Power factor meters - how do they work, teardown, experiments

  Рет қаралды 31,242

DiodeGoneWild

DiodeGoneWild

2 жыл бұрын

Exploring the mysterious internals of analog power factor meters and explaining how do they work. They measure the power factor of linear loads (resistive, inductive or capacitive). The power factor is the cosine of the angle between the voltage and current. It's 1 when the angle is 0 degrees (the current is in phase with the voltage).
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Пікірлер: 133
@ForgottenLore
@ForgottenLore 2 жыл бұрын
Wow, things from this era are so nicely made. Even the needle has a cool design. :)
@attilarivera
@attilarivera 2 жыл бұрын
I agree.. It is hard to find these components now a days. ✌😊👍💚💛💙🇧🇷
@bluerizlagirl
@bluerizlagirl 2 жыл бұрын
They were only used on big industrial machinery and in electrical substations, so there would not have been many made. Scientific instruments used to be hand-made, and instrument makers wanted to produce items that were as beautiful as they were accurate. After all, people were paying a fortune for the equipment ..... Modern mass-produced equipment does not do an objectively worse job than artisanal instruments, but it's just nowhere near as nice.
@amydamon2323
@amydamon2323 2 жыл бұрын
You did an amazing job of explaining power factor and phase shifting by capacitive and inductive loads. I had a basic understanding of the subject from other KZfaqrs, but a power factor meter was still a "black box" to me. Your drawings and demonstrations have made it all clear. A bloody good job! Thank you.
@MissNorington
@MissNorington 2 жыл бұрын
First time ever seeing 3 phase stuff that isn't on animated paper (KZfaqrs sure know how things like electricity work, in theory only, you are the first one who actually connected them up for real!). Your capacitors are rated 400V and apparently your body as well
@antibrevity
@antibrevity 2 жыл бұрын
Very nice. You did a good job estimating what resistor box should be on the phases for the 2nd meter. I do suspect that more current was needed to make the needle move properly, but better safe than sorry with such wonderful devices that you don't want to break. Few of us are old enough to remember when things were built sufficiently well or sometimes even over-built instead of drastically under-built as they are today.
@tactileslut
@tactileslut 2 жыл бұрын
That little damping setup with the non-ferrous plate and magnet is brilliantly simple.
@airmann90
@airmann90 2 жыл бұрын
Excellent explanation. Beautiful old gear. Gotta get some old meters now haha
@BritishEngineer
@BritishEngineer 2 жыл бұрын
Great video diode! Edit: you are one of my favourite electronics KZfaqrs.
@frogz
@frogz 2 жыл бұрын
you're a damn good teacher, i've seen dave jones, bigclive, diodesgonewild and even linus tech tips explain ac current lag and you did the best job sofar!
@kyawzin3957
@kyawzin3957 2 жыл бұрын
This Zebra Cat knows what we want! It said, "Enough theory and show internal"! Love it.
@JohnOverstreet
@JohnOverstreet 2 жыл бұрын
Thank you for showing us how it works and how the meter internals are arranged.
@TheEmbeddedHobbyist
@TheEmbeddedHobbyist 2 жыл бұрын
Interesting that you have a 3 phase supply to your house, UK is single phase to each house with the phases balanced out in the houses in street. So next-door could be on our phase but across the road on a different one. They liked to keep 415V away from us. :-)
@ratbag359
@ratbag359 2 жыл бұрын
we used to get two if you were lucky one 24hr the other controlled but also depended on what phase the controlled was taken from.
@edgeeffect
@edgeeffect 2 жыл бұрын
I didn't realise we could get different phases from other houses.... this could lead to some SUPER DOGDY experiments with long extension leads up and down (and over) the street. ;)
@SeanBZA
@SeanBZA 2 жыл бұрын
You can get passive PFC to be closer to a sine wave using a capacitor across that series inductor, tuned so that it is resonant at around 3 times the line frequency. That way the current in the diode is both on for a longer time in conduction, reducing the loss in the diode, as lower peak current flows, plus the capacitor gets charged for a longer time, and you get a much more closer approximation to a resistive load presented to the supply. Of course will have extra loss due to loss in the winding and the inductor core, so they need to be thicker copper wire and finer sheets of laminate to reduce loss. The major advantage comes with very high power, where active systems still struggle with power density, and also they add to the filtering on the input side, so are common at high power with large DC motor loads and very high power inverters, as this is easier to implement over wide input current than active compensation. Of course with high power AC motors the easiest is a synchronous motor as part of the plant, delivering some always on large load, that is over excited so as to appear to be capacitive, allowing you to use the power factor meter to control motor excitation to make the overall power use of the plant resistive, as most big plants pay for reactive power at a very high rate, so power factor control is important for them.
@RODALCO2007
@RODALCO2007 11 ай бұрын
Excellent demonstration and explanation how these power factor meters work. Those older type PF meters are very well made. Pieces of superb electrical engineering.
@Pirelli.
@Pirelli. 2 жыл бұрын
8:12 😄 Thank you Dany for this great explanation!! Have a nice week and god bless you!!
@Geniusinventor
@Geniusinventor 2 жыл бұрын
Wow, I didn't know, that this kind of indicating Meter was made it's looks soo interesting. Thank you for your work on this video I appreciate it.
@kellymarieangeljohnson114
@kellymarieangeljohnson114 2 жыл бұрын
Thanks for a really good explanation was clear and easy to understand. I remember in a factory where I worked there were power factor meters on the mains intake panel we had a large metal box with capacitors in to keep it near 0.95 occasionally the capacitors would switch in or out they did it automatically
@beatrute2677
@beatrute2677 2 жыл бұрын
Great vid man. Learnt a lot here
@CanizaM
@CanizaM 2 жыл бұрын
The coils are not 90 degrees apart, because the reference phases are not 90 degrees apart either.
@peterbrown6224
@peterbrown6224 2 жыл бұрын
Your videos are always first-class. I'm just here for Cat.
@nobody-vw9ci
@nobody-vw9ci 2 жыл бұрын
I always feel like I have learnt something new whenever I watch your videos and I don't feel bored unlike in class.
@Edisson.
@Edisson. 2 жыл бұрын
Tak tohle bylo hodně zajímavý a dobře podaný 👍
@YouTubeviolatesmy1stamendment
@YouTubeviolatesmy1stamendment 2 жыл бұрын
Yeah I was going to say in vertical position it looks like the needle has to fight gravity which would push it more toward capacitance reading You could have checked the balance of it by shifting the two phases back and forth it should have read exactly the same reading and either capacitance or inductive if there were no other forces on the needle
@jp040759
@jp040759 2 жыл бұрын
Great topic. Always wondered how these meters worked. Thanx
@fabiomuzzi7047
@fabiomuzzi7047 2 жыл бұрын
Really nice. These old meters are really interesting.
@surinperera4041
@surinperera4041 2 жыл бұрын
I really like your explanation sir. Thanks
@RocRizzo
@RocRizzo 2 жыл бұрын
Thanks. Very informative
@shayhsopwagqehghggtfyggty2635
@shayhsopwagqehghggtfyggty2635 2 жыл бұрын
Nice video!
@tdtrecordsmusic
@tdtrecordsmusic 2 жыл бұрын
You did a great job explaining everything. I'm bookmarking this & studying in depth later. I wonder if i can make some meters from this vid. I'm honestly considering it...
@CoolDudeClem
@CoolDudeClem 2 жыл бұрын
I often wondered why flourescent lights (that use a magnetic ballast) often had a capacitor across the mains, now I know. If I remember, the light in my room has a 10uf cap across the mains.
@mjouwbuis
@mjouwbuis 2 жыл бұрын
There's a second reason. On dual tube lights, a capacitor is in series with one tube, both compensating for the inductive load and for doubling the flicker frequency of both tubes together through shifting the phase.
@ElectroRestore
@ElectroRestore 2 жыл бұрын
Awesome video! I would love to see you do a follow up with a scope on the phase shifted signal wire. :)
@cmuller1441
@cmuller1441 2 жыл бұрын
To find the best match for the fluorescent light you don't really need the power factor meter. Just the amp meter: just find the minimum current. Of course the pf meter helps by giving you the direction of the adjustment you have to do: more or less capacitance.
@bjornroesbeke
@bjornroesbeke 2 жыл бұрын
These analog meters have a charm, unlike digital meters these days.
@16BITMEME
@16BITMEME 2 жыл бұрын
Please make more videos on Geiger counter how to build
@MainkraftiwiczPL
@MainkraftiwiczPL 2 жыл бұрын
I love seeing your videos. I'd love to see video with synchroscope on your chnnel. Synchroscope is the meter to synchronize generators in power plants to te grid
@shivtherock5302
@shivtherock5302 Жыл бұрын
Nice bro....your style is awesome....love from india Upload calibration procedure also of that
@lukasb95
@lukasb95 2 жыл бұрын
Wow, so long videos! I wish you can make a videos about the Active PFC waveforms when the input power is not perfectly sinusoidal (like when using modified/approximate sinewave UPS) also, on the last UPS videos, the peak voltage can go over 400v. Does the input bulk capacitor gets that voltage & is it safe? Also will the Active PFC circuitry confused when its input power gets higher than the target output voltage
@38911bytefree
@38911bytefree 2 жыл бұрын
Nice exaplanation. How elegant were the old solutions ....
@jmr
@jmr 2 жыл бұрын
Now we just need to see how they measure frequency.
@petrcibulak5038
@petrcibulak5038 2 жыл бұрын
kzfaq.info/get/bejne/rrB3prmj2J-pnGw.html
@tactileslut
@tactileslut 2 жыл бұрын
Fran had one on the bench that looks like a row of music box tines. The idea was the one resonating would look different. I wish she'd driven it with a signal generator and power amp.
@haczyk84
@haczyk84 2 жыл бұрын
Great video with lot of knowledge. at @23:18 there are 100V at meter so I will try calculating resistors as voltage divider with coils resistance, so after powering it up there should be about 100V at coil. Maybe inductance make some differences but I fill it will be good enough method.
@ivanbratanov8699
@ivanbratanov8699 2 жыл бұрын
That is a very sweet english pronunciation! Great video!
@Mrdibzahab
@Mrdibzahab 2 жыл бұрын
Behind/ahead are somewhat confusing terms when looking at those repeating signals. Is the current behind the voltage cycle or ahead of the next cycle?
@Anvilshock
@Anvilshock 2 жыл бұрын
If you manage to make phase shift beyond 180° (or -180°), let me know.
@byronwatkins2565
@byronwatkins2565 2 жыл бұрын
For single phase systems, simply put the same reference phase into both reference terminals. When the meter face is vertical, you are lifting the weight of the needle and more current is required to approach 1.
@atmsc4nd4l
@atmsc4nd4l 2 жыл бұрын
wow. i am looking for this and you've just make one.
@loganmacgyver2625
@loganmacgyver2625 2 жыл бұрын
As a guy studying electronics in a vocational highschool CosФ anywhere gives me a panic attack (Don't take it seriously please)
@LMB222
@LMB222 2 жыл бұрын
I learned about cos(phi) in a vocational school… without using complex numbers. It was a nightmare.
@01Hudesohn
@01Hudesohn 2 жыл бұрын
I'm curious about the Tester. I have one myself and I've noticed that it has Problems correctly displaying what it is for certain parts. For example, a Transistor is shown as an N MOSFET. But that's the only thing wrong. Resistors and Capacitors as well as Coils are displayed correctly.
@KeritechElectronics
@KeritechElectronics 2 жыл бұрын
Lovely view of a device not really common nowadays :) BTW I've got the same (or at least very similar) component tester.
@mekonenhabtemariam1158
@mekonenhabtemariam1158 Ай бұрын
Very good explanation and please about synchronization say same thing
@esunayg
@esunayg 2 жыл бұрын
what about smps circuits? they are using the upper part of the voltage peak. is it capacitive or inductive?
@ratbag359
@ratbag359 2 жыл бұрын
none it is distorted looks resistive but only at the peak of the waveform.
@stevebollinger3463
@stevebollinger3463 2 жыл бұрын
A SMPS receives rectified and smoothed AC. It doesn’t run directly off AC. So it has the circuit shown at 36:26. Is is capacitive due to the input smoothing caps. But really it is more distorted than capacitive. There are power factor correction chips which adjust for this.
@esunayg
@esunayg 2 жыл бұрын
@@stevebollinger3463 I havent watched the end of the video the first time I watched it. But then completed it. Thanks.
@Bobit53
@Bobit53 Жыл бұрын
It turns out that the power factor will affect the heating of the wires and bigger power consummation? But does it affect electricity meters, like an kW counter?
@bluerizlagirl
@bluerizlagirl 2 жыл бұрын
I guess nowadays it would all be done using analogue-to-digital converters and measuring the time between zero crossings in each phase to get the frequency and the phase shift. I'm sure that is how the plug-in ones work. On the one I bought several years ago, it looks as though the same housing could easily have been fitted with different inserts to suit different countries. Still, it's impressive to see how it all used to be done using purely analogue devices! And these were built with care like old-school scientific instruments by craftspeople who took a pride in their work, not mass-produced down to a price point so some beancounter can get a new sports car .....
@5Dale65
@5Dale65 2 жыл бұрын
It definitely must be. Every household wattmeter you can buy for like 10 EUR has the power factor measurement implemented. And it's pretty accurate. It's some kind of electronic black magic.
@volleswerkfullorganpower249
@volleswerkfullorganpower249 2 жыл бұрын
My favorite subject
@bx4hy7kr7p
@bx4hy7kr7p 2 жыл бұрын
レトロなコレクション、いいね。
@lmwlmw4468
@lmwlmw4468 2 жыл бұрын
Nice.
@Skracken
@Skracken 2 ай бұрын
On the two older meters, I think what they need to work 100V for the first one and 380V for the second one, and up to 5A on the current input for both. Like it says on the front of them. :) But yeah, like you said, risky if you aren't sure. I have no personal experience with electromechanical pf meters, we use digital power analyzers in our panels
@jacksonv1ll836
@jacksonv1ll836 2 жыл бұрын
Can this PF meter be made using wall clock or pendulum clock 🙂
@andrezinatech
@andrezinatech 2 жыл бұрын
NIICEEEEEE!
@mernok2001
@mernok2001 Жыл бұрын
I got shocked first time when i was about 8 years old. Now because you handle mains voltage temporary setups like me i guess you also already got shocked at early age.
@movax20h
@movax20h 2 жыл бұрын
Great video. I am sure somebody will find original schematics / manual.
@EdgarsLS
@EdgarsLS 2 жыл бұрын
actually you dont need a common connection for 3 phase loads, because the sum of all the voltages at a given time will be 0V ideally, but imbalanced loads or varying voltages will make the common voltage look like it's not 0V, not a big problem for meters but for AC motors where the metal case is connected to the center of the Y connection, it's a good idea for safety to connect the common terminal to ground anyway.
@celsoneves2368
@celsoneves2368 2 жыл бұрын
Beauty!.
@piconano
@piconano 2 жыл бұрын
I love these old Soviet meters. They're built like a tank but still manage to do delicate work.
@5Dale65
@5Dale65 2 жыл бұрын
Although Czechoslovakia was not an (official) part of the Soviet Union. But still the equipment produced back then was really reliable and lasted for decades. Not like nowadays' plastic disposable shit
@LMB222
@LMB222 Жыл бұрын
It's not a Soviet product.
@JohnDuthie
@JohnDuthie 2 жыл бұрын
I'm so confused I wish someone did a comparison of inductance between different types of inductors. Iron core, Ferrite, and Open-Air would be interesting. I'm reading an article now but it's hard to grasp.
@haczyk84
@haczyk84 2 жыл бұрын
core matters :) are you searching for radio, power conversion or just like that?
@LMB222
@LMB222 Жыл бұрын
It's irrelevant for this video - here you have inductive or capacitive power factor.
@kokotajebka
@kokotajebka 2 жыл бұрын
18:52 you also can find the power factor 1 by finding the lowest current showed by your ampermeters
@DigitalBhangari
@DigitalBhangari 2 жыл бұрын
Diodegonewild is the closest reincarnation of Nikola Tesla.
@BritishEngineer
@BritishEngineer 2 жыл бұрын
Photonicinduction
@sirusgalt5931
@sirusgalt5931 2 жыл бұрын
I have very little electrical knowledge and have spent most of my life throwing things away when they stop working. Im intrigued by an idea that a alot of simple electronics can be made by hand and likely better than store bought. Is that the case or is everything so specialized now that aquiring the various components and the time it takes to make things, outweigh the benefit of making it yourself?
@LMB222
@LMB222 Жыл бұрын
Don't throw lut. 9 out of 10 times there's something banal, like a fuse inside, or a broken plug. You need a knife, a screwdriver and that's it.
@user-vm1hi7bo5s
@user-vm1hi7bo5s 2 жыл бұрын
18:10 I did the same thing with a capatitor some time ago, and it zapped me. So, if you ever going to do something like that, better grab it only by 90 degrees side (oh, i mean better don't do this either way). It seems to be thicker isolation there.
@alo1236546
@alo1236546 Жыл бұрын
Could a stepper motor become a cos phi meter
@DanielStingBR
@DanielStingBR 2 жыл бұрын
very nice! Maybe you should give classes!
@edgeeffect
@edgeeffect 2 жыл бұрын
I think we're sitting in his class right now.
@mernok2001
@mernok2001 Жыл бұрын
I think these meters could be made to return the needle to the 1(purely resistive) position when not used.
@weerobot
@weerobot 2 жыл бұрын
Cool...
@jefftheanimal
@jefftheanimal 8 ай бұрын
Valeu!
@jakub3851
@jakub3851 2 жыл бұрын
31:40 wow what a Huge ballast I have a 250w Mercury lamp in the room and can’t imagine how powerful would a 400w sodium one be please make a video about it if you have the bulb
@jackli6889
@jackli6889 2 жыл бұрын
hi,how can i contact to you?
@DiodeGoneWild
@DiodeGoneWild 2 жыл бұрын
danyk at centrum dot cz
@jackli6889
@jackli6889 2 жыл бұрын
@@DiodeGoneWild 🤔
@marlonbayaras2850
@marlonbayaras2850 Жыл бұрын
Now i know why my multimeter is showing strange current reading when in ac, i though the ac current range is faulty as it always shows ridiculously high power reading like when i was testing at 100w powersupply that is drawing 4.6amps at 220v without a load and not even getting warm
@PP-xy9bg
@PP-xy9bg 2 жыл бұрын
Holding a capacitor in each hand directly on the power line. Supeeeeeer dodgyyyy.
@kokotajebka
@kokotajebka 2 жыл бұрын
You have reflected power (from energy stored in your inductor) to power line without compensation.
@gellert-max-nagy
@gellert-max-nagy 2 жыл бұрын
You're truly mad. I understand you know a lot about high voltage, I know a bit myself. I got shocked a few times in my life, I'm sure you tried it too. But when you take a capacitor in your bare hand and touch your syuper dodgy 3 phase setup, my eyes and my mouth opened in disbelief 😮and started laughing. And then you took another one in your OTHER hand and touched it too.🤣
@mernok2001
@mernok2001 Жыл бұрын
Everything up to 1000 volts is low voltage.
@theGraphicAutist
@theGraphicAutist 2 жыл бұрын
The ferrite core looks exactly like the ones used in a microwave oven fan. Is it exactly the same? Id love to make one!
@DiodeGoneWild
@DiodeGoneWild 2 жыл бұрын
It's iron, not ferrite.
@Alchemetica
@Alchemetica 2 жыл бұрын
Most interesting. I would be tempted to remove the cases and display the internals as they have a sculptural technological aspect of a past age or would fit nicely in the set of the film Blade Runner.
@edgeeffect
@edgeeffect 2 жыл бұрын
In England, it seems we only have one phase throughout the whole house. :(
@LMB222
@LMB222 Жыл бұрын
Three phases cost more in subscription fees.
@ketas
@ketas 2 жыл бұрын
now i get how pf and it's correction actually works
@2OO_OK
@2OO_OK 2 жыл бұрын
Is that a price of 10,50 Czech crowns printed on the 200 W Tesla brand bulb?
@DiodeGoneWild
@DiodeGoneWild 2 жыл бұрын
It actually was 10,50 Czechoslovak crowns back then ;)
@rosi6144
@rosi6144 Жыл бұрын
Good explanation. In which country do they speak English like he does?
@dieseltinus6680
@dieseltinus6680 2 жыл бұрын
You forgot to mention: The screws are M3 slotted panhead. You're welcome.
@technixbul
@technixbul 2 жыл бұрын
The STAR on the meter does not show kilovolts, it shows CLASS of ACCURACY the number shows accuracy of one division over the full range of scale
@gelo1238
@gelo1238 2 жыл бұрын
Next: synchroscope xD
@qzorn4440
@qzorn4440 2 жыл бұрын
we have this problem with Rockwell Engineering they sell baseline VFD ac drives then the customer has to troubleshoot the PF and buy all the addon inductors and capacitors to get the PowerFactor close to 1. where in the ero market the drives must be sold as a complete system to keep the power grid clean and lower the reactive power to rid wasted energy. 🤑thanks
@kwinzman
@kwinzman 2 жыл бұрын
What if the current over time is not sinus shaped?
@kwinzman
@kwinzman 2 жыл бұрын
Oh, you answered that around 36:12.
@SigEpBlue
@SigEpBlue 2 жыл бұрын
I think every one of your videos begins with "So...".
@alien8r33d
@alien8r33d 2 жыл бұрын
A worthwhile cautionary tale, but I have to state the obvious: Nobody in their right mind should use one of those cheap multimeters for anything other than low voltage, low current stuff, like Arduino etc, unless they've got a deathwish.
@BobT36
@BobT36 Жыл бұрын
Hahahahha the super dodgeeeee stamp.
@cmuller1441
@cmuller1441 2 жыл бұрын
Hello. I think the inaccuracies with 40W lamp is just caused by gravity. The needle goes down instead of keeping the last measurement. Also after phase swap the needle goes to the same position. Maybe the meter should be mounted horizontally to avoid that.
@cmuller1441
@cmuller1441 2 жыл бұрын
This is what happen when you add a comment while watching a video without waiting for the end...
@AlexanderBukh
@AlexanderBukh 2 жыл бұрын
sjuper, but dodgyy!
@TheSpotify95
@TheSpotify95 2 жыл бұрын
15:39 Super dodgy!!!
@tongxu721
@tongxu721 2 жыл бұрын
Next time frequency meter😆
@j7ndominica051
@j7ndominica051 2 жыл бұрын
These wires look more dodgy than the chinese appliances you criticized. I'd probably short something out from being startled by the spark.
@jeffm2787
@jeffm2787 2 жыл бұрын
Nice, but super dodgy.
@williefleete
@williefleete 2 жыл бұрын
This is what those scam boxes were trying to solve
@justin8894
@justin8894 2 жыл бұрын
More salt!
@attilarivera
@attilarivera 2 жыл бұрын
👏👏👏👏👏 ✌😊👍💚💛💙🇧🇷🇧🇷🇧🇷
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Bluetooth connected successfully 💯💯
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