Don't use a multimeter like this
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- Опубліковано 21 лип 2024
- I'm not saying these are great multimeter tips, I'm just saying they work.
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00:00 A bad digital multimeter idea
00:20 A digital multimeter (DMM) as a current source
1:21 A digital multimeter as a fused jumper
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#MultimeterTips #DigitalMultimeter #ResistanceMeasurement #DMMCurrentSource #DMM #Multimeter #Ohmmeter #MeasureResistance #UseaDMM #KeysightDMM #SmartbenchEssentials #keysight #electronics #electricalengineering - Наука та технологія
We were so preoccupied with whether or not we could, we didn't stop to think if we should.
No, you patented it, you packaged it, you slapped it in a plastic lunch box and you sell it! You sell it!
*music noises*
Keysight, Agilent o HP whatever you want to call it make low quality products.
I bought ond Agilent oscilloscope paying Us$1800 dollars, I bought one Us$200 dollars cheap scope and works much better in every posible way.
Years ago I was working in a company with Us$100k dollars Agilent scopes, all fail every 15 days, totally garbage.
Hand multimeters are the same, Fluke is much better.
Sorry.
What is this Mul-Tie-Meter you speak of?
One of my favorites: Your U1240B has 10MOhm input impedance in normal DCV mode. You can extend the 1kV input voltage range by measuring voltages with a resistor in series with the DMM. i.e. +10kV --- 90MOhm --- 10MOhm DMM --- 0V this could read up to 10kV, but other values and higher voltages are possible. Better than tongue test, that's for sure.
If we are abusing DMMs today, lets replace that 90MOhm resistor with 9 other DMMs in series...
use the voltage input impedance to measure really small currents
If only the case and pcb were rated for such high voltage;)
@@LordPrecision , You took the dopey words right out of my mouth... LOL DAMN, is that a really dumb thing to do! BUT IT'S SO SIMPLE! de KQ2E
@@fredflickinger643 , That is what MR/TROLL said in that first comment.
Hold Y to dual-wield got me right in the giggles!
One of my 'top shelf' ideas: you can use the internal high value resistor in the DMM, as a, you guessed it, high value resistor.
These ideas are SO BAD, that I'd only try them if I Won a FREE Keysight Multimeter.
This was the best video of this year's KU Live so far :-D Well done.
Thanks!
Definitely!
I have used my DMM as a fuse for many projects where I didn't have a fuse or fuse holder handy. Better than setting things on fire and tripping the breaker!
I just use DMM to make LEDs glow. My way of testing LEDs
I'm in need of a new set of jumper wires, now I need to buy a bag of DMMs.
You can use the different bias currents to use a DMM as a crude low current SMU.
The compliance voltage will also be quite low.
Another "bad" idea: to test a battery for its health in "current measurement" mode - technically short the battery through a DMM. If the measured current is large enough (for this particular kind of battery) - it is good.
These videos are great. I was listening to some boring recorded lesson - saw this bad boy come up. Had to click it. Thanks for making my studies more fun.
yep, definitely have used a cheap DMM as a fuse box before lol
Excellent tips 😃, I think most of us short things together in the 10A mode, it's the most used terrible idea.
Who else has tried to measure mains voltage with your probe in the 10A socket?
@@abraarsameer9521 That usually means goodbye voltmeter.
Sometimes i do it because the probes are really good for... You know... Probing
@@zyeborm Good point, I think everyone does this 😅
@@abraarsameer9521 oh god. I did that 2 weeks ago. I didn't intend to do it. I just forgot the probe was at the 10A socket.
The moment i put it in i hear a big spark and light comes from the plug extension (did it in my house) and i also hear the safe of the house turn off. I was sure i completely bricked my multimeter (a cheap a$$ 20 euro one). I was shaking from excitement and fear since it was my first time happening to me (I'm a beginner). I quickly open the back panel of my multimeter expecting a mess inside but... it was fine? I check the shunt resistor and the 10A fuse but it hadn't been burned. That puzzled me. I try to measure voltage, current and use the other functionalities of it but they worked fine. The tip of one of my probes was melted tho and the metal part of the socket was too. The most logical reason for this is because the breaker kicked in fast enough for there to be no damage but it still feels strange.
You never cease to amuse me Daniel! You're like the Electroboom but for Keysight! Next video, I'd like you to measure 100 amps with your N9042B. It doesn't make sense to measure current with a 50Hz to 50GHz bandwidth spectrum analyzer. But you can do it because you can. That's OK if something happens to it; you work there and they'll give you another one lol
A handheld DMM is great for rough performance verification of used test gear (e.g., at auction previews). It's a voltage reference, current reference, resistance reference and, with the U1252 and U1282, signal source. It's not a substitute for the home lab, but packs a lot in a portable package.
I use the current shunt short a LOT , it is very convenient when the wires are far away and you feel lazy.
I often use an analog multimeter in resistance mode to test LEDs, it can deliver a snall amount of current (like 20-30mA) and depending on the scale you use the LED will burn lol
Used my DMM as a wire more often than I'd like to admit. Pro tip: short your fuse with a thick piece of copper for extra current throughput
Uhhhh
@@KeysightLabs Next video: how to use multimeter to discharge capacitors
Love it!!! I work in Logistics! So cool to see the machines and people at work!
A dmm as a low value CC source can be handy when testing analogue panel meters although a better way is to use diode mode and a series pot.
Yes, these tips are god to go!
You'll eventually need to check your meter performance using a good known multimeter
My career started out with a Simpson 260 multimeter. You learn to be extra careful with probes and settings. I use a Fluke most of the time but I still have a Simpson 260. no battery needed and its a great way to get a reality check on the DMM.
Yeah, I've used the current setting to bypass a bad starter motor relay.
Got me going to the parts shop :)
Hello. What are you think about Hantek hdm3065 multimeter?
Thank you for teaching us :-D The Jumper Wire Feature is great, also already used it ;)
Excelente equipo
I'v use the dmm in current mode as jumper wires to test some 12v relay in a terminal block...
I've totally used diode mode as a current-limited, isolated voltage source (in this case, testing a newly-refurbished amplidyne!).
What, no nano amp range using the 10 meg input resistance in voltage mode?
Also DMM FUSE 10A or 20A... Test leads with crocodile... Not 10A rated continous ... I know ;)
Would be fun to see what are the CAT III IV 1000V 600V rating and what happens when you ignore these suggested limits. Probe gauge ratings etc etc...
Man,.... head hertz,... a venn diagram of can/can't and should/shouldn't. I love it and that's why it hertz.
Is current always constant or only "known" by the device?! I mean, it might vary a bit as long as its value is known at each time when sampling..
I'm use the diode test as a source of voltage when I have the need to simulate a input voltage to a sensor circut of a car as it can be verified on a scanner and the dmm and no magic smoke if you get the wrong pin.
Thanks for your awesome tips sir.😂
So I tried this out and a question arose from the results . How do you remove multimeter smoke from the kitchen before my wife gets back ?
I use function very offen when I need to reset uC or a module or whatever
I use the DMM as jumper much more often than as ammeter. I use the resistance measurement function as voltage source. Now I learned something. I can changed the voltage output via the range
I have done both of those things. Very old DMMs work better as a precision current source because they typically have am much higher compliance voltage.
My tip would be that you can use the voltage measurement mode to measure very low values of current with an effective internal shunt resistance of 10 megohms. So for instance one of my meters has a 200 microamp range with a resolution of 100 nanoamps. But in the 200 millivolt range with a resolution of 100 microvolts, it has a range of 20 nanoamps with a resolution of 10 picoamps when measuring current.
I will never forget this and you're just going to have to live with that.
You could put thermocouples in the motor and battery of your e-bike and use a DMM as dash board gauge while you tune.
Guilty of using the DMM's A range as a jumper... But at least it was low current: basically ground a Chip Select of a PC motherboard and enable its ShadowBIOS to bootstrap it. :P
One question, though: I noticed your U1282A is not beeping like a madman when switching to any of the current ranges. Mine runs the beep alert at least five times, regardless if the probes are in the correct A/mA/uA jacks. Is there an option on the setup menu?
(BTW, meter has latest FW and was never opened nor "submerged" in water/oil/mist/etc)
Sorry for asking this here, but that is one of my major beefs with my 1282A - otherwise, it is one of my go-to meters!
I use DMM in ammeter mode as a jumper quite often :D
I often short switches with the DMM, this way I can measure how many mAmps a function draws. Last time it was a reset switch (6.2 mA so the fuse was safe^^)
Can keysight make 5 digit clamp meter with high end componets
I used 10A current mode for testing PLC inputs, relays or contactor using it as a jumper from 24VDC or 120VAC to PLC input or relay/contactor coil or even test a pilot lamp in a control panel. I think the key there is to make sure the current that will be drawn will not exceed the 10A fuse. For PLC inputs, any digital inputs or even relays and contactor coil, it will never exceed 10A. Typically less than 2A.
What about DMM's voltmeter as na nano amp meter for mesuring reverse current of rectifying diodes?
Just put it in series with a diode.
Several mV / 1Mohm = several nA of current...
and several mV stands for next to nothing comparing to even single volts of reverse polarity....
I know all these, but I don't know what are you trying to show. thanks for other good videos.
Some uber cheap DT830 dmm has 1 megaOhm input impedance, works almost like a low-Z (low input impedance) dmm.
Many time I got errors on measurements because their loading effects on circuit under testing is 10x more than common 10megaOhm impedance dmm.
Have used my DMM as a jumper, did blow the fuse, would do it again.
That is, once I replace the fuse.
Those stinking 11 amp Bussman DMM high rupture fuses are like $11 apiece, and we never have them in stock! (I wonder why?)
yup, been there, done that and fried a few fuses in the process...
or measuring charger performance on a 12V 18Ah battery: first measuring charge current, then don't replug the wires, only set the DMM on voltage and try to measure voltage across the battery :)
if you think line voltage is dangerous? go mess up some batteries!
I like the ideas in this video
Get a high-enough voltage DC source, e.g. 100V
Connect DMM to it. Null the reading. (click REL)
Connect a zener or TVS in series to check the zener voltage.
It will show lower because 10uA, but you know what to expect, enough to sort/check :D
Thanx I was doubtful like wait it’s just a multimeter
Nice dual wielding there!
The DMM as a current source is a very good idea, usable during a quick and dirty JFET common source characterization? Or maybe not, don't do it :D
(I have to try this ASAP)
Impressive dual-wield. But srsly, what the hell was this xD
Love you guys for having humor! Wish I could affort one of your Scopes to support you :D
Geeze, it's still valuable info!
I try :)
I mean, I used my DMM to measure the frequency of a tesla coil and end up destroying the current measurement circuitry...( it was actually the DMM measurement IC, but somehow it only killed the 10A current measurement)
I have a question for you.... please answer me.....
If I have lower frequency current around 20cycle per minute does capacitor improve frequency
Capacitance does have an effect on resonant frequency
If you put two identical DMMs in series across a 100v DC source what would they read ?
Each would read 50 volts.
Shorting stuff using the DMM? Been there, done that. Especially when you need to temporarily short something on a PCB and have a nice set of sharp DMM test leads (like the 34138A). Yeah... I guess I could get myself one of those female to female banana jack adapters.
A spiky current waveform? DMM shunt resistor and oscilloscope (just fix the DMM current range)
Perhaps you can try using a Wheatstone bridge to measure the impedance of the powergrid😱
none of them is actually outworldishly unfeasable
in case you know what your doing and that it will not kill your equipment
I always use my hand held DMM as jumper wire 😁
not recommended
Now I can't un-see this. 🥵 I'm still shaking from the thought of you almost putting DC voltage straight into the VNA! 😅
😅
I’ve blown up other equipment by unintentionally using a dmm as a short when intending to measure a voltage... Doh! DMM was fine.
can i have one of those scopes
good finds.
i use most of these as hacks in one form or another daily just for lack of equipment/supplies lol! there's also the horrrrrible idea of harvesting less essential parts that can be useful for fixes, while still maintaining functionality. eg: the 9v battery socket from the multimeter to whip up a makeshift soldering iron and just solder the battery to the board with the remaining wires and said soldering iron...i could go on..
Wish I had a physics teacher like you, when I was young...
Wow name/model number of the power supply please
Name/model number of the oscilloscope
Sure thing!
Supply is an E36313A:
www.keysight.com/us/en/products/dc-power-supplies/bench-power-supplies/e36300-series-triple-output-power-supply-80-160w.html
and the scope is DSOX1204G:
www.keysight.com/us/en/support/DSOX1204G/oscilloscope-70-100-200-mhz-4-analog-channels-waveform-generator.html
When there's no room in the budget for proper tools, make your own.
I always use my multimeter in resistance/continuity mode to test LEDs because it doesn't have a diode check function
That's a clever workaround!
I see what this is about. You're trying to get people to ruin their test gear so they have to buy more. :)
Placeholder for when I use this efficient ideas.
damn, you actually guessed how I discharge in-circuit capacitors. :D
Using the "lo-z" mode on your DMM?
Keep in mind: The man making these suggestions sells replacement DMMs
So how many can I put you down for?
@@KeysightLabs Wait until I fry one using it as a jumper. You can ship overnight, right?
If your DMM has a 10M input resistance, you can set it to 200mV and bingo! you have a 20nA range.
Multiple DMMs do not have 10M input impedance at low voltages. Quite probably at 200mV range it has > 1G
@@ikocheratcr Yep. Hence I started my comment with "If". 10M across all voltage ranges isn't universal, but it is very common.
The KULive2 link doesn't work... but KULive1 still does! Is that a typo?
Ah... there are weird characters at the end when you click on it. Deleting those works!
Weird! Working on it
You can also "misuse" an oscilloscope as a fast, low voltage voltmeter.
My Keysight DSOX1202G has an actual digital voltmeter embedded and not just using the 8 bit ADC to sort of measure voltage. It's not super sophisticated but a lot more precise than the 256 count of the 8 bit ADC.
that is funnier than i expected it to be.
I use dmm for measuring very high resistant stuff, kinda of insulation tester.
You need a known stable voltage source, like 9V battery or simple 1kv dc voltage source; current requirement is very low.
Put it in series with dmm and things that you measure and mathematically calculate the high resistance measured based on your 10megaOhm impedance dmm voltage reading on basis of volatge divider resistor.
Similar to what nS (nanoSiemens) range did on dmm.
Other things I learn from MarcoReps is to read capacitor leakage current, similar to measurement as above but you calculate by I=V/R, where V ia your voltage reading & R is your dmm impedance.
Try to get dmm with stable (known of measured by othe dmm to make sure) 10 MegOhm impedance, some cheap chinese dmm will auto high impedance on low voltage range.
Other things, some cheap chinese dmm (4000 or 6000 counts) can do up to 3.999A or 5.999A dc current measurement before autoranging on 10milliOhm shunt, that means your dmm can measure voltage down to 10uVolt, which may or may not available to you on normal voltage measurement selection.
I'm thinking of removing those shunt and use those dmm for very low voltage measurement, surely at equivalent of 10Amps you'd only be able to measure 100mV (or 39.99mV or 59.99mv before autoranging).
Should you need to measure high current then use known proper external shunt.
Now I wonder if that's possible to measure AC signal in the order of 50-100uV (or even lower) as most DMM will struggle on mVAC range to measure that ?
Common wisdom is just to use proper AC millivolt meter with range capability of your needs (10uV resolution/sensitivity?).
Wow!
Thanks, I hate it.
I need a precise current source that can measure resistance 👍
Like that time I used a VNA as a RF signal generator.... I mean, its not a great idea, but if someone has stolen your RF signal generator, and you need to get the test done...
I discharge Supercaps using a multimeter. This video relates me
i used my multimeter as a power source
and the probes as jumper wire 😁
You'd think a bunch of engineers would have the knowledge and wisdom to restrain and advise others to do the same, but nope
I mean that's the best summary of this video I've seen yet
I always use my DMM as a jumper wire
Usually, I'm using multimeter in diode mode as power source to test unknown clear LED's color an verify, that this LED is working and polarity is correct.. Basically, same as testing other n-p/p-n device, that's mean's no harm to DMM..
Few times I used multimeter as fuse.. But in my case, I want, not only connect two terminals, but measure current too.. When cars fuel pump stops, I removed relay, and touched with DMM probes in current mode to the relay terminal.. In field this method work as a charm to understand what's going on! 😂
Basically, this needs to be done smart, otherwise, something can be shortened out through DMM.. 😂
I just wish i could afford this level of tool
Believe it or not, some of us noobs learnt something we didn't even think to ask.
I am curious as to why these are bad ideas. Often when I am connecting things together with a DMM, I am also curious as to the current in the line, so having that additional information is nice. Sometimes I insert the DMM to measure this current even if do not need to use it as a jumper. Provided you do not exceed the recommended current then you should not damage the DMM in this way.
I see this as potentially harmful to your DMM, only if not operated safely (the same for any test equipment setup), so perhaps that's why it's a "bad idea"
Now, I can see how using the ohms range as a current source may backfire and create problems. As I recall, this current source is very low power, and therefore cannot output much voltage (so it is not very useful except to measure resistance). I can see how connecting this to an improper load (high capacitance, very reactive etc.) may damage the current source, and if the load voltage is high enough, the front end of the DMM) But you are unlikely to damage it by connecting it to a resistor, and I imagine some active devices like diodes would be ok too. Having this current source available may be useful for very low power testing of semiconductor devices, as most labs do not have a uA or nA precision source.
I see this as "not particularly useful" even though it's not particularly dangerous, so perhaps that's why it's a "bad idea."
Still: Great video! It's always a good idea to understand how your test equipment works to ensure you are operating it safely and you can ensure your test setup is reasonable to obtain the results you need.
One vote for DC Sourcemeter video please!
One time I used DMM in current mode as jumper wire while testing high voltage LEDs. So I have one lead directly from mains and another from DMM in my hands (with 220V AC on it) and bunch of LEDs lied down on big heatsink. As a bonus I was have current measurements and fuse. Don't do this at home.
Yikes!