Homemade DC/AC Oscilloscope Current Clamp | Hall Sensor + Ferrite Core

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  • เผยแพร่เมื่อ 4 มิ.ย. 2024
  • 🔥The clamp works perfect but is not the most professional tool ever, it is more as an example in order to understand the theory. You could always improve it using better OP AMP and a better circuit. It could observe both DC and AC currents with a range up to 9A. I hole you like it.
    🔀LINKS
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    AC clamp: www.electronoobs.com/eng_circu...
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    Arduino multimeter video: • Arduino based current ...
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    00:00 Intro
    00:33 How to measure Current
    04:07 Probe Teardown
    07:20 DC current probe
    09:55 Homemade Probe
    12:47 Schematic
    13:08 Calibration
    15:25 Thank you
    Like share and subscribe to motivate me. Thank you
    #current
    #clamp
    #homemade
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ความคิดเห็น • 137

  • @ELECTRONOOBS
    @ELECTRONOOBS  6 ปีที่แล้ว +25

    I hope that you'll enjoy this video. If you have any question or maybe a improvement just live it in the comment section here. Visit my webpage for more. Also, visit my Pateron site if you would like to help me. Thank you.

    • @UndernetSystems
      @UndernetSystems 6 ปีที่แล้ว

      Gracias hermano, hermoso video!

    • @thecombatengineer7069
      @thecombatengineer7069 5 ปีที่แล้ว +2

      I would suggest that anyone who builds this makes sure that get a LINEAR OUTPUT Hall Effect Sensor. Something like the A3114 Hall Effect is a fast-switch and only goes high or low, so it wouldn’t work for measuring linear increases. I tired it and failed. No worries, I’ll get some SS49E or similar Linear Output Sensors. Great job and thanks brotha!

  • @sincerelyyours7538
    @sincerelyyours7538 6 ปีที่แล้ว +14

    I was looking for a current probe like this not long ago but gave up due to the high prices. This one is quite possibly the ugliest looking probe I've ever seen, but that's OK because it obviously works! Why should I buy a probe costing hundreds of dollars when I can now easily build my own for dirt cheap? I learned something today. Great job, and I look forward to seeing more from you!

  • @anthonycalia1317
    @anthonycalia1317 6 ปีที่แล้ว +5

    Excellent video. Your ability to explain the concepts and circuits was exceptional. I hope to see more of your work.

  • @qps9380
    @qps9380 6 ปีที่แล้ว +3

    So good man! I've always wondered how the current clamps worked!

  • @jimwyt
    @jimwyt 4 ปีที่แล้ว

    What a wonderful, creative, low cost hack! This is exactly the basis I needed for a non-invasive high current monitor for a battery back up sump pump. Thanks so much for sharing!

  • @SteinErikDahle
    @SteinErikDahle 6 ปีที่แล้ว +14

    Awesome video! I actually learnt something new today about DC-clamps!
    Thanks!

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว +2

      U wellcome, I'm glad to hear!

  • @robotronix-co-il
    @robotronix-co-il 5 ปีที่แล้ว +3

    Tank you for the Excellent video , you just save me few days of experiments in the lab

  • @agaelema
    @agaelema 6 ปีที่แล้ว +3

    Awesome project! I Will follow this video and mount my own diy current probe . Thanks for share

  • @ryanshelton4545
    @ryanshelton4545 4 ปีที่แล้ว +2

    I loved this video. Thank you for sharing, you're a great teacher.

  • @danielolmo9625
    @danielolmo9625 6 ปีที่แล้ว +1

    Nice video! It's been a while since I've been looking for this!

  • @lonniebates1533
    @lonniebates1533 4 ปีที่แล้ว

    Best explanation I've seen of a dc current probe.

  • @MrRonychakraborty
    @MrRonychakraborty 6 ปีที่แล้ว

    You are the Boss. You saved my time a lot thanks.

  • @Seshagopalan967
    @Seshagopalan967 6 ปีที่แล้ว +2

    Once again, you made my day!

  •  6 ปีที่แล้ว

    Excellent video! Thanks for explanation!
    I have a Unit 201E and i will try to modify it to add a analog output. Many thanks!

  • @AB-yu2tj
    @AB-yu2tj 4 ปีที่แล้ว

    It's good short and to the point. Thank you

  • @brujo_millonario
    @brujo_millonario 5 ปีที่แล้ว +1

    Thank you, I've learned a lot.

  • @elson2k
    @elson2k 3 ปีที่แล้ว

    Nice video ;) I was just searching for an easy way to measure and observe currents via oscilloscope and your solution gave me some ideas. Thanks! :)

  • @WaltonPete
    @WaltonPete 6 ปีที่แล้ว +4

    Excellent video!
    Love the project idea - some AC scope clamps can cost as much as a budget DSO!
    Great explanation and implementation of cheap, easy to source parts.

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว

      Pete Allum thank you very much! Keep up!

  • @hebrewhammer1000
    @hebrewhammer1000 5 ปีที่แล้ว +2

    Thank you for sharing. Great video.

  • @charvakkarpe
    @charvakkarpe 4 ปีที่แล้ว +2

    Wow, one of the best technical videos I've seen on TH-cam. You clearly have a solid understanding of physics and electronics, cover content at the right pace, include the right video shots and animations. I liked the B-field overlay on the magnetic core, with the X showing current flowing down and the arrows spinning clockwise.
    I'd love a follow-up video with details on the Hall effect, and a demonstration of what happens if you move the wire around within the ring. I suspect something like Gauss's law says it doesn't matter where the current is inside the ring, but clarification would be great. I'm about to go look it up for myself.

    • @charvakkarpe
      @charvakkarpe 4 ปีที่แล้ว

      Found it. It's called Ampere's Circuital Law. The line integral of B-field along a loop is proportional to the current it encloses. I had pictured an entire array of Hall-effect sensors inside one of those current clamps, but using a ferrite core to capture the field and force it through a single Hall-effect sensor makes sense. en.wikipedia.org/wiki/Amp%C3%A8re%27s_circuital_law#Explanation

  • @artiomoable
    @artiomoable 2 ปีที่แล้ว +1

    Thanks. good video! What max AC frequency it can measure?

  • @warshatube
    @warshatube 6 ปีที่แล้ว +1

    thank you so much sir, I have question if I make the DC amp clamp without the amplifier can it measure high DC current (300-400 amp)

  • @sylvainlazare1114
    @sylvainlazare1114 6 ปีที่แล้ว +1

    Thank you! I hear for the first time the principle of DC clamp probe. My question is how sensitive is it ? commercial clamp probes are sensitive to

  • @bigt121947
    @bigt121947 6 ปีที่แล้ว

    thank you for your time.

  • @lupoal4113
    @lupoal4113 9 หลายเดือนก่อน

    bravo! very useful video!
    about the "better" op-amp... do you have any suggestion?

  • @polkijain97
    @polkijain97 4 ปีที่แล้ว

    Hi. Great explanation of the amp clamp. Can you point to any off-the-shelf component to integrate into the circuit that can measure 10A to 150A linearly and give millivolts as output to be read through an Arduino or any other microcontroller?

  • @Taran72
    @Taran72 4 ปีที่แล้ว +1

    This project is really awesome and yes, I've found out what to do with a bunch of half ferrite cores I got :) . I think that the improvements can be made with the amplifier circuit and the calibration...but you speak of the AD623 in your video on current sensors....can I use the AD623 for all these type of projects related to probes or instrumentation circuits? I'm not that familiar with OPamps.

  • @FreeCircuitLab
    @FreeCircuitLab ปีที่แล้ว +1

    Nice video brother!
    You should regulate the supply voltage because the output of the sensor depends on the supply. And also you have to use two potentiometers, one for zero adjust, another for calibration. Zero adjust is needed because the sensor outputs half of the supply voltage at zero field. We have to get rid of that first

  • @sereenasonya
    @sereenasonya ปีที่แล้ว

    Well done Brother. Loved it.

  • @georgedsuarez
    @georgedsuarez 6 ปีที่แล้ว

    Excellent video!

  • @wgm-en2gx
    @wgm-en2gx 6 ปีที่แล้ว +1

    Nice explanation. thanks.

  • @JAKOB1977
    @JAKOB1977 5 ปีที่แล้ว +3

    "You know nothing John Snow". (thats how i feel when watching some of these aspects in this video.. yeah my mindset is pretty limied when it comes to electronics but I do like my current AC&DC clamp meter 210E.
    Im such a noob I actually thought these big clamp meters was for batteries and often was puzzled why they didn't open up wider and was supprised when i finally realized you could measure current without toggling physically onto the circuit..)
    thx for the vid.

  • @lalmuanpuiamizo
    @lalmuanpuiamizo 6 ปีที่แล้ว +1

    Nicely done

  • @eletronicaautomotivadicass5520
    @eletronicaautomotivadicass5520 3 ปีที่แล้ว

    Ótimo vídeo. . esse projeto substitui todas as funções do cc65? Posso usar no ramo automotivo?

  • @johnconrad5487
    @johnconrad5487 6 ปีที่แล้ว

    i enjoyed the video. the frequency response is very low. did you try to speed it up in any way? perhaps by adding a small cap... maye 100 pF across the input 1K resistor. it may help

  • @zikermu
    @zikermu 3 ปีที่แล้ว

    Thanks a lot for this great educationnal video .

  • @ednja
    @ednja 3 ปีที่แล้ว +2

    Can this clamp be plugged into a multimeter instead of an oscilloscope? What is the maximum DC current it can be used to measure?

  • @satviksharma3722
    @satviksharma3722 3 ปีที่แล้ว

    This was a great video!!

  • @apurvakalvade2301
    @apurvakalvade2301 5 ปีที่แล้ว

    In case if we don't want to use BNC connector and want the reading on the LCD _ then if we directly connect the output of the OPAMP to the LCD, will we able to get the display of current ratings on LCD?

  • @Slic-Rock
    @Slic-Rock 5 ปีที่แล้ว

    Hi nice video, what current clamp can you recommend for Fluke unit. Their clamp are expensive and have for 1mV DC = 1Amp DC and 1mV AC = 1Amp AC.
    I would like to find affordable clamps for Fluke 124. Thank you

  • @FyaaahS
    @FyaaahS 6 ปีที่แล้ว

    Awesome video!!

  • @lenaroseguera1241
    @lenaroseguera1241 6 ปีที่แล้ว +2

    I read that the maximum supply voltage for the 49e sensor is 6.5v. how can you supply it with 9v?

  • @crtsuznik
    @crtsuznik 5 ปีที่แล้ว +7

    I'm surprised you didn't burn the sensor. The datasheet says it's operating voltage is between 3.0 and 6.5V

  • @jezzapimp
    @jezzapimp 4 ปีที่แล้ว

    Awsome project! What sort of bandwidth do you get with this unit?

  • @vysakhav
    @vysakhav 6 ปีที่แล้ว

    Thanks ,very helpful

  • @kac3514
    @kac3514 4 ปีที่แล้ว +2

    Can this work with multimeters that have this function

  • @next8226
    @next8226 6 ปีที่แล้ว +3

    Love ❤️ your all videos you grate😍😍😍😍😍😍😍😍😍

  • @kostaslaza12
    @kostaslaza12 6 ปีที่แล้ว

    awesome keep going!!

  • @viekynajoan1520
    @viekynajoan1520 4 ปีที่แล้ว

    Any recommended hall eff. sensor ?
    Thank you in advance 🙏🏻

  • @mojtabajamal3457
    @mojtabajamal3457 4 ปีที่แล้ว

    very nice ...thank you

  • @asmarahman9291
    @asmarahman9291 4 ปีที่แล้ว

    Hello I'm student from University Putra Malaysia from Malaysia. May I ask, for DC Current Clamp Meter, is it just hall effect ic and ferrite core only or u need copper coil around the ferrite core?

  • @qzorn4440
    @qzorn4440 ปีที่แล้ว

    A most excellent current clamp circuit. Do you have any suggestions on an clamp-on current circuit on a 2,300 volt AC wire? 😎 Thank you.

  • @alfredseaman2796
    @alfredseaman2796 5 ปีที่แล้ว

    Thank you so much

  • @tiagonet8794
    @tiagonet8794 2 ปีที่แล้ว

    what modification will you have to make for measure 1000A or 5000A?

  • @chuckthom7012
    @chuckthom7012 5 ปีที่แล้ว

    What do you think about using a clamp off an old timing light?

  • @yoramstein
    @yoramstein 6 ปีที่แล้ว

    Hello mr.Electronoobs great videos you make. Just wanted to ask what 3D printer did you use to make the case for this probe?

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว

      In that time of the Year I was using my Anet A8. Keep up!

  • @waqaszahid86
    @waqaszahid86 5 ปีที่แล้ว

    I am in the middle of building something similar but it is exclusively for measuring AC currents, I am using a self made current transformer with two pair of windings, after building the amplifier circuit and extracting the RMS value in a manner similar to what a non true RMS DMM does I have realized that the self made transformer with toroid core from atx power supply is very non linear and i am still struggling to find a method to resolve this problem.

  • @janoschlolmann8822
    @janoschlolmann8822 6 ปีที่แล้ว +4

    Very nice video, but there is still one Question: You said that the LM324 is a bad operational amplifier, why dou you think like that and which one would you recommend ??

    • @johnconrad5487
      @johnconrad5487 6 ปีที่แล้ว +1

      there are many op amps that are much faster... the LM324 is old and slow.

    • @loulounet777
      @loulounet777 6 ปีที่แล้ว +4

      LM324 is basically four LM741. and we all know the 741 is an old thing. amazing at the time but way passed and very very slow. a better "general purpose" opamp nowadays would be the TL071 from texas :) very cheap :)

  • @ihabhamad8290
    @ihabhamad8290 6 ปีที่แล้ว

    you are a perfect man :)

  • @garethronaldo8692
    @garethronaldo8692 6 ปีที่แล้ว +3

    Nice

  • @ronniepirtlejr2606
    @ronniepirtlejr2606 4 ปีที่แล้ว +1

    When measuring DC, could it be possible to design a circuit and not use a hall sensor? Maybe something that pulses AC (low voltage of course!) Then design a small circuit that can calculate the difference in current/ resistance in dc?
    I'm really new to electronics I'm trying to learn schematics, chips & components Etc. I realize the hall sensor is pretty simple. I just want to know if it's possible?

  • @devilvortex1
    @devilvortex1 4 ปีที่แล้ว

    can I calibrate the clamp 1A and set the output to 0.1v?

  • @UpcycleElectronics
    @UpcycleElectronics 6 ปีที่แล้ว

    4:53 ...is not a transformer in the classical sense. It's a choke used to reduce/filter back emf noise from the device and prevent it from returning to the mains line ;)

  • @borisivanov1175
    @borisivanov1175 4 ปีที่แล้ว +1

    What if I need to measure 2000-3000amps? How different it make such device?

  • @itsmekennyd
    @itsmekennyd 2 ปีที่แล้ว

    thanks I really need to make 2000 amp one could you help?

  • @sayantanmaiti2513
    @sayantanmaiti2513 6 ปีที่แล้ว

    Sir can you please explain a little bit why did you used that potentiometer with the opamp and why you preferred the inverting configuration of opamp?

    • @sonyobright2106
      @sonyobright2106 5 ปีที่แล้ว

      the 49e hall sensor has a bias voltage of half the power vcc ... means that the hall sensor would output a 2.5 v for a vcc= 5v with NO magnetic field sensed by the sensor ... the potentiometre help to offset that bias voltage ...the inverted configuration help for the gain. in this case 100. witch is too big in my opinion .. a gain of 10 will be more than enough.. another strange thing is the 9v battery that is too big for the sensor. in the end the filter is wrong and not suitable for this ...good work

  • @ikkeslim007
    @ikkeslim007 6 ปีที่แล้ว +1

    Is there a way to make it usable to measure currents up to 70-80 amps or more? Maybe with a switch for high/low amp range? I'm really interested in making one, but i would like to measure more than 9amps! It's an relative easy to understand schematic, really love it!

    • @CheapskateGarage
      @CheapskateGarage 2 ปีที่แล้ว +2

      He's using an amplifier to bump the sensitivity up to 1V/A. You need yours to be less sensitive. You could scale the gain down to ten (he used a gain of 100). Or, you could leave out the amp and see where that gets you. Experiment measuring a known current and see what your sensitivity is.

  • @hannnnn310
    @hannnnn310 6 ปีที่แล้ว +3

    Hi!
    May i ask?...How high is the max frequency of the current clamp could measure?

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว

      Hi there. Can't remember for sure. The max freq is given by the max freq of the OPAMP and the Hall sensor. Just check those datasheets. Sorry.
      Keep up!

  • @mohammadqz8956
    @mohammadqz8956 4 ปีที่แล้ว

    can I make one with an accuracy of 1mili-amps like this?

  • @maurizioghizzani5734
    @maurizioghizzani5734 6 ปีที่แล้ว +1

    If i change the coil size does the sensitivity change? What op can be used to improve the precision ? Thank

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว +1

      To improve the amplified signal you could use the same OPAM but in a chain connection, the output from the first OPAM to the input of the second but with smaller scales.

  • @morbitalok
    @morbitalok 6 ปีที่แล้ว

    how to easly adopt to 40 mV/A ? anyway great thng and movie!

  • @anukeshambatkar6255
    @anukeshambatkar6255 4 ปีที่แล้ว

    Sir can you please make a tutorial on wcs1500 current sensor which is of 200A capacity

  • @johnopfer8065
    @johnopfer8065 4 ปีที่แล้ว

    What is part number of Hall sensor you used?

  • @DavidLeeMenefee
    @DavidLeeMenefee 6 ปีที่แล้ว +1

    Nice video. Thumbs up...PEACE

    • @SianaGearz
      @SianaGearz 6 ปีที่แล้ว

      Small planet, eh?

  • @ghamor7590
    @ghamor7590 6 ปีที่แล้ว +1

    thank you very mach

  • @joycepark6299
    @joycepark6299 4 ปีที่แล้ว

    Hi LM324 is currently not available in our area so we used LM358 but the result is kinda sketchy. Can you recommend to us other IC to ampli the result? Thank you.

    • @joycepark6299
      @joycepark6299 4 ปีที่แล้ว

      and also when we try it we got a result of 0.025-0.033 V (without conductor on the magnet) and
      0.099-0.106 Voltage (with conductor). Then on our second test we got different result, does the circuit really had approximately 0.025V ? Thank ypi for answering it will be a great help in our project.

  • @MrBreak745
    @MrBreak745 6 ปีที่แล้ว +1

    can you make BMS circuit for 3 li-ion battery pack > it would be a great video

  • @yashrewalia2116
    @yashrewalia2116 4 ปีที่แล้ว

    Can you give the calculation related to the circuit for DC clamp

  • @gastarbieter
    @gastarbieter 6 ปีที่แล้ว

    what is your opinion about the hantek current clamp?

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว

      It's a decent one. I don't use clamps too much. The good thing is that it is quite low price.

  • @Tirdad1981
    @Tirdad1981 5 ปีที่แล้ว

    I built this but it can only measure DC currents. I can see no changes in hall sensor output voltage with AC.

  • @antontaranov533
    @antontaranov533 6 ปีที่แล้ว

    отличное видео. С меня лайк

  • @thelasttimeitried
    @thelasttimeitried 5 ปีที่แล้ว +1

    Really great video. Thanks for taking the time to create the project and explain it so thoroughly. By way of improvement, the letter 'u' in the word 'circuit' is not pronounced. Your English is great!

  • @0dium.
    @0dium. 4 ปีที่แล้ว

    HAL sensors are great components

  • @gunjankumar-fr8lv
    @gunjankumar-fr8lv 4 ปีที่แล้ว

    How to remove magnetic field around wire so that the clamp meter can not read the current ?

  • @MCsCreations
    @MCsCreations 6 ปีที่แล้ว +4

    Really nice! Liked specifically the ugly tooth you put in it (at 14:07), looks an angry animal. LOL

  • @mihapeterle204
    @mihapeterle204 5 ปีที่แล้ว

    Why inverying amp and not noninverting?

  • @MrHD71
    @MrHD71 6 ปีที่แล้ว +1

    what is the better amplifier that you're waiting on?

    • @ELECTRONOOBS
      @ELECTRONOOBS  6 ปีที่แล้ว +1

      LM358

    • @SianaGearz
      @SianaGearz 6 ปีที่แล้ว +1

      Waaait. LM358 and LM324 are the same thing! Different packaging, different number of units per package, but same units inside. You can even use the extra units of LM324 to increase either noise and distortion suppression or current handling capability.

    • @sincerelyyours7538
      @sincerelyyours7538 6 ปีที่แล้ว

      Can you show us how?

  • @nikgru4577
    @nikgru4577 5 ปีที่แล้ว

    I have the Same Multimeter

  • @genuino-qo5yq
    @genuino-qo5yq 6 ปีที่แล้ว +1

    Pls make an arduino based switching power supply

  • @FriendlySuslik
    @FriendlySuslik 6 ปีที่แล้ว +2

    no se para que sirve pero lo quiero, y lo quiero ya

  • @peterdkay
    @peterdkay 6 ปีที่แล้ว +1

    Great explanation, however I think schematic is wrong. You show a 9M/10pF in series with scope connector. As scopes have a 1M input impedance this filter has a 10:1 attenuation so maximum voltage at scope is 0.9V not 9V.
    I would like to see frequency response:
    You measure rise time of clamp by generating a 100mA current pulse at 1kHz.
    Easy to do using a 100 ohm resistor in emitter of transistor and drive base with 0 to 1.5V square wave. Collector current should be about 0 to 100mA square wave. (The 1.5V drive is to overcome 0.5V base emitter voltage.)

  • @2008007flavius
    @2008007flavius 6 ปีที่แล้ว +2

    Whats up my friends!!!!!

  • @apurvakalvade2301
    @apurvakalvade2301 5 ปีที่แล้ว

    From which instrument did u get that ferrite Core?

    • @MunnaKumar-sc7qo
      @MunnaKumar-sc7qo 5 ปีที่แล้ว

      desktop power supply or ATX supply

    • @apurvakalvade2301
      @apurvakalvade2301 5 ปีที่แล้ว

      @@MunnaKumar-sc7qo and in case if we don't want to use BNC connector and want the reading on the LCD _ then if we directly connect the output of the OPAMP to the LCD, will we able to get the display of current ratings on LCD?

    • @MunnaKumar-sc7qo
      @MunnaKumar-sc7qo 5 ปีที่แล้ว

      @@apurvakalvade2301 yes, but you must change the gain of op-amp as per you lcd working. If you control by any microcontroller then you must use ADC value range.

  • @eb2615
    @eb2615 4 ปีที่แล้ว

    Be very careful when using current transformers if you leave the secondary open circuit you can generate very high voltages when there is a current pulse or surge always terminate the secondary with a load resistor or are use back to back senders ect

  • @sonyobright2106
    @sonyobright2106 5 ปีที่แล้ว

    the 49e hall sensor has a bias voltage of half the power vcc ... means that the hall sensor would output a 2.5 v for a vcc= 5v with NO magnetic field sensed by the sensor ... the potentiometre help to offset that bias voltage ...the inverted configuration help for the gain. in this case 100. witch is too big in my opinion .. a gain of 10 will be more than enough.. another strange thing is the 9v battery that is too big for the sensor. in the end the filter is wrong and not suitable for this ...good work

  • @fatiherdan9510
    @fatiherdan9510 6 ปีที่แล้ว

    👍👏👏👏

  • @Frankhe78
    @Frankhe78 5 ปีที่แล้ว

    Ai lurt somtin new, click de lie butto an also sha de veedu. Leaf a common here.

  • @EASYELECTRICALENGINEERING
    @EASYELECTRICALENGINEERING 9 หลายเดือนก่อน

    What is Kurant

  • @francoisBonin-phils
    @francoisBonin-phils 3 ปีที่แล้ว

    if it was really ferrite , you could not cut it with a hacksaw , anyway , your video is great...

  • @sammin5764
    @sammin5764 2 ปีที่แล้ว

    🌟🌟🌟🌟🌟