How to make an AC Softstarter because my autotransformer keeps tripping my circuit breaker!

28. 03. 2021
140 658 zhlédnutí

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Parts list (affiliate links):
1x Arduino Nano:
1x Push Button:
1x Red & Green 5mm LED:
1x 4N25 Optocoupler:
1x MOC3052 Optocoupler:
1x BTB26 Triac:
1x 5V Power Supply:
1x FBR:
In this project video I will show you why my new autotransformer keeps tripping my circuit breaker and how I built an AC softstarter in order to "softly" start the transformer so that it does not trip my circuit breaker. Along the way we will find out how exactly this problem gets created and how you can fix it easily. BTW, such softstarters are also useful for motors ;-) Let's get started!
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2011 Lookalike by Bartlebeats
Killing Time, Kevin MacLeod
0:00 Showing off the autotransformer
1:04 The problem with the transformer
1:40 Intro
2:13 Functional Principle of an autotransformer
4:27 Finding the problem
5:52 The reason for the problem
7:10 DIY Solution 1 (Simple)
8:15 DIY Solution 2 (Softstarter)
10:33 Final Test & Assembly

  • Seems like I made a rather big mistake in the video. My transformer should not be switched on during the zero crossing point but at the voltage peak in order to decrease the current flow. While recording the current waveforms on the oscilloscope, everything appeared good to me and I am not sure why my circuit breaker stopped tripping when I switched at the zero crossing point. But many viewers pointed me in this direction and after doing research, it seems to be correct. Sorry about this. But if you want to build the softstarter you can still try it out whether it works for you and if not then you can always change the Arduino code in order to switch at a different time point. Sorry again for the inconvenience. I do make mistakes from time to time since this is a one man production. Stay creative :-)

    GreatScott!GreatScott!Před 12 dny
    • @Aks Jindal Because if you plot voltage vs current they are 90 degrees out of phase. So when the voltage is zero (zero crossing) the current is at its maximum. When the voltage is at its peak the current in at its minimum (in theory zero). The circuit breaker trips due to an excess of current. So you want to switch the load when the current is at its minimum to put the least stress on the circuit breaker by having the current ramp up.

      PelDaddyPelDaddyPřed 6 dny
    • Even though (as you have admitted) you erred in the video, the concept appears to be a good one. Great Scott = Great Ideas... :)

      David ChDavid ChPřed 6 dny
    • Great Scott can you make a automatic hand sanitizer machine where people have to pay a quarter dollar to use the hand sanitizer machine.

      Michael HodgeMichael HodgePřed 6 dny
    • Some notes: 1. The current through the transformer should be stopped at zero crossing. Easy with a SCR/ TRIAC. 2. The turn on/trigger of the SCR/TRIAC can be done with a phase shift network. It is not at 90° and can be found by measuring the primary current and adjusting for the lowest peak. This is true for any large transformer application.

      Paul CohenPaul CohenPřed 9 dny
    • If you loaded the output with a resistor, would that not reflect as a resistance to the input so V and I would be in phase?

      Comb FilterComb FilterPřed 9 dny
  • good

    Easy OneEasy OnePřed hodinou
  • Hello, please make a video on how to hot air solder a tiny smd LED to a double sided pcb, I tried using hot air but the LED light keeps burning from how hot the air is

    Its MeIts MePřed 23 hodinami
  • I build very simple, resistor and relay

    Ary YuliantoAry YuliantoPřed dnem
  • Why not a 10ct "NTC 10D-15" and a timer to shorten out the NTC ? Its the only way i can start my table saw.

    Pepe The FrogPepe The FrogPřed dnem
  • Had the same problem with a 1025VA toridoal transformer and even with the SSR it kept breaking the (B16) breaker and this kind of sucks right now Edit: I watched your video and I knew that there was a risk that it wouldn't work, however I still wanted to try it because it would have been so simple

    mistirionmistirionPřed 2 dny
  • a giant capacitor might also have worked

    Westin RitterWestin RitterPřed 2 dny
  • Maybe buying a B curve circuit breaker might be cheaper?

    B_chanB_chanPřed 2 dny
  • How to make this soft starter without using button? For automatic water pump

    LKahfiLKahfiPřed 3 dny
  • Can't I just change the type of the breaker /MCB

    Tech AddyTech AddyPřed 3 dny
  • Hi. How are you? I was watching her videos about li ion and bms. About the BMS HX-3S-01. I see many recommending it, however, some say it is not for charging batteries. What is your opinion? My idea was to put the hx-3s-01, with 3S (2200mAh), and a current limiter of up to 1A and a voltage of 12.6v. It works? I could leave it loading (in the morning) and remove it hours later (because of work and other activities). It's safe?

    Tiago MercesTiago MercesPřed 3 dny
  • i need help what is the value of "brown black gold gold black " on resistor please any one?

    tnt omegatnt omegaPřed 4 dny
  • May you do a "DIY or Buy" of an 12-to-230V-Converter?

    IsanafalkIsanafalkPřed 4 dny
  • I forgot you weren't CNC Kitchen and haven't watched a vid of yours in awhile. Now I have a backlog. Once I get through it I'll probably be getting electronics videos instead of 3D printing videos and have the opposite problem next year.

    KaletheQuickKaletheQuickPřed 4 dny
  • Can you make video about V/I tester ?

    Selahaddin ÇıracıSelahaddin ÇıracıPřed 4 dny
  • Why not include a mechanical relay bypassing the TRIAC at the end of the start sequence? Much less lossy for extended operation.

    M_GargantuaM_GargantuaPřed 5 dny
  • There's an easier way to make a soft start circuit. Just start the load with some resistance in series with it, and then after a time short out the resistance so the load gets the full line voltage. Naturally this could be done manually with a couple of switches or automatically with a simple timed relay circuit. I needed one for my circular saw, to make sure it wouldn't pop my inverter. The one I made was a little bit trickier as I wanted the trigger switch on the saw to instigate the process, without modifying the tool in any way,.

    xanataphxanataphPřed 5 dny
  • hey great scott i am a big fan of you i need some of your help i have seen your video where you made a 5*5*5 led cube with arduino nano so i am asking that i have a arduino uno r3 can i make the same thing with that tell me the wiring with arduino uno and also tell it easy because i am only 12 and from pakistan

    Ahsan AzizAhsan AzizPřed 5 dny

    Syed SaberSyed SaberPřed 5 dny
  • That's rather strange to have the lights go out? The lights here in Australia run on a different breaker, I had a kettle go bad one night which tripped the breaker, the tv and everything else that is plugged into a wall socket was shut down but the lights stayed on! And I was able to see where I was going because in a situation like that, you have to go around turning off the power points until you find what is causing the problem.... Try doing that without lighting at night. Your new variable Autotransformer looks like the one that I got from eBay! Except that mine is RED! And that means it's automatically better than yours LoL, it also has a built-in wall plate that takes any plug from around the world, like the ones that you get as a cheap Chinese adapter but the one used actually feels really good, the plug doesn't fall out and considerable amount of force is needed to plug and unplug.. it also has two carry handles on top which also provide protection for the adjustment knob on the top... But now I'm just bragging LoL 😂

    Peter MilanovskiPeter MilanovskiPřed 5 dny
  • I solved this problem once by using an inrusch current limiter basicly NTC's with a paralel relais

    Gustav PlettigGustav PlettigPřed 6 dny
  • Hi .. Can you pls make a current probe for oscilloscope .. Thank you

    Alaa YousefAlaa YousefPřed 6 dny
  • VEry complicated. Why would a simple resistor and relay soft start circuit not work for you? It works on big power supplies. BYW - you may want to check your breaker in the consumer unit as it may be the wrong type for your circuit.

    Septic SidSeptic SidPřed 6 dny
  • I put an NTC in my Variac to prevent the circuit breaker issue. But this is cool for other reasons!

    PelDaddyPelDaddyPřed 6 dny
  • Great Scott can you make a automatic hand sanitizer machine where people have to pay a quarter dollar to use the hand sanitizer machine.

    Michael HodgeMichael HodgePřed 6 dny
  • you could get some C16 breakers instead of B16 ones

    Szabolcs LőrinczSzabolcs LőrinczPřed 6 dny
  • Hi @GreatScott, I have two questions please. 1) Why is the optocoupler's anode connected via two parallel resistors (R6 and R2) both 220k. Would just one 110k not work? 2) Is the black filament the galaxy black from Devil Design :-) ?

    Claudiu OctavianClaudiu OctavianPřed 6 dny
  • sir, please help me, which charging module is best for 3.7v 500mah LiPo Battery, (the TP-4056 seems unsafe because of 5v/1amp output) or, should i just change the 1.5k Rprog Resistor in TP-4056 to 5k or a10K Resistor for 130-250 mili amp output. Another question: Do i need to use a Charging+protection board if My battery has inbult BMS. also i need to convert the 3.7v battery output to 1.5v (for my wireless mouse) and also i want to keep the size and weight as low as possible, Please help me, I am so confused Thank You

    Vrashabh SontakkeVrashabh SontakkePřed 7 dny
  • Cute bro please make a video on RF circuits theory and how to make a 27Mhz transmitter and receiver 🙏🙏🙏

    HDgaming345HDgaming345Před 7 dny
  • I think you covered all power supplies except linear adjustable power supply ,can you show how you could build one?

    Gentrit HoxhaGentrit HoxhaPřed 7 dny
  • This is absolutely a project that I am going to build. I have a table saw that shakes the whole thing and makes this horrible sound that makes me cringe every time I use it. This project is perfect, and add always, ein weiteres herausragendes Video

    SupertrampSupertrampPřed 7 dny
  • This is why NTC Thermistors are in power transformers in amplifiers

    Sean MayorgaSean MayorgaPřed 7 dny
  • Great

    STHM-20STHM-20Před 7 dny
  • I need one for my fridge. Every once in a while when the compressor turns on the amp draw pulls over 40a but only for a second but long enough to trip the breaker, there after it only pulls 2a. The fridge is only 2 years old.

    Ikannuna PlaysIkannuna PlaysPřed 7 dny
  • why 2 LEDs instead of 1 RGB LED ?

  • please create a subreddit please GreatScott!

  • Honestly, i probably would have suspected that power tower as the cause before anything else

    DigitalIPDigitalIPPřed 8 dny
  • This is why my angle grinder trips my circuit breaker. I have B16 that I want to swap out with one of C25 and make one wall socket for it in my garage. Hopefully this helps in my situation.

    Dave Dörenberg-VeltmanDave Dörenberg-VeltmanPřed 8 dny
  • bc i like doing these kind of things hard once i move to my own place i might just install a softstarter straight in the electrical box

    SparkedPotatoSparkedPotatoPřed 8 dny
  • i didnt think about that in first place i have something does kick braker n i did upgrade braker so doesnt kick braker aging i notice ur video n watch it so that got me learn something new i think it was spike voltage n cause kick back "fire back voltage" to braker that cant handle it but wasnt i see it now ty inform useful things u make is awesome jobs greatscott

    K ZK ZPřed 8 dny
  • The thumbnail made me think it was a pencil sharpener.

    Soul-StruckSoul-StruckPřed 8 dny
  • Isn't that the reason why a lot of systems use an ntc to limit inrush current? But the use of a solid state relais is a nice idea (for my purposes)

    Geert GoossensGeert GoossensPřed 8 dny
  • I've got a 4kVA variac, if I switch it on it's 50:50 whether it'll trip the breaker or not. I use a big 7kVA mains conditioner which soft-starts it and prevents tripping.

    AintBigAintCleverAintBigAintCleverPřed 8 dny
  • i need this every item should do this automaticly

    Thaimachine FilmsThaimachine FilmsPřed 8 dny
  • I’ve faced the same problem with my 10Kw Variac, I’ll try your solutions ASAP, Thanks 🙏

    Eng. Ayman F. El-KhuzundarEng. Ayman F. El-KhuzundarPřed 8 dny
  • so why is this one a "autotransformer" and not a variac ?

    logan grahamlogan grahamPřed 8 dny
  • Hey scott! Can you do a video on P1-ports? Here in Belgium(dunno about Germany) we are getting new digital electricity counters and you can read data from them using a P1-port.

    JasperDGJasperDGPřed 8 dny
  • 6:48 This part is wrong, a transformer should be switched on in the spikes not the zero crossings, this is for both inductive an capacitive loads. An transformer is even worse when switched on the zero crossing point, as it can cause the core to saturate, resulting in a 2-10 current spikes for the full wave

    FerrybigGamingFerrybigGamingPřed 8 dny
  • I'm curious why you didn't just use a thermistor? I'm assuming it's because they wast energy as heat, but Im curious if that's the reason or not

    Alex play's lifeAlex play's lifePřed 8 dny
  • GreatScrott!, I love your videos. But I can't take it any longer that you call it "Auto transformer". Just call it "transformer" or "autobot", don't mix them. Else I'll send out my decepticons

    Markus SchnepfMarkus SchnepfPřed 9 dny
  • haha als wüsste CSworld bzw. Google das ... :D Das erinnert mich an meine SONY AMP (SONY STR-DB783) (max. 290W / 330VA - lt. Manual) Wird über eine Funksteckdose mit dem Rest der Anlage eingeschaltet - bei mir klemmt nichts im Standby, das nicht sein muss. Eigentlich sollte die AMp ja immer am Netz hängen, dann trit das nicht auf (wer keine PV hat bzw. im Winter freut man sich über den unnötigen Mehrverbrauch.) Der 3kW Wechselrichter der PV geht dabei auch mal kurz in die Knie, ein Automat (sind bei einem 3kW WR auch nur SoDa) löst aber nie aus. Die USVs, die noch mal zwischen Netz/PV-Anlage im Wohnzimmer hängen, gehen auch erst mal kurz in Großalarm-Modus :D Scheinbar ziehen die Elkos im Trafo beim Einschalten so viel Energie zum laden, dass das im falschen Vss ordentlich ins Hausnetz schlägt? An eine "Softstart" bzw nen Art "Choke" hatte ich auch schon mal gedacht, naja aber ist halt auch nicht sooo wichtig und weiß nicht, ob die Amp das verträgt. Über nen NE555, oder sogar noch minimalistischer zwei Transen, könnte man eine sehr simple Stufenschaltung (wie beim Stern-Dreieck) realisieren .. Spule oder Widerstand, den dann brücken.. Der Kram ist aber auch schon so lange her ... hahahaha

    A68kA68kPřed 9 dny
  • Will this soft starter work for a solar setup? Starting a motor running off an inverter and solar panels, the startup current is too high and trips the inverter.

    Werner ErasmusWerner ErasmusPřed 9 dny
  • Great project !!! I have (maybe a stupid) question. An Optokoppler contains usually a light enhanced diode (your oc seems to have a transistor). So it lit up when it is powered on. I don't get it, how it triggers the digital input of the arduino with those peaks. Could you close my basic knowledge gap on that point, plaese ? Many thanks for all your great content. I learned a lot and own a cheap & well working fume extractor ;-)

    Andreas GehringAndreas GehringPřed 9 dny
  • I had a similar problem 20 years ago. Solved with a 2kW heater in series with the transformer that was shorted by a relay. It takes some tens of ms for the relay to close the contacts and this time is enough to limit current surge

    Janis AlnisJanis AlnisPřed 9 dny
  • hi scott do ur slow/smoth start work with switch mode power sub. like psu for pc etc? have a sub woffer runing of a psu 1600w to a 2000w amp and it wtrip my breaker 90% of the time 75% one at the time( yes they have BIG capasitor in them) thx for reply ps have 20 amp plugs and 220v ac

    Ante StahlAnte StahlPřed 9 dny
  • 3000 jigawats!? 3000 JIGAWATS?!? GREAT SCOTT!

    shoutitallloudshoutitallloudPřed 9 dny
  • great!

    yunas saxeryunas saxerPřed 9 dny
  • to do softstart just add resistor and switch to baypassit

    Vojta ČVojta ČPřed 9 dny
  • Why not introduce a input resistor and bypass it after a set amount of time. That would not waste power all that much and prevent high inrush as well. Alternatively you could use a MCB with a higher TCC curve.

    Aatir Ehrar SiddiquiAatir Ehrar SiddiquiPřed 9 dny
  • Hi, I hope your doing great videos 👍 I have one doubt My application was I have to monitoring AC Main Voltage and display it using LCD I have designed resistor network in AC main supply and I convert to around 1.7V AC.. It goes to MCU ADC Pin and monitoring it The problem was in that AC voltage I got voltage spike 1. Does it affect MCU 2. How to arrest voltage spike 3. If it is change the Phase Neutral terminal it affect circuit or not? 4. It is correct way to measure or not? 5. Could you suggest some other circuit Kindly please help me 🙏 I was stuck in this concept This is my email ID - Kindly ping me I have to send my CRO voltage spike capture

    balaji rameshbalaji rameshPřed 9 dny
  • why didn´t he use the attiny85?

    Julio BedaqueJulio BedaquePřed 9 dny
  • Thanks for sharing

    EdmorbusEdmorbusPřed 10 dny
  • Hey GreatScott, could you make a video about softstarter for 5V or 12V LED-Strips?

    HeadGameTVHeadGameTVPřed 10 dny
  • You are my inspiration.

    Lucas MoraesLucas MoraesPřed 10 dny
  • Why is this not part of the transformer? Did they even try to plug it in before marketing it?

    gabest4gabest4Před 10 dny
  • I don't know why I persist in watching your videos, I no idea what you are on about.

    SexPestSexPestPřed 10 dny
  • Got a link to where you bought the 3kw auto transformer? My 500w one is a little weak.

    ElliotElliotPřed 10 dny
  • Creative, but I just put an NTC...

    tzok83tzok83Před 10 dny
  • Schöne Schaltung! Ich hatte mir vor Jahren einen Sanftstart mit einem 5Ohm Lastwiderstand gebaut. Dieser wird nach 1s durch ein Solid State Relais überbrückt. Als Zeitgeber dient ein Ne555. Ich benötige die Schaltung für leistungsstarke PA Endstufen. Der reine Nulldurchgang hat alleine nicht gereicht, hatte immer noch Peakströme größer 90A. Du hast echt klasse Ideen, weiter so!

    Sascha SchulzeSascha SchulzePřed 10 dny
  • Great Scott, I love your videos a lot. Your content is on the point with no detours, but you still add all the background information. And I like your visualization style, with pen and paper. It gives me the feeling that I witness you developing the idea in the very moment. Please don't change too much in the future 👍

    André BartelsAndré BartelsPřed 10 dny
  • Variac...

    Marco FranceschiniMarco FranceschiniPřed 10 dny
  • Please can you do "diy or buy a simple 3 phase inverter". I need to run a 3 phase motor cheaply. Cheers

    mondrotamondrotaPřed 10 dny
  • That motor jumped!

    kordtakordtaPřed 10 dny
  • Thanks Boss, good job👍🏻👍🏻👍🏻

    BENNY S officialBENNY S officialPřed 10 dny
  • If you add a potentiometer and a little bit code for the potentiometer, you can control lights to dim and be brighter depending on where you leave the pot knob. Big fan of your work.

    DelaliDelaliPřed 10 dny
  • Need to change my life around!

    The Green ManThe Green ManPřed 10 dny
  • great video bro gonna try it on big vacuum induction motor

    carona variouscarona variousPřed 10 dny
  • Hello mr.scott .. I m ur great fan...can make a video on Bidirectional DC-DC buck boost converter non isolated....for battery charging..I Am not getting proper guidance on it ....

    Sudhir VishwakarmaSudhir VishwakarmaPřed 11 dny
  • Voll gut, dass du das thema mal behandelst. Allgemein cooler channel. Creative buils.

    thementdlthementdlPřed 11 dny
  • Me thinking you could just put a capacitor 😌😅 just like motor

    Dakshesh GaubaDakshesh GaubaPřed 11 dny
  • Much simpler and cheaper solution is using a balast.

    JusstyteNJusstyteNPřed 11 dny
  • very, very bad solution - on heavy load, triac will be overheated. ever best solution is connecting an relay in parallel with triac. when soft-start ended, turn relay on, wait till on, and disable the triac. to "turn off" load, start the triac, turn off relay, wait till relay switching and turn off triac.

    К СК СPřed 11 dny
  • Uhm, iirc a 30cents ntc thermistor in series with your variac would've done the job :-)

    DasIlluDasIlluPřed 11 dny
  • Hi G.S., I had the same problem with a 30KVA autotransformer and the simplest solution was to turn on the circuit with a load applied to the output of the secondary: the large initial current is due to the magnetization current of the primary which is not reabsorbed by the current magnetization of the secondary (output circuit) due to the absence of load. This suggestion was given to me by my service manager (I worked in ENEL) who had worked in a company with a large transformer cabin and who had the same problem, when the softstarters could not be used due to the load (> 4 MVA at 15 KV) and possibly triac, mosfet and arduino did not exist. Try to apply a load to the output (one ohm resistance is fine too: you adjust the output voltage so as not to let it exceed its power) and then power it up: you should no longer fail a ignition P.S. of course the resistor is used only for switching on and must not remain active for all use of the variac. Thanks anyway for sharing the design of a softstarter. P.S. there are modules for universal electric motors, up to 2KWp, very compact (with three wires and automatic, to be inserted in the casings of power tools) on the market, but you would not have made the video :-)

    zola tanaffazola tanaffaPřed 11 dny
  • do analog one

    ElectroBrocoliElectroBrocoliPřed 11 dny
  • Would this implementation switching at peak or zero? be suitable as a soft start for a 500VA toroidal transformer in an amplifier or would just a series resistor and relay to bypass it be a better solution?

    IansMusicalIansMusicalPřed 11 dny
  • You also could change your old B16 Brecker to C16 Breaker

    Yannick _143Yannick _143Před 11 dny
    • Or even c20 or C25. I want to make one wall socket for C25 in my garage so my angle grinder and welder wouldn't Trip the breaker.

      Dave Dörenberg-VeltmanDave Dörenberg-VeltmanPřed 8 dny
  • I had an issue with my laser cutter tripping the circuit breaker when turned on randomly. Depending on when you turn it on/off it can cause a large inrush current. They sell special relays that turn off/on at the peak of the cycle to reduce inrush current. Google "Beware of Zero-Crossover Switching of Transformers"

    J 3J 3Před 11 dny
  • incandescent light switch did not like thermal shock. it's a pretty simple analogue circuit and a great deal easier to understand and less over-engineered than using a microprocessor. The circuit is only hand drawn that I could have photo it if anybody was interested.

    Roderic BickertonRoderic BickertonPřed 11 dny
  • Just use NTC starting thermistor in series, lol

    skorakoraskorakoraPřed 11 dny
  • I was looking to buy something like this about two years ago, but couldn't find any. Our chop saw also has a tendency to trip the circuit breaker. It works more often than not, but since you turn it on and off a lot, it ends up being a problem. Might be time to try something like this. Unfortunately, I don't have an oscilloscope, so debugging would be difficult if things don't work. (And err... I'm not sure I'd dare hook up an oscilloscope to something referenced to mains anyway. Good way to kill your oscilloscope if you don't know what you're doing...)

    YndostruiYndostruiPřed 11 dny
  • Love the project with a practical example built right in

    Tanner NewtonTanner NewtonPřed 11 dny
  • Did you discover photoninduction CSworld channel before? You can see monster version of it

    megrimegriPřed 11 dny
    • This reminded me of photon's videos.

      Derek CDerek CPřed 10 dny
  • Nice project! Thank you for sharing.

    Bill PowellBill PowellPřed 11 dny
  • in industry CB type K are used in this regard . good job dude

    kaakoskaakosPřed 11 dny
  • Awesome built. The last time I dug into this matter, there was a lot of contradicting information regarding if the zero-crossing or the sine peak was the best time to energize the windings. This was due to different opinions about the significance of current lagging the voltage. I never understood that connecting a coil at the zero crossing would instantly make huge currents flow. After watching this video it seems that my gut feeling was right. Connecting at the zero-crossing should induce the smallest amount of inrush current.

    nixxonnixxonPřed 11 dny
    • @JaMoBo265 Thank you for commenting on this. I have wondered about this for so many years without figuring it out. I would like to se a graph representing the current draw when a coil is energised at the different phase angles. Have you ever seen such a graph? 0°, 30°, 60°, 90°, 120°, 150° and 180° would be very illustrating... The rest (180-360°) should be the same, only opposite of 0-180°.

      nixxonnixxonPřed 10 dny
    • @nixxon Correct. Well he simply made a mistake and also corrected himself in the comments.

      JaMoBo265JaMoBo265Před 10 dny
    • @JaMoBo265 Oh no. So it is best to energize a coil at a sine wave peak after all? Then why does this video talk so warmly about energizing a coil at the exact time of mains sine wave zero-crossing?

      nixxonnixxonPřed 10 dny
    • It's not that a coil immediately draws high current when switching on at zero crossing but the current is much higher for the first few cycles until the coil produces enough counter EMF, reducing the current. When switching on at peak of the voltage waveform, the counter EMF is maximum and therefore current rises much slower.

      JaMoBo265JaMoBo265Před 10 dny
  • Lo ve u

    Alex Caceres DiazAlex Caceres DiazPřed 11 dny
  • A whole microcontroller for a simple zero-crossing control task? It seems wasteful to me. Such a scheme for starting a powerful transformer at the moment of current zero crossing is done on a quad op-amp or comparator or even a dual op-amp and on one triac. I saw the start-up schemes when the current passes through zero even in the devices of the mid-1980s.

    Arena engineeringArena engineeringPřed 11 dny
  • How did Humans even managed to figure out all of this?? Wtf?

    Manuel CameloManuel CameloPřed 11 dny
  • Calculate if you can replace your B with a C?

    Ola HansenOla HansenPřed 11 dny