Thank you for being my physics teacher, Mr. Chan. May you Rest In Peace. ❤️

@marianellaramirez3786

3 жыл бұрын

@Van Wang Appreciate Video clip! Sorry for butting in, I would love your initial thoughts. Have you tried - Franaar Shining Shape Formula (just google it)? It is a great one of a kind guide for revealing the secret to repair your electronic devices minus the headache. Ive heard some amazing things about it and my m8 finally got amazing success with it.

@RussellTeapot

3 жыл бұрын

@@marianellaramirez3786 @Avery Callan you dudes are massive jerks.

@labscience8271

2 жыл бұрын

@Adrian HD He passed away in the M/V Conception dive boat accident on September 2, 2019. Read his channel's description. Rest in peace :(

Thank you for posting. This is the best and simplest explanation I've ever seen. If you ever expand it, please add the same test for the amperage output of a solar panel.

How much fire is acceptable when performing this procedure?

Hey this is the best explanation ever on ampere measuring! Slow accurate and really newbie proof!

Doesn't say why there is a resistor, or what size resistor, or what happens if there is no resistor. If I don't have a resistor and bulb, can I use a PC fan instead?

Thanks for the lesson Mr Chan. I wish there were more but know there won't be. You sound like an wonderful teacher

You explained it to me in five minutes better than my professors did. Great video.

@technicalsohil4063

Жыл бұрын

true

@glenniie.forbes7527

Жыл бұрын

Lucky you, my professor didn't even explained it properly.

Thanks for sharing this video and information. It’s a great review as I initially studied Electronics in Lane Tech High School Chicago 1964. I am preparing to build a model train layout. I’m retired 74 years old. Appreciate your help though your videos!

Excellent , well done the best I have seen on KZread ! Thank you for posting. :-)

Love your vids and the quizzes . That is a really awesome thing so a person can actually obtain the information your supplying. 👍👍 ⭐️⭐️⭐️⭐️⭐️

Very Clear and useful, Thank you.

Thanks very much for this. Outstanding demonstration. Makes sense. You have to break the circuit to see the flow of current. I was very lucky I didn't break the meter before I saw this. Thanks very much.

Thank you so much :) I never thought it should be connected in series to the circuit.

Glad I watch your video first. Thanks for the info.

FINALLY.....a Clear explanation for measuring Current/Amps ........Kudos!.............Z

Thank you very much. I've been looking for this video for a while

Thanks Bro! Your video tutorial is well explained and I just learned something new.

What is the resistor for? And what will happen to the multimeter if you don't connect a resistor in your example?

@Hasan...

2 жыл бұрын

If he had done without the resistor, more current would then flow (higher reading would be measured on the multimeter). But he used the resistor to protect the bulb, so it's likely that without the resistor, the high current and full voltage across the bulb would have blown the bulb.

very concise and to the point, thank you

Now I get it....thanks for making it easy to understand 👍

You've just answered my question :) I probably blown my fuse by now ^^ Thanks.

Hi, i have a power supply 12v 20A connected to a step down convertor, i want to get a current of 5A using the convertor, like in your video where you used a lamp and resistor, what should i use so i can adjust the current from 20A to 5A? Thanks

Very very good tutorial. Thumbs up!

Thanks for making this video!

Great Tips Good Stuff Very Clear Understanding 👍 Thanks!

Thank You... Just the instruction I needed.

Thanks for a great demo.

Great tutorial. Thanks!

I have a cheap multimeter with 20A fuse that can do 15 sec. max C test. A couple of times i have tested batteries under 20A (without a circuit) and the cable got hot, so i always do 4 sec test. My meter is still okay, your advice is also good

hi Alls, may I know what value voltage and watt of the lamp that used in this video? I already tried and follow the step in this video with 24VDC 70W lamp and should be 2.9A by calculation right. but I only get 0.25mA. any idea?

Thanks you dumbed it down perfectly for me ....thanks big

Great info, thanks.So when measuring automotive devices I should know roughly how many amps the part puts out first?

@MrChanPhysics

7 жыл бұрын

Each circuit on a car is protected by a fuse. Each fuse is labeled with its maximum amperage. Almost every fuse in a car is at least 10 Amps, but the circuits generally draw much less current. The best use for the ammeter in a car is to find small "leaky" or "vampire" currents, meaning devices which are drawing current when you expect them to be off. A lot of electronics in modern cars (stereo, alarm systems, door locks) stay alive all the time and draw a small amount of current (10s of milliamps). So it can be useful to use the ammeter to find vampires if your battery is dying rapidly. For example, I had a car which drained the battery in a few days. It turned out that there was a small current drain in the power seat memory. One of the buttons was stuck "on" so it continued to draw current and kill the battery. Using the ammeter on a powered-on device like headlamps or stereo is very risky since they will likely draw more than 10 Amps and blow the multimeter's fuse. It is less risky to use a voltmeter at the device to see if it is receiving power. See my video "Measuring Voltage with a Digital Multimeter".

Wish I would have watched this before I fried my meter.DOOOOH!

@AdamTheAd-vanc3d

5 жыл бұрын

You and me both i killed some very hard to replace fuses.

@alberoDiSpazio

4 жыл бұрын

I have the same brand, strangly the fuse was intact. Upon closer look of the circuit I fried a tiny resistor (I could have re soldered).

@furkan10ky

4 жыл бұрын

Yeah guys I also have this problem. My multimeter just wanted to blow his fuse.

@BocaRetroGames

4 жыл бұрын

Same here hehhe

@equallywrong

3 жыл бұрын

lol. me too. my red wire got hot and the insulation melted. i caught it just before the meter fried.

hello sir, if i connect the multimeter after the led will the reading be different?

I am glad I found this video. I may or may not have blown a fuse because of my ignorance.

Silly newbie question, what if i want to work out the amps of the battery (not knowing what it is) so i can use this reading to work out my required resistor in the circuit?

Does it matter if you connect it before our after whatever is drawing power??

I understood before I finished watching..thx man

Excellent video..👌👌

very helpful video thanks !

I have a rechargeable shaver that has a power transformer that puts out 3VDC 120 mA. I want to see if the charging circuit is putting out the proper current. the battery is failing. (2/3 AA size - 2.4VDC 500 ma (two 1.2V cells in series. ) The shaver will not run if the battery is removed even when plugged in. So with battery removed and the circuit plugged in I measure on the + and minus pads where the battery was connect a voltage of 2.77 VDC. Can I test the current by putting the leads on the +/- pads on the board. (battery is removed) Would that be putting the leads in series?

@MrChanPhysics

7 жыл бұрын

No, that would create a short circuit and undesirable heat and/or smoke. To see if current is flowing, the ammeter must be in series between the battery and charger. Use an alligator clip lead to connect the neg. side of battery to neg. charger pad. Then connect red probe to the pos. charger pad, and the black probe to the pos. battery connection. Now the meter is in series. More than likely, however, is you have a dead battery.

Hi. Question: when the multimeter says 10 Amp DC, is that the maximum load it can test against? I have some welding transformers that I'd wish to know how much exact current they give... could I still use the same method owing to the fact they are somewhere in the 100 Amp range?

@techster8650

Жыл бұрын

Yes

If thats the case how can i measure my battary amp since its lebal is peeled off and missing?!

Can you check the amps of a circuit when it's not under load? I have a 12v power distribution module for which each circuit can have the amperage set by a computer program. I lost the programming cable, so now I want to check how many amps each circuit is set to so I can be sure I wire a new accessory to a circuit with the appropriate amps set. Or does the circuit need to be under load, and would I need to increase the load until the breaker tripped?

@MrChanPhysics

7 жыл бұрын

Current must be measured on a live, loaded circuit (unlike voltage , which can be measured on a live but unloaded circuit). Electric current is just like water flowing in a pipe; only when it runs is there anything to measure. If you do test the breakers for maximum load, please make sure that you don't burn down your shop.

How would u check currents (amperage) of a used Harbor Freight 25 watt Solar Panel with the same type of Ammeter .. is there a way to test the panel alone with no battery or load?

What if it’s a 12 volt battery do you move the settings to 20m and where do the leads go

Hi , I'm trying to do an amperage test on my stanley Jumpit jumper starter pack . Jumpit Jump pack rated at 1000 peak battery amps and 500 instant starting power . ..... On my jump lead of my pack red & black clamp ....... would you walk me through the setting on my multimeter to read amperage out from my pack lead ? Greatly appreciated .... thanks

best explanation, thanks you!

Thank you! I watched that video after I connected meter dirrectly to the source👌

This really helped me.. thank u very much

Hi sir.....what is the Value of your Resistor use?

thanks I was closing to damage my multi-meter through attach the terminals to the power source (laptop charger)

I did exactly what you said not to do. I just charged my 18650 battery and wanted to get a current capacity reading and I blew the fuses on both my digital multimeters and I just now purchased new ones from Amazon, I spent like $40 to get 4 fuses for both meters. Hence, why I am here.

Nice video, new friend here! Then how to measure the battery capacity? Let's say on battery cover mentioned 3500mah, how to know if it is really 3500mah or not, using the multimeter.

How do we measure peak amps? How do we determine how much of a load the battery can handle? Larger watt bulbs?

What would happen if you connect the negative lead(-) coming from the the amp meter/multimeter to the negative terminal(-) of the light bulb instead of the resistor(+) connected that's connected to the positive(+) terminal of the bulb? Would the amp meter/ multimeter still measure amperage drawn?

@levithatcher142

2 жыл бұрын

Just measures as negative if you reverse the leads.

Great vid - thanks - looks like I have to replace my fuse now, lol. I usually only deal with voltage/resistance for diagnosing car electronics, but I inherited a battery charger and wanted to test if it worked. Multimeter only supports 10A current, battery charger had a 2A (12v DC) option I wanted to test. I hooked it up in parallel to the battery on the loaded circuit, it sparked (the probes arched) a little when I connected the probes, no good reading, then unloaded, tried again, same results, now no sparks, lmao. Hopefully can replace that fuse. Should have watched this video first!!! I'll replace the fuse and try it in series this time... For the 20A and 60A settings, I have to buy a new multimeter I guess. Any easier way to validate these? Seems most multimeters I find only go up to 10A on the current.. EDIT: As a side note, if I test the voltage on the loaded circuit it's ~12.85 (typical charging output on a 12v auto DC circuit), but if I don't load it (if I test both alligator clamps that you'd connect to the battery) I only get ~9v. Is this normal? I would have expected to see 12.85 with or without a load. Thoughts?

@MrChanPhysics

7 жыл бұрын

To measure currents greater than 10 Amps, you will probably need an inductive-clamp type meter. It has a sensor that clamps around one wire and uses magnetic field to measure current. The clamp units do not require you to break the circuit, but the clamp can be clumsy to use in tight spaces. Make sure the one you use has capability of measuring both DC as AC (some only measure AC).

Urgent question for daughter's 3rd grade science project! We measure batteries in series and parallel connection. 2 AAA 1.5V batteries in Series go to 3V and supposedly the 1000 MAh stay the same, 2 AAA 1.5V in parallel stay at 1.5V but the Mah doubles to 2000, and 2 x 2 series connected in parallel go to 3V and doubles to 2000 MAh. I can measure the voltage increase or stay at same with the multimeter, plus I use a light bulb showing dimmer or brighter light, but how can I demonstrate the mAH increase for this purpose? I thought your video did that, but I get a reading of 0.12 and in parallel nothing changed. Using D or 9v I get the same readings when I though it would definitely be higher then the AAA battery. Do I need something else to show this or can this only be measure over time? Just a simple proof of hypothesis to double the mAh in parallel would be needed. Thanks.

@MrChanPhysics

6 жыл бұрын

The current (mA) will not change between 1 battery or 2 batteries in parallel (as long as the batteries are fresh and the bulb is a low-power flashlight type). The bulb is a type of resistor (R). The "formula" for current (I) is I=V/R. This is known as Ohm's Law. Since AAA, AA, C, D batteries all have the same voltage Vbatt, they will all supply the same amount of current I through a resistor or bulb R. If you put two batteries in series, then you have doubled the voltage Vbatt and according to Ohm's Law, you will see a doubling of the current I, and the bulb will glow much brighter. I=2Vbatt/R This also assumes that the bulb's resistance (R) stays constant. However, the resistance in real light bulbs increases as they get hotter, so you will probably see a little less than 2x the current I when you double the voltage. Putting 2 batteries in parallel will not double the current I. The way to show that is with 1 battery driving 2 bulbs in parallel. Each of the bulbs will use an amount of current I=Vbatt/R, so the battery must double its current output. Good luck with the science project!

Love your vids

Nice Tutorial.

thanks saved me some time!

Thanks. Just look this up. Very helpful video. 👍👍

how about testing current on circuit board like on laptop motherboard?

Can I touch the meter the the battery if the battery is a 9V battery?

Will the battery be damaged if u connect direct to battery from leads?

will it work the same if you disconnect the black lead and measure on that end?

@MrChanPhysics

7 жыл бұрын

Good question. Yes, it will measure the same because the current flows through all wires before returning to the battery in this simple circuit.

@oliverpalma4701

6 жыл бұрын

in that case, the negative terminal of the battery connects to the negative of ammeter and the positive of ammeter is connected to the negative terminal of bulb... am i right?

Hi MrChanPhysics. I have a stun gun that produces about 14,000 volt and I want to measure current on that gun. 1) Can I measure the current even though the multimeter can only handle 600 Volt ? Understand that I am measuring the current not the voltage because if I measure voltage it would burn out my fuse. 2) If it can be done then how would I measure the current in such a device ?

Is it possible to measure Ampere between the negative side of the load and the negative terminal?

@MrChanPhysics

7 жыл бұрын

Yes. Connect the positive probe to the more positive part of the circuit, and the negative probe to the negative battery terminal

Hi MrChanPhysics. I just watched your video. it looks great for me without any electricity or electronics background. I followed your tutorial piece by piece, setting exactly as you did BUT my multimeter read (1.) I am using 3AA batteries to operated a 3-led diodes of a PIR sensor light and I need to know the current so that I replace the batteries with a mobile telephone charger using the USB. Am I doing something wrong pls?

@MrChanPhysics

5 жыл бұрын

If the meter reads "1. " it probably means it is set to a scale too low to display the current. Try starting with the 10 Amp setting.. This may require you to move the red test lead to a different socket as I have shown in the video.

very nice tutorial.

hi is there a way to measure dc carbon brushes to say if they are ok for 12v or the difference if they are for 24v or 36v

@MrChanPhysics

7 жыл бұрын

I don't think the digital multimeter will tell the difference. A motor brush should be very low resistance for any application.

Okay, so you are using a "conventional view" of current flow. Actually in d-c circuits does not the flow come from the negative side of the battery? Should the set up and schematic show this?

Hi wat if I don't use a Resistor with the light ,, will that still work if I want to find the mAh of my 18650 lithium ion battery

Strait!!! I subscribe!!! I like how this video is ran.

Won't the current drop because of the load or Will it show the correct amps of the battery with load connected..?

does this multi meter need a battery? I do not get a display when its turned on

Good job! But what I don't know now, is how to do this (measuring current) off of a solar panel. Could you tell me pls? I have searched and couldn't see your video on this. Thank you in advance.

@MrChanPhysics

5 жыл бұрын

First, a warning. Do not attempt this with a large solar array. Some of them put out many amps at several hundred volts. This type of system is extremely hazardous and not for amateurs. I will assume you are trying to measure a small panel, up to 12 V and a few amps. To do it with this type of meter you will have to disconnect the positive output wire that goes from the panel to the load. Configure the meter for the 10 A setting (assuming your panel puts out less than 10A), then connect the red (+) probe to the panel output, and the black (-) probe to the load wire you disconnected from the panel. The load must be connected to get a useful current reading. Be careful with this much current. A better type of meter for measuring high power circuits is a clamp-on meter, which clamps around a single wire and does not require breaking the circuit or touching any live wires. Make sure you get one that measure DC current if you want to work with solar panels.

Thanks I have the same metter this is so helpful thanks alot

I am installing a video doorbell. It says my transformer has to be min of 16 vAC 10 VA, but how do I measure that? The meter only seems to measure DC amps. Why is that? Thanks.

Can I do for ac supply?

Can I measure Ac ampere for this multimeter

Does this work with 1.5V batteries?

If you're doing a AAA battery or even a D battery can you put the probes directly onto the battery tips or do you still need a circuit

@MrChanPhysics

6 жыл бұрын

yes but you won't really learn anything. You'll just drain the battery. The maximum current of a AAA is well under 10 amps but the voltage will drop when you short it out.

@shannonjoker8527

6 жыл бұрын

MrChanPhysics thank you

This test shows the positive line used. Can the negative line be used?

I've done this but it doesn't make a circuit and reads 0.00. Has the fuse blown previously with something I did long ago? I would have thought the mulitmeter just wouldn't work if that was the case By the way got the test correct at the end. EDIT: It is showing low battery on the multimeter... maybe that's why?

Boss, there is a way to measure AC current? I want to measure the output current of an audio amplifier to get the wattage..

@Twiggs8121

4 жыл бұрын

BisDak Philippines use the equation i^2 * R = W. So current squared times resistance equals wattage. Plug in your knowns and solve for i. For example, if your speaker is 50 watts RMS, at a 4 ohm load, take 50/4, then take the square root of that. That’s your current draw at maximum power.

Excellent presentation and demonstration! By the way, is a Bulb necessary to be linked?

@sraros

Жыл бұрын

Too late I guess, but anyway… Anything to draw current will do like a watt resistor, bulb or the actual circuit you want to test

Can we measure ac current on 220v ac supply

Thanks Great work

Nice informative video thanks.

Hi what can be if multimiter not reads the amps (only -1 appears and not create a circuit) but it reads voltage?

@MrChanPhysics

7 жыл бұрын

it probably means the current is greater than the meter can read or display. For example, if it set to a 2 Amp scale, and the actual current is 3 Amps, which exceeds the limit, it may display the -1. It may not be enough to blow the fuse.

@m.m1048

7 жыл бұрын

MrChanPhysics It should read 10A but the current that i want to read is less than 3A. The fuse was blowned in multimeter I replaced with a good one but doesnt help

When I first got a multimeter, I measured the amps of a common 1.5v AA battery by connecting the terminals directly to it. I don't remember exactly but it showed about a couple amps and rapidly declined. When I checked the unloaded voltage after that it had dramatically declined ie a good amount of energy stored in the battery got discharged within a couple of seconds. But the meter or battery didn't get damaged even though I tried to check it on the 2000micro A, 20 mA and 200 mA before moving onto the 10 A setting and it didn't even have a fuse. And it's a cheap Haoyue DT830D dmm. Btw how is the maximum amps from a battery checked safely?

@MrChanPhysics

6 жыл бұрын

Batteries have internal resistance which limits the amount of current they can supply. The maximum power delivered is when the load resistance equals the battery's internal resistance. Unfortunately, the internal resistance increases as the battery is depleted. I don't know an easy way to test for max amps from a battery with a single DMM. You could hook the battery to a variable load resistor (high power, low resistance), and measure both the current and voltage. Adjust the variable resistor lower until the voltage across the battery drops below its specified voltage, and measure the current. You could get more current by lowering the load resistance, but that would drop the voltage even lower, so it would be less power (voltage times current).

@pareshmhatre4019

6 жыл бұрын

I did the same

@michaelserrano7097

5 жыл бұрын

@Kamper Ken Happens to me. The fuse was intact, the multimeter was ok, but the wire came out like a spaghetti.

So that's DC power, but for measure AC current in 110v or 220v house electricity, most have something connected on outlet running on, that's right ? eg: transformer, coffee maker or something like that, drawing power.

Would 0.17 showing on a meter be a reading of 17 mili amps or 170 mili amps ? I'm doin a parasitic draw test on my car and this is the reading

@MrChanPhysics

7 жыл бұрын

If your meter setting is in Amps then it is 170 milliAmps. milliAmp = 0.001 Amp

@phillwilliams3399

7 жыл бұрын

Got u👌 my car should have no more than 50 mili amps so there is a draw there somewhere. Thank you very much

What if I used connection b?

You the man !

Thank you!

Where do the leads coming off the multi meter go, as they are not within the videos range? A picture is worth a thousand words, but only if the complete picture is shown. Thanks for the video.

nice video understood the consept

Great question. In the circuit I have shown, the current is the same through all parts. There are no parallel branches. So your meter will read the same current after the light bulb or before the light bulb.