series and in parallel with 47uf 160 volt( i replaced 10uf 160volt with 47uf 160volt bcos 10uf became very hot). And should i have to connect both mov at bridge AC input and zener at filter capacitor?
Hi Kumar Your poin 1 is ok, for SMD LEDs you can use normal components no need for smd components. you can use a 270 volt varistor across the bridge rectifier AC points( input surge protection). 2nos 30 volt 1w and 1no 18 volt 1w zeners connected in series in parallel with 10uF 160 volt capacitor(towards 1uF capacitor leakage protection) or you can use a 76 volt varistor if available readily. s10k320e is a 320 volt mov. should not give any problem not suited for this circuit as it may not protect.
•Hi sir, I tried your circuit its working great . i used 5mfd @ input for 150 Led’s. 50 in each row.
1. how to specify the suped flux 5mm Led which
is displayed in the above picture 07 does it has any model number?.
2.if i use SMT Led can i use the same circuit or should i have to go for SMD components?
3.how to use VARISTOR in the above circuit ?
Thanks a lot for sharing ur valuable time and ideas..
i connected a mov S10K320E b/w ph and netural but it made all the LED’s to dim so i removed it what is the value i should go for and where to connect it.
250V is just ok, try to get a 400V one.
i don’t have 1uf 400v. could i use 1uf 250v? is it safe or will be burning?
i connected a mov S10K320E b/w ph and netural but it made all the LED’s to dim so i removed it what is the value i should go for and where to connect it.
Hi sir, I tried your circuit its working great . i used 5mfd @ input for 150 Led’s. 50 in each row.
1. how to specify the suped flux 5mm Led which
is displayed in the above picture 07 does it has any model number?.
2.if i use SMT Led can i use the same circuit or should i have to go for SMD components?
3.how to use VARISTOR in the above circuit ?
Thanks a lot for sharing ur valuable time and ideas..
thanks nice posting
yup thank u…
Hio Rahul the required effective 750 ohms is given by the capacitor(this will be effective resistance value of the capacitor at 50 Hz). There is no need to calculate 100 ohms 2nos value, as it will be standard for all circuits to limit in rush current to 1amp max. hope i am clear
i got it sir 4.7mfd and resistance is b/w 200 to 470k
sir waiting for ur reply plz help me out
Sir am waiting for your reply kindly plz help me out
thank u sir actuallt i need to improve brightness so am adding 150 led’s of 3.5v@ 25mA 50 in each row. am confused with the calculation.50×3.5=175. 230-175=55. 3 rows in parallel so 25mAx3=75mA.since parallel current varies. so 55v @ 75mA, 55/0.075=733.34 ohms. in f=1/(2*pie*R*C) R= v drop/I =55/.075=733.34 ohms. then 50=1/(2*3.14*733.34*C) =4.3mfd. therefore standard values are 750 ohms and 5 mfd is this correct?.
Hi Rahul you require 1.2uF and 200 ohms only 3k is not required. say you are using 16 LEDs of 3.0 volt 50mA 48 volt at 50 mA you have to drop 230 – 48 volt that is 182 volt at 50mA (RMS value used for calculation) hence 182 / 0.05 that is the series resistance required. 3.64K ohms. this is Xc now calculate the required C from this freq is 50Hz. for 50 Hz thumb rule for filter capacitor is 1000uF per amp of load, for 50mA load 50uF is required to reduce flicker. 10uF is practically found sufficient without any noticeable flicker. To avoid switch on surge current to be well within the limit of 1amp 220 ohms is the preferred value.
Hi Ketha it is possible. we are trying to limit it to 90 high bright LEDs (30 in each row)with a rotational possibility of 90deg continuously, it will appear soon.
sir i used 25 white led in a energency light light and i used 5 x 1.2v 2200mah batteries and i connected 4.7 ohm’s 10watts resistance due to this the battery drains very quickly how to modify the circuit. charging side is working good.but load side is worst. plz help me out.
how to calculate filter capacitor sir (ie. 10mfd 160v). i designed a circuit with 680 and 1000mfd 50v for 16 led’s. without knowing the calculation only i did but its working fine, but i think its a bigger value for the ckt. i used 105j 400v poly parallel with 1k ohm and 56 ohm mext to the bridge. i just want to know how to calculate it.
if my calculation is correct t have to use 1 or 1.2mfd and 3k resistance. before bridge.isn’t sir. and the remaining two 100 ohm’s and filter capacitor should remain the same. am i right sir??
Hi Rahul you kindly go through my comments dated nov6th and 16th will give you the details
sir it is possible to design led tube circuit as in this link http://www.leds.edn.com/blog/leds-blog/what%E2%80%99s-inside-led-tube-light-teardown
from input
1st set |->->->-|
2nd set |->->->-|
3rd set |->->->-|
hi sir
i just want to know that how to calculate poly capacitor farad and voltage. and if i construct the circuit for 60mA is that possible to connect 50 led in a set and 3 sets in parallel. |->->->-|
|->->->-|
|->->->-| like this .
Hi Prasanth intially like energy saver lamp it will be expensive but on the long run it will pay back on electricity expenses.
Hi Dhruv you can use higher wattage resistances if space is not at premium.
hi sir im new to electronics and i like your project very much i just want to know that in any circuit or in your circuit also can i use high wattage resistor even circuit required low wattage resistance….in ur circuit can i use both 100 ohm resistor or 0.5 watts….instead of one 0.25 watt 100ohm resistor…waiting for ur reply sir
Thanks a ton Mr.Seetharaman!
wondering if it would be economical to do so.
I was searching for such a thing for a long time. I will now replace all the bulbs in my home
Dear Sir,
The LED circuits are very interesting and use full to me. I hope you will publish low cost LED circuit diagrams later.
Thanking you
yours faithfully,
UDAYAN
The LEDs are High bright white 3volt 50mA type. 1uF should be non electrolytic, paper, polyster or polycarbonate. Open circuit DC at bridge rectifier output will be around 350volt. but if all LEDs and components are connected it will be around 72 to 75 volts only.
i also tried the new version but i am getting the voltage about 230 v at load.
is it correct?
ok thnx sir,
Q…. we have to use the electrolytic capacitor{1 mf 400v} only or we can use any other.
and plz tell me the voltage at the o/p of bridge,and also tell me the voltage and current rating of the LED.
Hi Rahul there was a mistake you kindly see my earlier comment of june 26th on that, it has to rotated clockwise by 90deg. otherwise the circuit is ok and functioning well.
how the bridge is working ?
plz tell me
Hi Sir, can i add LEDs until it has 36 LEDs in series? What are the components value to change?
Thank You
Eason
Hi Japanjot you can suitably adopt battery charger using SCR circuit appeared earlier in circuitstoday. use the following link.
http://www.circuitstoday.com/battery-charger-circuit-using-scr
ok sir,thnx for the battery charger advice, sir also tell me how to make it overcharge prtective, like the battery should stop charging when the battery is full
Hi Mr Seetharaman, can i add more LEDs to increase the brightness? Can i have a circuit that have two parallel strings with each strings having 20 LEDs(Total LEDs will then be 40).
Thank You
Hi Murali use both the foromulae for your calculation, use RMS value.
the values are 230 volt 50Hz.
use the formulae
R = V / I (the voltage you want to drop with current flow required) AND
f = 1 / (2pi R X C)
Hi Murali you can use as indicated by me on 15th Nov.
Hi Satyam this is a standard formula available in any text book. f=1/(2*3.14*R*C)
Hello Sir, your formula is not so clear, Is it f=1/2*3.14(pi)*R*C OR f=1/(2*3.14*R*C)
all leds r 3.2v max 3.6v
all leds r 3.2 to 3.6 voltage sir
Hi Mr Seetharaman, can i add more LEDs to increase the brightness? Can i have a circuit that have two parallel strings with each strings having 20 LEDs(Total LEDs will then be 40).
Thank You
thankyou sir yes iam planning to use 5mm 3v 20ma, help me for 24led & 36led of same rating
Hi Murali use 0.68uF for 1uF all others don’t require any change. (hope you are planning to use 3volt 20mA white LEDs).
i want to connect 48 5mm leds of 20ma each what should i change in this circuit please tell me sir
Hi Japanjot yes you can make it. 1.3AH battery requires 130mA charging current now calculate for 130mA RMS current that is 230 / 0.13 with 1.8mF you can get it. if not you can use available 2uF or 1uF 2nos in parallel. instead of LEDs you connect the battery. use a 4.7 volt zener to limit the battery terminal voltage from raising.
ya i checkd they are of 3.2v 25ma, sir how to charge 4v battery of 1.3 amp, i want to charge it around 150ma per hour, i want to make transformerless supply like this for it.thank you
Hi japanjot congrats. hope the LEDs are 3.2 volt 25mA that is 0.025A, your calculation is also correct for peak current calculation.
and sir while calculating R for f=1/2pi.R.C the voltage i used is 320v for calculating v in v=ir,320 v dc v
sir i am running 100 blue leds in series, and all i modifies is just i added 3.3uf cap parallel to 1uf cap in your circuit, the total power is around 5w, and leds are quite bright
the leds which i used were 3.17 to 3.20v @ 0.22-0.28 ma
thnks sir 4 this usefull ckt
Hi Japanjot you try and give me a feed back about your success.
*=>>sir with 2uf cap can i connect 60×2 chains of blue led of 25-28 ma ???? total of 120 leds?
*=>> sir what is the maximum limit of dc voltage which we can use for leds ??? when i check o/p voltage withot load its around 345v, so can i use 100 leds in series(3v each and 30ma current) to utilise 300v out of 340 with 2.4uf capacitor??
Hi Japanjot. The 100 ohms are only for input current limitation they donot require any change. The discharge resistance can be any value from 100 to 470 K such that they dont add up the current flow and dissipate power. 10uF will remain the same.
*=>>sir with 2uf cap can i connect 60×2 chains of blue led of 25-28 ma ???? total of 120 leds?
*=>> sir what is the maximum limit of dc voltage which we can use for leds ??? when i check o/p voltage withot load its around 345v, so can i use 100 leds in series(3v each and 30ma current) to utilise 300v out of 340 with 2.4uf capacitor??
*=>> how to calculate capacitor’s discharge resistor. and other two resistors and their wattage (100ohm 0.5w in your ckt)
thank you sir , you always reply with patience
one more thing sir, how much volts can we use for leds, like for 24 we using 72 volts , can we use till 230 volts for 76 leds?
ok thank you sir now my circuit is working fine i am using your same circuit with 2 parallel chains of 28 blue led total 56 leds, they are absolutly fine. thank you
sir how u calculate resistance which is parallel to capacitor?
and if the dropping resistor value comes to be 6 kohm, then do i have to change all the 3 resistance to 6 k ohm or the one which is directly connected to 230v(100 ohm in your ckt) or the resistance which is next to the bridge(100 ohm in your ckt) ?
and the 10 uf cap would remain same in all the cases i guess?
Hi Tony with the recommended LEDs connected the terminal voltage cannot raise beyond 72 volts. by using a low current LEDs the drop across capacitor 1uF will be less hence high voltage will appear across the capacitor and inturn on LEDs. as lesser drop across capacitor higher voltage has devoloped highed current for the LEDs hence they have blown.
please go through the calculations i have given earlier today.
Hi Seetharaman,
If rotated by 90deg than the output voltage at this point capacitor 10uf 160v will be very high 228v – 230v without attached to LED’s and this capacitor start become hot.
No wonder Mr.Japanjot LED’s burn.
Hi Tony in my above circuit the bridge rectifier has to be rotated by 90deg it is a mistake.
Hi Seetharaman,
I tested all the component is o.k, it is because of the diode direction (1N4007) ?
Hi Tony it looks your capacitor is shorted, reason without load the peak terminal voltage can raise to 230 X 1.414 = 325 volts. hence you have to use a 400volt capacitor without load. if loaded 160 is sufficient as you are likely to get around 75volts.
Hi Seetharaman,
I try to assemble the circuit as above and I measure the DC voltage 0 no reading at capacitor 10uf 160v, do I miss something I’m using 1N4007 diode. What is the reading at this point before connecting to LED.
Hi Japanjot This circuit will work with 3 volt 50mA BRIGHT WHITE LEDs. If you want for any other current you have to recalculate. Say you want to use 25 blue LEDs of 4 volt @ 25 mA. 4 X 25 = 100volt at 25mA your supply voltage is say 250volt at 50Hz. Now you have to drop 250 – 100 = 150 volt. 150 volt the current through is 25mA then the dropping resistance value is 150 / .025 = 6 kilo ohms. by using the formula the capacitance required is 0.53uF use a standard nearby available value 0.47uF, by which the current will get reduced to 22mA which will not reduce the glow appreciably, also safe for the LEDs to be driven with slightly lower current.
sir happy diwali to you and your family, wish u had eco frndly diwali with led lyts
helo sir, i made dis circuit with blue 25 leds it workd fine for first time, but as i switchd of and again powerd on all the leds got burnt
…… sir wt to do??
sir plz explain me how to imply your formula f =1/2piR.C,
there are 3 resistances, two capacitors in this circuit ,please tell me how to calculate each component value.
also tell me how to calculate led number acording to capacitance, and how to calculate capacitane according to voltage
please xplain with example, i am very eager to learn and i dont want to burn leds again
.
thank you again sir for your concern
Hi Tony any size 3volt 50mA LEDs.
Hi Seetharaman,
This circuit suitable for 5mm or 10mm LED ? Thanks
Hi Tony you can use switched mode power supply available for 12 volt halogen lamps(they are available in various load ratings). you can use 4 hi bright white LEDs in series and connect it to SMPS through 5 ohms resistance in series with each group as currnet limitting resistance. each group requires 12 volt at 50mA. If you use 100 groups you require 60watt SMPS to take care of all these 400 LEDs. You can increase or decrease in the order of 4 LEDs group.
Hi Seetharaman,
Thank you Sir for your valuable information and if want to increase the LED from 24 nos to maybe 300 or 400 nos how to do it like what China manufacture sell it call LED Flood lamp?
Hi Tony this has been installed in Hotel Lounges and Rest rooms and they are working for the last 1 year without any problem. initially we had problem with 1N4007 MIC make(light will become dim and start flickering). and the electrolytic capacitor(which use to get ruptured). We have switched over to Philips and Keltron, since last one year no problem at all.
Hi Luis for 115volt 60Hz you replace 1uF 400 volt with 0.82 uF or use the same 1uF increase LEDs to 35 nos.
If you want to use one LED for just mains indication use a 4.7 K resistance 3 watts in series and a diode 1N4007 in reverse biased condition across LED. you can use 0.47uF for 1uF and use only 1LED all other components are same.
Hi Guys out there,
So far how many of you try this circuit and can last how long the LED’s, 6month or 5 years?
Les agradeceria me indicaran como calcular los valores de los componentes para un suministro de Red de 115 V AC
Hi Japanjot you can use 2volt (1.7 volt at 20mA)red leds SAY YOU WANT TO USE 40NUMBERS then the voltage is 68 volt at 20mA. retain increase 100 ohms before bridge rectifier as 220 0hms and capacitor as 0.33uF (330nF)
For yellow and green (they are 2volt devices at 20mA)say for 35 LEDs 35 X 2 = 70 volts. the same modification will do.
what would be the changes to be made if i want to install red led of 2v each or yellow led of 2.2v each in this circuit insted of white 3.5v
Hi Japanjot these 28 to30mA LEDs are safe with 25mA hence in the above circuit you have to change 1uF 400 volt to 470nF 400 volt and 100 ohms resistance before bridge rectifier as 220ohms, other components kept un changed. for 60mA change 1uF to 1.2uF no other component requires change. the values are 230 volt 50Hz. use the formulae R = V / I AND f = 1 / 2pi R X C
Seetharaman sir,
How can I measure its wattage, My Multimeter is a low profile one, it can only detect ac rms value of voltage and dc voltage and dc current.
one more thing, i checkd my leds , they are of 28 to 30 ma current each what to do?
any changes are to be made?
and can u tell me the changes to be made for total 60 ma output
please answer all my question in this and my last post…
really thanks alot
ok thnx sir,
1): what would be the value of frequency here would it be 50?, and
2):how you set the current in this circuit, i mean wts the formula for setting desired current like 30 ma, 50, 100, 150 ma etc
3):what would be the changes to be made if i want to install red led of 2v each or yellow led of 2.2v each in this circuit insted of white 3.5v…
thnk you sir, and would be eagerly waiting for your helping hand
Seetharaman,
I’ve used 0.68 uF instead of 1uF for the mains supply and no resistance with it. Yet it worked, with little less brightness. There was 48 LED-s in series. I used a bridge rectifier package.
I will be happy if there is any brightness control, and what is the probable power consumption?
Sorry Japanjot. there was a mistake. it should be f = 1 / 2pi R C. f is frequency R resistance and C is capacitance
sir what is f and F in the formula
Hi Japanjot you can glow 60nos 50mA high bright white LEDs in the above circuit with 2uF capacitor.
The formula is f = 1 / 2 pi F C
sir how many leds can glow with 2 uf cap? can u tell me the for mulas with which u calculate resistances and capacitance for this circuit.thank you again
thank you sir for your quick reply
Sir,
Its working fine. Thank you.
sir,
I have assembled the circuit and working fine. But The LEDs gets faded out within 2-3weeks time. Is there any thing wrong
thankyou sir
murali
Hi Murali nothing requires any change other than capacitor. For 0.82 you can use 680K and 100K in parallel. for 1.2k you can use 680k and 470k in prallel. a small difference in current will not matter much. With 680k and 19LEDs the current flow through leDs will be 48mA which is ok.
Hi Japanjot for 50 LEDs you replace 1uF with 1.5uF. for 100 LEDs use two circuits as above with 1.5uF capacitors
i connected 19 led with 680k capacitor its working will there be any problem or i have to change anything in d circuit
regards
murali
iam not able to get 0.82uf & 1.2uf capacitor a got only 220k, 470k, 680k, capacitor what should i do
sir was looking for project lyk yours for very long, sir what to change for 100 leds and 50 leds.
Hi Murali for 19 LEDs reduce capacitor to 0.82uF, a standard value or use a 15volt in series with th LED loop.
For 42 LEDs increase capacitor to 1.2uF you will get around 47mA current there will not be much of brightness reduction can be noticed.
i bought 2 led plastic housing but in that i can only fix 19 & 42 leds of 50ma what should i change in this circuit thanks for ur reply
regards
murali
Hi Sethumadhavan check the capacitor 10uF for a short. disconnect 10uF measure the pulslating DC with AC and DC content with a multimeter if it is ok replace the 10uF after connecting LED circuit energise it should work. you can use without 10uF also for a short duration during check. without this also LEDs will glow. this is used for switch on surge protection. finally connect it back. (check each LED seperately with 3 volt supply – use a lithium disc cell for fast checking)
Hello Sir,
I’ve noticed already before assembly and done it in right way.
Hi Sethumadhavan the above bridge circuit is wrong kindly rotate it by 90 deg. this may be the reason
Thank you Sir,
I’ve used bridge instead of 1N4007. The LED’s are not glowing. How I can trouble shoot it? I’ve disconnected the supply to the LEDs but not receiving any the voltage? Can you pl guide me?
Regards,
Sethu
Hi Sethumadhavan No load output voltage will be mains voltage X root 2. that is approximately 350volts DC. which will damage the capacitor instantly or if the capacitor is ok then the current limitting resistors 100 ohms will get burnt.
thank u sir for ur reply
Hi Murali you require to change only the 1uF capacitor.
For 15 LEDs it should be 0.77uF ( 2 1.5uF in series)and for 36 LEDs it should be 1.2uF
Dear Mr. Seetharaman,
What will be the no load o/p voltage and the current (disconnecting the LED) across 10µf / 100V capacitor?
thank u sir, i tried this 24 leds circuit today its working fine & very bright/ for 15led & 36 led of 50ma what should i change in this circuit. waiting for ur reply i once again thank u sir
thankyou sir
Hi Ravi you want to use this circuit with the UPS of computer for the glow, yes you can go ahead
Hi sir can I use this circuit for sinewave inverter those are used for computer.
Hi Patrick since all the LEDs are in series you require around 72 volt DC, hence we have to redesign the circuit to suit either 6 volt or 12 volt battery. i will keep in mind for the future project.
Hi Seetharaman,
This is a good circuit(transformer less) mains operated LED CIRCUIT. but just to take a step further if a Battery say 6v 4ah is added to make it mains operated LED with battery back up. would there be much changes required in the circuit.
Regards
Hi Ravi Sorry the bridge rectifier is drawn wrongly. please rotate it by 90deg.
Pl refer to my comment dated 26th june
Good evening sir if Bridge connected as usual what happen’s, please suggest me
thanks Sir
Hi Mouly with capacitance in circuit it is +0.3 hence you have to add inductance also. this will become bulky. to avoid that you can shift to switched mode power supply then you can achieve almost unity power factor but the circuit will become expensive.
Can the power factor of this circuit be around 0.9.how to improve power factor of this circuit.In simulation the power factor of above circuit is just 0.3 .how to make it 0.9
Being a capacitive load power factor will be positive and quite low in value. The power measured was so low and hardly 3watts.
What is the power factor for this circuit Sir.What is the best power factor in case of AC to DC conversion circuits without using transformers.Please explain me about power factor.Waiting for reply
Hi KVS, Please refer my reply on 26th june on correction to bridge rectifier it should be rorated be 90 deg clockwise. you may please go ahead it will work nicely. See my prototype units photographs.
is this circuit is correct? in the bridge side sir? the input ac supply is connected to anode and cathode point of the bridge circuit in other circuits.
please tell me sir. i’m bought the all components and assembled. but finally i check the circuit, i got this doubt.
please tell me soon.
Thanks for your response Sir
It is the peak charge current limitation for the capacitor. wihtout this it’s internal resistance will be zero initially hence the initial charging current will become infinite exploding the capacitor instantly. refer capacitor manufacturers catalog for the recommended max current.
what is the formula to calculate the resistor to limit the peak charging current
Hi Mouly it is to limit the peak charging current to well within 2Amps
How to calculate that resistor (100 ohms) value.Waiting for reply
Thanks for your response sir why is another resistor is connected to other end of 23o volts(100 ohms).waiting for reply
Hi Mouly use the standard formula f = 1 / 2 pi r c. Discharging resistance must be capable of discharging the capacitor in few seconds.
1F will give 1A for 1sec.
Sir,
How to calculate the value of the ploy capacitor for the above circuit like wise the resistor value in parallel to it.Waiting for reply Sir
Hi Ganesh
Hope you require this for 120Volt 60Hz then the only change is increase 1uF 400volt to 3.3uF 250 volts even 400 volts can be used. All other components are same
Sir,
How to use this circuit for 120 v power supply?
Please configure
Thanks
Ganesh
Thank you Sir
thanks for ac led circuits
Hi Mouly If the LED strips are for 25mA, then you can connect two in parallel. if it is for 50mA each then you have to double the input capacitor to 2uF.
Thank you for you response sir.Can I connect two parallel led strips each with 24 leds if so should I change any components.waiting for reply
Hi Mouly 470K to discharge the 1uF capacitor after switch off. The resistances are for limitting the in rush current due to the 1uF capacitor. Since the circuit is for 50mA LED 100 ohms 1/4 watt is required, as the light is enclosed a 1/2 watts resistance to be used. 1uF capacitor is calculated from the Xc required for the current required and the voltage drop required. the 10uF capacitor is for to get a slow raise of voltage and current to LEDs to protect then as they are in series.
Very nice circuit sir .How to calculate the components vaules.What is the use of 470k ,how to calculate similarly other two resistors.please let me know.waiting for reply
Hi friends there was an some doubts about the circuit. Please note.
. 50mA is the current through the circuit. That is 0.05 X 0.05 X100 That is 0.25 watts hence 1/2 watt will do. similarly for 470K 0.25 watts will do.
With the capacitor value shown the limitation is 24 LEDs.
In the place of bridge 400C1 bridge you can use 4 nos 1N4007 since its PIV is 1000volt.
Minimum PIV required is 600volts.
The 100 ohms resistances used are for surge limitting
470K to discharge the capacitor and the 10uF in the DC to protect during initial surge current. All the components used have purpose plese donot delete any you may loose your valuble LEDs on the long run.
why are all the LED’s connected in series..the voltage across each of them will not be the same…isn’t it better to connect all the LED’s in parallel with an appropriate resistor so that all LED’s have the same voltage across them..
circuit radio
circuit fm am