Just a few things I noticed in this video that seemed wrong, or which may have been over-simplified to the point of being misleading: - ESR is only supposed to mean Equivalent Series Resistance, and it is a complex value incorporating a number of things about the capacitor internals. And, as stated, it is frequency dependent. However, in the usual models, it is meant to NOT include leakage, as that is parallel rather than series. So the sketch of a resistor in parallel with the ideal capacitor could be considered to be misleading or confusing. - The equivalent parallel resistance (across the ideal capacitor) should have infinite resistance, so a DCR reading should be a high Ohms value. ESR values should be very low, less than an Ohm for most electrolytic capacitors. High ESR values in an aluminum electrolytic are typically due to drying out and/or breakdown of the dielectric, while low DCR values are typically due to failure of the internal metallic structure of the cap. - Better ESR (or LCR) meters have separate ESR and DCR (DC resistance) modes, and in DCR mode they are testing for that leakage. Indeed, some LSR meters that test DCR will do that test first, and only proceed to testing ESR if the DCR measurement is OK. This is because even a very leaky (fails the DCR test) capacitor might still pass an ESR test. - With this model of tester, is is probably best to always use the printed ESR chart, since the go/no-go message on the LCD screen is ONLY for aluminum electrolytic capacitors rated for about 25V. Testing any other kind or voltage of capacitor, the chart must be used to get a reasonable evaluation. This WAS briefly mentioned in the video, but only quickly in passing. - Semiconductor junction conduction in an in-circuit capacitor test is NOT the only thing that can totally invalidate ESR measurements. Parallel capacitance, or any more complex series/parallel stuff in the circuit can mess up the ESR readings. In-circuit ESR are very problematic and borderline unreliable. - ESR meters that test only at 100kHz are really intended to be only for aluminum electrolytics in switching power supply circuits, or other circuits where higher frequency signals are applied to the capacitor under test. 100kHz will give ESR readings that are likely to be pretty far off of the desired reading for capacitors used in audio circuits, linear power supply filtering, etc. So, the product being reviewed here is hardly a universal ESR tool, but its low price might fool novices into thinking it gives valid readings for capacitors in circuits they are more likely to be working with (unless all they are doing is repairing switching power supplies, looking for failed electrolytic). A problem with 'reviews' such as this one is that no comparison is given with reference tests made using ESR meters of known veracity. I have seen this particular meter 'reviewed' many times on CZcams, but the reviewer can't tell, in the tests shown, whether the device is producing reliable readings. I personally have tested one example of this product, comparing ESR readings with other (more expensive/professional/vetted) LCR meters (in their ESR modes), and found that the reading for small value aluminum electrolytics were fairly good, but one capacitance values got higher, the ESR reading this device gave were WAY off compared to more trustworthy testers. I can't be sure whether my one example was representative of the design, or if I had a bad example of the product.
I have one of these meters and I find it to be a good screening tool, but there can be significant differences at low ESR values between this tool and my Hantek 1833C. When the ESR is high, both my meters will show similar numbers. As long as you don't expect this instrument will give you "take it to the bank" ESR values, you will find it to be a handy tool on your bench.
I've used a DIY ESR meter (someone else's design I built years ago) for decades to fix stuff. With electrolytics, the ESR is either very low (below 1 ohm), or it's crazy high (> 10 or 20 ohms). You hardly ever find caps that are just a little bad. Therefor the precise value of the ESR isn't very useful. It's more of a "go no-go" gauge than a measurement tool. And once you find one bad or leaking cap, it's best to just replace them all anyway!
Fun to see you review this simple, but useful meter. Thanks! I've used one for a few years now for initial, cursory evaluation and it works very well. I fall back on the more capable ESR meters for testing at different frequencies when I want to learn more about a cap. Especially for big caps. Really enjoy being able to depend on your daily posts over morning coffee. Thanks so much for the continuously interesting topics. - jrh
The chemistry of electrolytics is not like a battery - the chemical soaks a paper to become conductive. That conductivity presses against both plates, and one end is "formed" using a current to make a thin oxide layer. This is what gives electrolytic capacitors their huge capacitance (capacitance is proportional to area and inversely proportional to thickness - the thin oxide layer giving you a very thin layer and high capacitance). When you connect the capacitor with the wrong polarity, the oxide layer dissolves and it shorts out as the chemicals boil and the capacitor pops (or explodes). When the capacitor gets old it dries out and thus it can't conduct electricity as well, so ESR goes up and since it can't make as good connection with the oxide layer, capacitance goes way down as the apparent thickness of the oxide layer grows due to bad connectivity.
I built an ESR meter from a schematic on someone's webpage like 25 years ago now, when there was only one ESR meter widely available, and was very expensive. I don't remember what frequency it runs at, but basically it's an AC ohm meter - it compares the signal going out to what comes back through the capacitor, and it runs a scavenged VU meter from a tape deck for the display. Basically when testing capacitors, they tend to have a small (acceptable) ESR, and anything that doesn't peg the analog meter at the 0 ohm end of the scale is bad. Like you showed in the video, the ESR tends to fail spectacularly. The exact value really isn't that important. It's either less than 1 ohm, or it's greater than 20ohm (which doesn't even move the needle). The only exception where "good" might be 1ohm or more is low value caps (10uf or 1uf) and or high voltage caps. But those aren't typically the ones you find failed either, or if they are, again they're failed big time, not just by a little. I use that meter a lot, and I think I've put 1 new 9V batteries in it since I built it. It's really efficient!
I have that for a few years now and it's saved me lots of times fixing stuff. When I open something up and it has electros I immediately get the esr meter and start replacing caps first and most of the time that fixes the problem. My unit has an older firmware though and it seems to run slow. Zeroing and getting readings are slower than yours. Only thing I didn't like is that it's not usb rechargeable so I put in a couple eneloops and added a resistor to the usb5v to battery + so it trickle charges if I plug it in when not in use.
Several bad capacitors in parallel with one good capacitor would still test good. The single good capacitor would have to carry all extreme transients and (depending on circumstance) might overheat and fail soon.
Measuring the capacitor in the circuit will work when it is connected via a diode. The diode in parallel did not change the value and I could also not realize any difference when it was turned around, (partly because the instrument was covered in the video, never mind). All together it is a good reminder what to take care of. I like the table, and I always prefer some extra voltage rating to improve the ESR value but I will also have to check why the resistor values are going up with higher voltage. So for instance for 100µF 25V is enough if it is just for ESR.
I might be totally wrong here, but when the ESR is the sum of the parallel and the series resistance, that would mean that a capacitor with 0.1Ohm ESR would leak like crazy. I always thought the ESR is just the "ohmic" part of the impedance (independent of the frequency, and thus simply the series resistance). Please note that I'm just a hobby-electronics guy.
It's not a simple sum. ESR is an AC measurement at a specified frequency. Leakage resistance is a DC measurement. There is a transformation that one can use at AC to treat a parallel reactance and resistance as an equivalent series reactance and resistance, or vice versa. If you apply that transformation to the leakage resistance, you can calculate its notional contribution to the equivalent series resistance. But it's all approximate. What's actually going on inside the capacitor includes all manner of electrical, thermal, mechanical, and magnetic effects. We bunch all of that up into two measurements, ESR and leakage, that are easy to make and that form useful approximations to what's really going on inside.
@@IMSAIGuyI know that the test is done using AC. That way the (ideal) capacitance becomes zero ohms. But I always thought that the parallel resistance really is just responsible for DC leakage current (like the leaky caps in all these old tube-radios), capacitance becomes reactance (Xc = 1/(omega*C)) , ESR is the resistance of the wires/plates/connections and the impedance is sqrt(ESR²+Xc²). I'm probably splitting hairs or I'm lost in translation ;)
@@agemans_stuff Like he said, ESR is basically an AC resistance check. The way the simple ESR meters work is the same way your DMM measures resistance, but they uses an ac signal rather than a dc signal. AC impedance of a capacitor is 1/jwc, so it depends on the capacitor value and the test frequency. You can think of a filter capacitor like a shunt that shunts the high frequency noise to ground through the capacitor, leaving nice clean DC on the other side. If there's resistance to the noise going through the capacitor to ground, it stays on the DC side of the capacitor causing issues.
ESR has nothing to do with isolation resistance (leakage), unless it is totally of range ( serial in range of ohms, isolation in range of mega ohms ). Would be nice to see test waveform on scope.
@@IMSAIGuy Probably some DSP-like calculations involved. People often underestimate cheap uC's like STM32f10x, which has 12 bit ADC/DAC and CPU faster than my first PC. Regards from Poland.
If it only has 100kHz test frequency than it is only good to test low impedance caps. The majority of (general purpose) caps are only 120Hz rated, no wonder if they will show high ESR @ 100kHz even brand new.
ESR = Equivalent Series Resistance or Effective Series Resistance? I have only heard people say "Equivalent" before, so Did you just say it wrong or is "Effective" right to? Or is "Equivalent" wrong and only "Effective" is right?
of course someone made the term ESR so there is a correct answer. the use of the English language is another topic. is something equivalent or effectively the same? does the ESR meter actually measure ESR or only something equivalent?
I think you are on point there.. An 1uF cap has 1.5 ohm impedance at 100Khz and thats probably measured in series with the real ESR so i wouldnt say that this meters only measures ESR, no.. They measure ESR with some error marginal with the leakage and all to.. I dont know, thats maybe a good topic for a video *winkwink* 🤣
@@MrDacorp don't overthink it much. Maybe it is worth to know that ESR is not always equal to cap impedance (frequency dependent), so I've heard numerous times, but haven't yet dedicated proper time to research myself, different story, maybe we can get a video on such topic too. "Equivalent" is a reference to parasitic characteristic in capacitor simulation model. Term "effective" is usually used when there is on one hand a nominal value or theoretical or etc, and on the other hand effective is something measured in a particular setup that is conditions dependent. But they are very close terms really. E.g. 10uF 25VDC ceramic cap has 10u nominal capacitance and at say at 10VDC bias is has only 4uF of effective capacitance.
For these in circuit testers you really don't have to worry about polarity. Electrolytic capacitors can be run at a half volt in reverse bias without damage or effect on the capacitance. So for these ESR testers that are in circuit using only 0.2 v test signal there really is no reason to pay attention to polarity.
He pointed out that the meter output is AC so polarity dosent matter with this instrument ? also the thing has headers to plug the cap directly in and bypass the leads if you wish, but you probably know that.@@IMSAIGuy
i have one of these but my ECR T7 meter is better and alot cheaper i also have a BSIDE ESR02 PRO that is better as well my experience is don't use the meter in circuit testing it will give you false readings.
All materials are made up of positive nuclei and negative electrons. Thus also are the dielectrics between capacitor plates. Insulators (dielectrics) use all of their electrons to form the chemical bonds that hold the material in its solid shape... they have no 'free' (mobile) electrons to conduct current The electric field (from a voltage = potential difference) stretches these atoms and bonds and stores more energy than vacuum. But, it is also impossible to make any substance 100% pure. Substantial effort and expense is needed to achieve 99.5% purity. Impurities in dielectrics (as well surface states at the dielectric's edges) usually offer mobile charges that can conduct some leakage current. The vacuum has no surface states at the edges, but there are no complete vacuums either -- yet our best vacuum is also our lowest leakage dielectric. Often dielectric materials (or the conducting liquid electrolyte that promotes a metal oxide insulation layer) dissipate energy as we stretch their bonds. Ions in an electrolyte move. Electret domains grow and shrink. Impurities move between material inclusions. Piezoelectricity changes the dielectric's shape, etc. Since these processes do not return all of the energy when the field is reduced, capacitors almost always have 'hysteresis losses.' Primarily, it is these hysteresis losses that cause equivalent series resistance (ESR). But the metal capacitor plates, wires, and wire bonds also have actual resistance that contribute to ESR.
chatgpt: A Leyden jar is a type of capacitor, but it has limitations and characteristics that make it different from an ideal capacitor. Here are some ways a Leyden jar is not a perfect capacitor: Dielectric Absorption: The dielectric material inside a Leyden jar (typically glass or plastic) can exhibit dielectric absorption, which means it can retain some charge even after being discharged, leading to a non-linear response. Leakage: Over time, a Leyden jar can lose its stored charge due to leakage currents through the dielectric material and the jar itself, which is not ideal for storing charge indefinitely. Parasitic Capacitance: The leads and the outer surface of a Leyden jar can create parasitic capacitance, which can affect its capacitance value and behavior. Non-Ideal Dielectric: The dielectric material in a Leyden jar is not a perfect insulator, so it has some conductivity, leading to energy loss and non-ideal behavior. Size and Shape: The shape and size of a Leyden jar can affect its capacitance value and distribution of electric field, making it less ideal for certain applications compared to a simple parallel plate capacitor. Frequency Dependence: The capacitance of a Leyden jar can vary with frequency due to factors like dielectric losses and parasitic capacitance, making its behavior frequency-dependent. Voltage Dependency: The capacitance of a Leyden jar can also vary with the applied voltage, especially at high voltages, which can affect its performance in certain applications. Non-Uniform Dielectric: In some cases, the dielectric material in a Leyden jar may not be uniformly distributed, leading to non-uniform electric field distribution and non-ideal behavior.
The only time you can't check a capacitor in circuit with an ESR meter is if there are multiple capacitors in parallel - any one good cap in parallel will show a low ESR even if the others are failed and are high ESR.
Just a few things I noticed in this video that seemed wrong, or which may have been over-simplified to the point of being misleading:
- ESR is only supposed to mean Equivalent Series Resistance, and it is a complex value incorporating a number of things about the capacitor internals. And, as stated, it is frequency dependent. However, in the usual models, it is meant to NOT include leakage, as that is parallel rather than series. So the sketch of a resistor in parallel with the ideal capacitor could be considered to be misleading or confusing.
- The equivalent parallel resistance (across the ideal capacitor) should have infinite resistance, so a DCR reading should be a high Ohms value. ESR values should be very low, less than an Ohm for most electrolytic capacitors. High ESR values in an aluminum electrolytic are typically due to drying out and/or breakdown of the dielectric, while low DCR values are typically due to failure of the internal metallic structure of the cap.
- Better ESR (or LCR) meters have separate ESR and DCR (DC resistance) modes, and in DCR mode they are testing for that leakage. Indeed, some LSR meters that test DCR will do that test first, and only proceed to testing ESR if the DCR measurement is OK. This is because even a very leaky (fails the DCR test) capacitor might still pass an ESR test.
- With this model of tester, is is probably best to always use the printed ESR chart, since the go/no-go message on the LCD screen is ONLY for aluminum electrolytic capacitors rated for about 25V. Testing any other kind or voltage of capacitor, the chart must be used to get a reasonable evaluation. This WAS briefly mentioned in the video, but only quickly in passing.
- Semiconductor junction conduction in an in-circuit capacitor test is NOT the only thing that can totally invalidate ESR measurements. Parallel capacitance, or any more complex series/parallel stuff in the circuit can mess up the ESR readings. In-circuit ESR are very problematic and borderline unreliable.
- ESR meters that test only at 100kHz are really intended to be only for aluminum electrolytics in switching power supply circuits, or other circuits where higher frequency signals are applied to the capacitor under test. 100kHz will give ESR readings that are likely to be pretty far off of the desired reading for capacitors used in audio circuits, linear power supply filtering, etc. So, the product being reviewed here is hardly a universal ESR tool, but its low price might fool novices into thinking it gives valid readings for capacitors in circuits they are more likely to be working with (unless all they are doing is repairing switching power supplies, looking for failed electrolytic).
A problem with 'reviews' such as this one is that no comparison is given with reference tests made using ESR meters of known veracity. I have seen this particular meter 'reviewed' many times on CZcams, but the reviewer can't tell, in the tests shown, whether the device is producing reliable readings. I personally have tested one example of this product, comparing ESR readings with other (more expensive/professional/vetted) LCR meters (in their ESR modes), and found that the reading for small value aluminum electrolytics were fairly good, but one capacitance values got higher, the ESR reading this device gave were WAY off compared to more trustworthy testers. I can't be sure whether my one example was representative of the design, or if I had a bad example of the product.
I have one of these meters and I find it to be a good screening tool, but there can be significant differences at low ESR values between this tool and my Hantek 1833C. When the ESR is high, both my meters will show similar numbers. As long as you don't expect this instrument will give you "take it to the bank" ESR values, you will find it to be a handy tool on your bench.
I've used a DIY ESR meter (someone else's design I built years ago) for decades to fix stuff. With electrolytics, the ESR is either very low (below 1 ohm), or it's crazy high (> 10 or 20 ohms). You hardly ever find caps that are just a little bad. Therefor the precise value of the ESR isn't very useful. It's more of a "go no-go" gauge than a measurement tool. And once you find one bad or leaking cap, it's best to just replace them all anyway!
Fun to see you review this simple, but useful meter. Thanks! I've used one for a few years now for initial, cursory evaluation and it works very well. I fall back on the more capable ESR meters for testing at different frequencies when I want to learn more about a cap. Especially for big caps. Really enjoy being able to depend on your daily posts over morning coffee. Thanks so much for the continuously interesting topics. - jrh
The chemistry of electrolytics is not like a battery - the chemical soaks a paper to become conductive. That conductivity presses against both plates, and one end is "formed" using a current to make a thin oxide layer. This is what gives electrolytic capacitors their huge capacitance (capacitance is proportional to area and inversely proportional to thickness - the thin oxide layer giving you a very thin layer and high capacitance). When you connect the capacitor with the wrong polarity, the oxide layer dissolves and it shorts out as the chemicals boil and the capacitor pops (or explodes). When the capacitor gets old it dries out and thus it can't conduct electricity as well, so ESR goes up and since it can't make as good connection with the oxide layer, capacitance goes way down as the apparent thickness of the oxide layer grows due to bad connectivity.
You know what viewers crave, so open it up for a look.
czcams.com/video/JxSiQOLJJ8k/video.html
I bought one of these years ago and forgot how to use it. Thank you, very informative.
I built an ESR meter from a schematic on someone's webpage like 25 years ago now, when there was only one ESR meter widely available, and was very expensive. I don't remember what frequency it runs at, but basically it's an AC ohm meter - it compares the signal going out to what comes back through the capacitor, and it runs a scavenged VU meter from a tape deck for the display. Basically when testing capacitors, they tend to have a small (acceptable) ESR, and anything that doesn't peg the analog meter at the 0 ohm end of the scale is bad. Like you showed in the video, the ESR tends to fail spectacularly. The exact value really isn't that important. It's either less than 1 ohm, or it's greater than 20ohm (which doesn't even move the needle). The only exception where "good" might be 1ohm or more is low value caps (10uf or 1uf) and or high voltage caps. But those aren't typically the ones you find failed either, or if they are, again they're failed big time, not just by a little. I use that meter a lot, and I think I've put 1 new 9V batteries in it since I built it. It's really efficient!
I have that for a few years now and it's saved me lots of times fixing stuff. When I open something up and it has electros I immediately get the esr meter and start replacing caps first and most of the time that fixes the problem. My unit has an older firmware though and it seems to run slow. Zeroing and getting readings are slower than yours. Only thing I didn't like is that it's not usb rechargeable so I put in a couple eneloops and added a resistor to the usb5v to battery + so it trickle charges if I plug it in when not in use.
I have a Blue ESR kit I haven't built over 15 years! But my Halli boat anchors still perform. (I know......)
Several bad capacitors in parallel with one good capacitor would still test good. The single good capacitor would have to carry all extreme transients and (depending on circumstance) might overheat and fail soon.
I have one and it;s become a very useful tool in the work shop, I like it.
Measuring the capacitor in the circuit will work when it is connected via a diode. The diode in parallel did not change the value and I could also not realize any difference when it was turned around, (partly because the instrument was covered in the video, never mind).
All together it is a good reminder what to take care of. I like the table, and I always prefer some extra voltage rating to improve the ESR value but I will also have to check why the resistor values are going up with higher voltage. So for instance for 100µF 25V is enough if it is just for ESR.
I have one from few years. Very usefull.
Good video, but I think you should discharge the electrolytic cap first before the test, especially the big one
thank you very well explained
I might be totally wrong here, but when the ESR is the sum of the parallel and the series resistance, that would mean that a capacitor with 0.1Ohm ESR would leak like crazy. I always thought the ESR is just the "ohmic" part of the impedance (independent of the frequency, and thus simply the series resistance). Please note that I'm just a hobby-electronics guy.
the test is done at 100kHz AC. at DC there is no leakage. the capacitor passes AC
It's not a simple sum. ESR is an AC measurement at a specified frequency. Leakage resistance is a DC measurement. There is a transformation that one can use at AC to treat a parallel reactance and resistance as an equivalent series reactance and resistance, or vice versa. If you apply that transformation to the leakage resistance, you can calculate its notional contribution to the equivalent series resistance. But it's all approximate. What's actually going on inside the capacitor includes all manner of electrical, thermal, mechanical, and magnetic effects. We bunch all of that up into two measurements, ESR and leakage, that are easy to make and that form useful approximations to what's really going on inside.
@@IMSAIGuyI know that the test is done using AC. That way the (ideal) capacitance becomes zero ohms. But I always thought that the parallel resistance really is just responsible for DC leakage current (like the leaky caps in all these old tube-radios), capacitance becomes reactance (Xc = 1/(omega*C)) , ESR is the resistance of the wires/plates/connections and the impedance is sqrt(ESR²+Xc²). I'm probably splitting hairs or I'm lost in translation ;)
@@agemans_stuff there is both parallel and series resistance and they act different vs frequency and voltage. and that is over simplified.
@@agemans_stuff Like he said, ESR is basically an AC resistance check. The way the simple ESR meters work is the same way your DMM measures resistance, but they uses an ac signal rather than a dc signal. AC impedance of a capacitor is 1/jwc, so it depends on the capacitor value and the test frequency. You can think of a filter capacitor like a shunt that shunts the high frequency noise to ground through the capacitor, leaving nice clean DC on the other side. If there's resistance to the noise going through the capacitor to ground, it stays on the DC side of the capacitor causing issues.
ESR has nothing to do with isolation resistance (leakage), unless it is totally of range ( serial in range of ohms, isolation in range of mega ohms ). Would be nice to see test waveform on scope.
it looked like a rounded square wave. not sine.
@@IMSAIGuy Probably some DSP-like calculations involved. People often underestimate cheap uC's like STM32f10x, which has 12 bit ADC/DAC and CPU faster than my first PC. Regards from Poland.
Testing in circuit has an issue when their are caps in parallel. You might be measuring multiple caps in parallel..
Great video! Thanks! Are in circuit tests with your nice LCR meter more accurate than the MESR-100?
out of circuit the LCR is more accurate. for quick testing (especially in-circuit) who cares
Usually at higher frequencies in circuit measurement is typically better iirc
You need to have a video featuring Imsai dog. He is a cutie !!!
he's been in a couple
czcams.com/video/NEr2osFrrVc/video.htmlsi=F0dFciPlOh9IBisc
czcams.com/video/GRcRzVszo80/video.htmlsi=e4TvsCLmQWmSxG0S
I would have liked to see you testing the last off board bad capacitor with a ohmmeter. Should you get the same resistance reading as the ESR meter?
maybe, ESR meter measures with AC signal, ohmmeter measures with DC signal
I have a question about joining by Patreon. I want to contribute, but I don't want monthly payments. How can I do that?
you can't. just do a month and then pause
If it only has 100kHz test frequency than it is only good to test low impedance caps.
The majority of (general purpose) caps are only 120Hz rated, no wonder if they will show high ESR @ 100kHz even brand new.
I recently bought one of these and the battery is draining overnight,anyone any ideas why?
ESR = Equivalent Series Resistance or Effective Series Resistance? I have only heard people say "Equivalent" before, so Did you just say it wrong or is "Effective" right to? Or is "Equivalent" wrong and only "Effective" is right?
of course someone made the term ESR so there is a correct answer. the use of the English language is another topic. is something equivalent or effectively the same? does the ESR meter actually measure ESR or only something equivalent?
I think you are on point there.. An 1uF cap has 1.5 ohm impedance at 100Khz and thats probably measured in series with the real ESR so i wouldnt say that this meters only measures ESR, no.. They measure ESR with some error marginal with the leakage and all to.. I dont know, thats maybe a good topic for a video *winkwink* 🤣
@@MrDacorp don't overthink it much. Maybe it is worth to know that ESR is not always equal to cap impedance (frequency dependent), so I've heard numerous times, but haven't yet dedicated proper time to research myself, different story, maybe we can get a video on such topic too.
"Equivalent" is a reference to parasitic characteristic in capacitor simulation model. Term "effective" is usually used when there is on one hand a nominal value or theoretical or etc, and on the other hand effective is something measured in a particular setup that is conditions dependent. But they are very close terms really.
E.g. 10uF 25VDC ceramic cap has 10u nominal capacitance and at say at 10VDC bias is has only 4uF of effective capacitance.
For these in circuit testers you really don't have to worry about polarity. Electrolytic capacitors can be run at a half volt in reverse bias without damage or effect on the capacitance. So for these ESR testers that are in circuit using only 0.2 v test signal there really is no reason to pay attention to polarity.
Curious how it compares in resistance accuracy to the nicer meter. Or to a bench cap test?
Post a teardown please 😊
czcams.com/video/JxSiQOLJJ8k/video.htmlsi=dNABZtpZUb_SCC-z
@@IMSAIGuy thank you very much but your explanation is much more preferred
He pointed out that the meter output is AC so polarity dosent matter with this instrument ? also the thing has headers to plug the cap directly in and bypass the leads if you wish, but you probably know that.@@IMSAIGuy
i have one of these but my ECR T7 meter is better and alot cheaper i also have a BSIDE ESR02 PRO that is better as well my experience is don't use the meter in circuit testing it will give you false readings.
All materials are made up of positive nuclei and negative electrons. Thus also are the dielectrics between capacitor plates. Insulators (dielectrics) use all of their electrons to form the chemical bonds that hold the material in its solid shape... they have no 'free' (mobile) electrons to conduct current The electric field (from a voltage = potential difference) stretches these atoms and bonds and stores more energy than vacuum. But, it is also impossible to make any substance 100% pure. Substantial effort and expense is needed to achieve 99.5% purity. Impurities in dielectrics (as well surface states at the dielectric's edges) usually offer mobile charges that can conduct some leakage current. The vacuum has no surface states at the edges, but there are no complete vacuums either -- yet our best vacuum is also our lowest leakage dielectric.
Often dielectric materials (or the conducting liquid electrolyte that promotes a metal oxide insulation layer) dissipate energy as we stretch their bonds. Ions in an electrolyte move. Electret domains grow and shrink. Impurities move between material inclusions. Piezoelectricity changes the dielectric's shape, etc. Since these processes do not return all of the energy when the field is reduced, capacitors almost always have 'hysteresis losses.' Primarily, it is these hysteresis losses that cause equivalent series resistance (ESR). But the metal capacitor plates, wires, and wire bonds also have actual resistance that contribute to ESR.
2:17 what about a leyden jar?
pretty good, but no one is perfect
chatgpt:
A Leyden jar is a type of capacitor, but it has limitations and characteristics that make it different from an ideal capacitor. Here are some ways a Leyden jar is not a perfect capacitor:
Dielectric Absorption: The dielectric material inside a Leyden jar (typically glass or plastic) can exhibit dielectric absorption, which means it can retain some charge even after being discharged, leading to a non-linear response.
Leakage: Over time, a Leyden jar can lose its stored charge due to leakage currents through the dielectric material and the jar itself, which is not ideal for storing charge indefinitely.
Parasitic Capacitance: The leads and the outer surface of a Leyden jar can create parasitic capacitance, which can affect its capacitance value and behavior.
Non-Ideal Dielectric: The dielectric material in a Leyden jar is not a perfect insulator, so it has some conductivity, leading to energy loss and non-ideal behavior.
Size and Shape: The shape and size of a Leyden jar can affect its capacitance value and distribution of electric field, making it less ideal for certain applications compared to a simple parallel plate capacitor.
Frequency Dependence: The capacitance of a Leyden jar can vary with frequency due to factors like dielectric losses and parasitic capacitance, making its behavior frequency-dependent.
Voltage Dependency: The capacitance of a Leyden jar can also vary with the applied voltage, especially at high voltages, which can affect its performance in certain applications.
Non-Uniform Dielectric: In some cases, the dielectric material in a Leyden jar may not be uniformly distributed, leading to non-uniform electric field distribution and non-ideal behavior.
@@IMSAIGuy if I recall correctly... You can take the electrodes away and reassemble them and still get a shock
I
Knowledgeable enough to explain how the meter works but draws the current lagging in a capacitor!? haha Just poking fun.
ELI the ICE man 🙃
You can't test capicitors in circuit.
I just did. found a bad cap. depends on your idea of 'test'
You can... Just not accurately.
The only time you can't check a capacitor in circuit with an ESR meter is if there are multiple capacitors in parallel - any one good cap in parallel will show a low ESR even if the others are failed and are high ESR.