Testing Capacitors In Hindi [ Indian National Language ]  - Page 1
Forum section: electronics / general

author: Amarbir[Lynx-India]
author_rank: Frequent Contributor
timestamp: August 13, 2012, 12:29:47 am
content: Friends ,I Have Attempted To Make a Youtube Video Regarding Testing Of Capacitors With Analogue , Digital And ESR Meter .The Main Thing I Wanted To Tell My Indian Electronic Buffs Who Repair Motherboards , LCD , CRT , Laptops ,SMPS Etc Is How To Use a ESR Meter .I Hope People Who Know Hindi Would Be Able To Comment .

author: korborh
author_rank: Contributor
timestamp: August 13, 2012, 07:51:41 pm
content: Amarbir, thanks for the video and sharing this. Very informative and well delivered!I am in the market for an LCR meter which should do ESR.

author: Amarbir[Lynx-India]
author_rank: Frequent Contributor
timestamp: August 13, 2012, 08:37:37 pm
content: Quote from: korborh on August 13, 2012, 07:51:41 pmYou know i have a tongui LCR .Its good enough but when to test caps with different frequency it gives different values "It should infact ".i need to learn more about that meter i hardly use it .i would suggest you buy a good multimeter with capacitor/inductance testing range and then buy a esr meter seperately .As you will mostly use your multimeter max

author: PA4TIM
author_rank: Super Contributor
timestamp: August 13, 2012, 09:53:39 pm
content: I do not know hindi so it did not look but i have made a sort of hobby measuring capacitors.I designed and builded an ESR meter, used VNA's , RF-IV, impedance and LCR bridges. Compared several ESR methodes and measured a lot on known bad caps ( very educational and gives you a whole new perspective on the importance of ESR)A few things are important.-capacitance-DC leakage-ESR-ESL ( if you are tlking high frequency)The first three things can go bad. All together or just one of them while the others are still good, so just measuring ESR is not wise.I repaired a dvd recorder that had 34 bad caps. 1 leaking DC, 2 had high ESR, the rest lost capacitance.Repaired a satelite receiver. 8 bad caps, 3 had bad ESR but only my analoge meter found three, the other ESR meters, VNA's and bridges found them OK. Why found the analoge meter them ? Because the test voltage was higher, it measures not with AC and it monitors the ESR over a long periode ( if I want, and that I do or fun. The ESR was low, then suddenly goes up, stayes there a while and then dropped. I researched them and one was a mechanical failure, the other probably chemical.( oh, I do not use the meters to find the bad ones, I just examine them after the repair, the bad ones i found using a scope, that is why i knew those two were bad. Using an ESR meter and LCR meterI would not have found them.)ESR is frequency dependent. It is at its minimum at the selfresonant frequency. Before and after that it rises. This is partly meachanical and part chemical. Things like changing delectric constants, ESL, skin effect, copper and aluminium resistnce, thermic effects from different metals touching ect.So measuring at 1KHz will give a while different value as at 100 KHz for the same cap.They give the ESR for a certain frequency. Most times 1KHz but also 120Hz or 200 KHz.So without a new cap from the same brand, type, value, or datasheet, the ESR is a meaningless measurement other then a quick test to find a very bad cap you eould kso had found measuring with a scope ( thats why i use an analog meter, the deflection behavour tells me often more as the value.)I use it during restaurations. After reforming the cap, measuring the capacitance I measure ESR.If i measure in circuit i lift one leg of the cap.Low ESR is not a norm, brand X can have a normal cap with an ESR that is lower as a low ESR cap from an other brand. They are free to name it as they like.Personally i think we used to have low ESR caps until they became cheaper and cheaper so they started to make good caps again and called that low ESRThere is an other factor for measuring the quality of caps. That is the loss angle. It can be written in several forms. Advanced bridges show " 90-loss phase angle" Most bridges use D or DF, the dissipation factor. The ratio between the Xc ( reactance) and the ESR. This is mathematical deducted from the loss angle. This is a better methode because it is not as huge frequency dependent as ESR. But the ratio alone is also useless. 10 mOhm ESR at a Xc that is 100 mOhm is a DF = 0.1 but if the Xc meaured is 1 ohm at that frequency the D will be 0.01. Sounds a lot better and it is but ESR is the same. D tells you at 0.01 that 1% of the power is dissipated in the cap.ESR only tells you it is 10 mOhm. ( D = DF = Rs/Xc = tan pi = 1/Q. And Rs is ESR)But to get the ESR you need to know the reactance. But that is made out of two parts. Inductive and capacitive. Atypival electrolyte with 1 or two cm legs will have 5 to 10 nH selfinductance. But this can be much higher due to the construction. If you measure at 100 KHz a 1000 uF cap the Xc is -j0.00159 ohm, 1 nH is j0.0006 ohm. So your meter sees - j0.00099 ohm and think it is measuring 1600 uF and that with only 1 nH. My peak measures at 200KHz..... So if that cap lost capacitance and your meter reads 900 uF at 100KHz , the real capacitance is much, much lower.That is why you want a lcr meter that measures at a low frequency to know the real capacitance and D. Or a separate ESR meter ( or a scope and squarewave generator, then ESL does not polute the measurement ( several ESR meters do not measure the ESR, because that is a floating voltdrop and must be meaured differential and not by a diodedetector against ground)Sorry for the long text but I allways get a bit exited talking abou ESR. On my side i have several articles about testing capacitors ( most allready translated in English, or an English text under the Dutch one. Most times with pictures from measurements, simulations as check ect.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: August 13, 2012, 11:28:08 pm
content: It's all Greek to me.

author: Amarbir[Lynx-India]
author_rank: Frequent Contributor
timestamp: August 14, 2012, 04:48:23 am
content: Quote from: PA4TIM on August 13, 2012, 09:53:39 pmWell,Thats one solid discussion sir .thanks a tonn

author: nukie
author_rank: Frequent Contributor
timestamp: August 15, 2012, 10:52:06 am
content: That's why full functionality LCR cost $$$$tapatalk

author: Amarbir[Lynx-India]
author_rank: Frequent Contributor
timestamp: August 15, 2012, 10:57:56 am
content: Quote from: nukie on August 15, 2012, 10:52:06 amSir ,Which Once You Have .I Will have a Proper Review of This And The Creatronica Once i get the analog one also in hand