Like 2FD Sound Services mentioned, when you are talking about volts AC, that usually represents a root mean square (rms) voltage. To convert to peak voltage, you'd multiply by sqrt(2) ≈ 1.414, so that 13 VAC would be about 18.4 V peak voltage across the secondary winding. But in any case, thank you so much for making and sharing all of these videos, across every subject. You're the man!
Thank you. I'm a millwright apprentice. I'm always trying to brush up on electrical theory and formula. My trade doesnt really require a high level of electrical, but why not learn it. You have a great way of making the viewer understand the problems presented
I am somewhat mindblowned by your channel. Because at first I thought you were just teaching a normal science subject. But today I found out that you are also teaching "basic" electricity. Btw thank you for the vids😊😊😊
This video came after my prelim, but I will still use this video to review for my finals. It is great to refresh my studies sometimes. Thanks for the video
very satisfied sir, 10 grade, thank u sir sa pagshare mo ng knowledge sana marami pang video sir, request, ikabit mo na yan power supply sir para makita ang gamit kahit maliit na circuit, sir ganoon pa rin ha ipakita mo ang flow ng current. So much appreciated ty ulit more power.
Thank you for showing flow with arrows like I’m a toddler. Actually helps. Also with the potentials clear up a lot of reasons why certain pieces are placed where. I didn’t pay attention in high school refound my learning bug in college. Starting with zero concepts I believe you did one of the math series I watched as well to refresh.
I really like how he breaks everything down to such a basic level! I hate it when people assume you know too much and then skip steps that leave you baffled...
If you have a secondary of 13vac, normally we are talking about rms. So if we multiply it with 1,41 (root mean square maw) your peak to peak voltage wil be above 18 volts.
Thanks for the lesson. I recently disassembled an electrical device which had components using 120vac, 12vdc, and 5vdc. I couldn’t figure why it had a 120vac to 14vac transformer. After your video I have a much better understanding. I am nowhere ready to put my limited electrical knowledge into practice but with all the devices in today’s world with chips and circuit boards if interesting gaining a little understanding.
Found your video to be really helpful, informative and explained calmly and clearly ! Well Done. I wish i had your level of expertise and the ability to explain a topic as well as you have done here.
Great video...A short on the output side will usually blow the primary side of the transformer. A fuse on the output side will prevent that most of the time. You can easily verify which side of the transformer is blown with a meter to prove it.
A fuse on the primary side is almost invariably what is used. With very small transformers it may not be effective because coupling between the primary and secondary may be poor. I've used transformers rated at between 1 and 2 watts that withstand indefinite short circuiting of their secondary without damage.
isnt the 13 volts at the input to the bridge rectifier an rms voltage and when we place a capacitor to take care of surge current doesn't the capacitor alo eliminate the riple and so shouldn't the voltage be 13 * 2^0.5
Very Good. Alternatively, I believe, you could replace the zener with a Voltage regulator IC(7812) and eliminate the resistor to give the same result result. but great explanation and calculations.
So, when you are barely just getting started learning electronics, you jumped right into IC’s? You’re extremely smart! I haven’t seen your channel. Please share.
@@rprichard8452 He'll no, I'm just a rookie at this. IC 's do have a weakness and an induction coil can serve as a voltage regular proving the values are calculated carefully. Cheers!
Love all your videos, Might I suggest in the near future you go over BJT/FET and MOSFETs? I could definitely use the help! your the man! getting a big donation from me when I graduate in the Spring.
Yes. With PCB-mount transformers with pins that go into holes in the PCB it is quite common to find phasing dots marked on all the windings. With transformers with wire leads you may or may not find such markings. The data sheet is likely to be helpful, but if you don't have that you have to do some testing.
Sr. Jumbo no, I didn’t mean in this example, I mean a transformer operation with no load, why do they generate heat? I’ve noticed some generate much more heat than others. I’d like to see a video on it.
The greater the capacitance, the more energy is stored in the capitor or the electric field of the pontential difference acorss the anode and cathode of the capacitor.
It would be lot more comfortable if you shed some light on what that 13 v really means in a waveform manner, i feel quite a gap between that and how the capacitor actually affects that voltage. You went over that some videos ago and could have brought it up to reduce confusion. Anyway otherwise good video
Yes by using 2 diodes connected to the ends of the transformer secondary winding. The cathode ends of the diodes are connected together. High current twin diodes of 8A to around 30A are available as a single component. The diodes are of a fast recovery or Schottky type.
enjoyed the video. I want to make one of these to run a dc fuel pump. on-line I found an "AC-DC converter 110V 220V 230V to 12V isolated switching power supply board, US". will this handle my project? usually I hook my dc pump up directly to my truck battery but have to keep the truck running to get enough power. thank you for your assistance.
Thank you for such clear explanation. When a zener diode is introduced across the circuit, is there still a need for a load resistor? Will the load resistor not reduce the output voltage? Or is there a zero resistant resistor?
Hi, thanks for the video. I have a question about a fridge inverter for a compressor. It convert 1 phase 120 or 220v~ to 3phase. This inverter is 220v~ and it has coil with these specs 2A/2x5 ,6mH, a full bridge and a cap 220uF/450v and the circuit that generate the 3 phase. My question , when I apply 120 instead of 220 to this full bridge I measure 390V AC and 177v dc across the cap, also across each diode it’s 63v dc. Since I don’t have 220 AC source, my question is what will be the AC/DC voltages across the cap when applying 220v? can I replace the coil so it is compatible with 120v input ? I have a coil with the following spec 4A/2x2,7mH
Hello That was a very informative video and very well explained. Can you guide me in the following question, how do I calculate the value of the capacitor? Regards John
C = Iload / (2 x pi x f x Vripple) where: C is the capacitance in farads Iload is the maximum load current in amperes f is the frequency of the AC input voltage in hertz Vripple is the desired ripple voltage in volts (usually a small percentage of the output voltage)
It is very likely to work OK as far as the power factor correction circuit and downstream circuit goes, however you do have to consider how the PV array will work. Switchmode power supplies all have a "negative input resistance" characteristic - if the input voltage drops, the input current will rise (opposite of what happens with a resistor, where if the applied voltage drops the current does too). This can "collapse" the voltage of a PV array if it is unable to meet the load requirments. I've designed a few switchers with active power factor correction and they would all work fine with DC input as long at it was within the design range (equiv to 85 to 264 VAC for the ones I did).
So basically Rs controls the amount of current let through, the capacitor insures the voltage doesn't decrease too much and supplements the current, the zener diode prevents the voltage from being too great and Rl makes sure the voltage stays within a certain range and the diodes direct the current for the positive cycle and the negative cycle of the alternating current?
I essentially discovered the key aspect of this video by haphazardly trying to bias a transistor. Also could a NTC adjustable thermal resistor be used for inrush ?
220 is European voltage. In the United States the only way you can have 220 is in 2 transformers three phase. Or delta high leg. Usually marked in a the panel as an orange leg or a purple marked legs. Usually found in a three phase panel.
On say a 10 amp 12 volt DC power supply what wattage & resistance would the RS resistor be. Only an electrician and never very good with electronics but somehow managed to troubleshoot & repair a dozen or more 3 phase VFD'S up to 150 HP. YEP good
This video is great, but would it be possible for you to make a video that steps up AC voltage to DC voltage? My friend and I are working on an electrical based school project and that video would help greatly !
Years ago whenever I tried making a 12 or 24 volt DC power supply the voltage was too high. I would use a transformer with a 12 or 24 volt AC output. Only installed a full wave 25 amp rectifier that was laying around. The outputs would be around 17 & 34.bolts so I was afraid of placing a load on it. Understand that voltage does go down a little when a liad is applied. Seem to remember the transformer no load output voltage to be around 13.5 & 27 volts AC.
It's because he made same mistake as you: Your diodes (if Si diodes) took probably 1.4 V down. But when you have 12.1 V AC, peak is 12.1 V x 1.41 = 17 V (1.41 is square root of 2) - for 24 V it's double, of course. This is because: measuring AC voltage (and current) with instrument is measuring of (so called) "effective value" of sin wave Ueff = Umax/1.41. This is cleaver way of measuring - because average is 0 V (half of cycle it is positive and other half it is same but negative).
In forward bias, that is for the condition in which a diode can conduct, the anode is positive with respect to the cathode. In the case of the zener diode, things are different. A zener behaves like an ordinary PN junction diode when the anode is positive with respect to the cathode - it will conduct with about voltage drop of around 0.7 volts (silicon zener; other materials are extremely rare). When used as a zener, it is operated in "reverse breakdown." In that case the cathode is positive with respect to the anode. In general in semiconductor devices, the arrow points in the direction of "conventional current" flow. Conventional current flow from positive to negative. Electron flow is the opposite direction.
DANGER. ELECTROCUTION RISK. FIRE RISK. There is no discussion of earthing. There is no discussion of fuse protection. There is no discussion of safety aspects. There are no warnings included in the video. Strongly recommend - do not use this information as instructions for building to avoid injury or worse. In many countries, building a mains power supply is ILLEGAL, unless licenced to do so. Some of the information is misleading. There is no discussion of RMS vs. DC voltage. The output of a 13V RMS transformer (if available) will produce 13V / 0.707 = 18.388V peak to peak (13 * 1.414 = 18.388V, if you prefer), NOT 13V as stated. Currents and voltages will, therefore, be higher than discussed and silicon diodes will work just fine. A lower voltage output transformer may be considered (eg. ~10V RMS to produce the desired DC voltage and reduce stress on the components). Zeners are better used as voltage references to control other portions of a circuit capable of passing sufficient current (eg. for controlling a pass transistor). An integrated linear voltage regulator (eg. a 7812) contains a zener reference and pass transistor network in a single package). Clamping ~18VDC down to 12VDC via a zener will likely overheat and kill the zener quickly, resulting in either a short (no short protection in the circuit shown) or open (resulting in unclamped 18VDC appearing at the output, damaging the circuit being supplied). Power supply design is potentially hazardous and is a minor art form. Be safe around electricity - it is unforgiving when things go wrong.
I don't believe this video was intended as a 'how to make a power supply' tutorial, rather a *basic* discussion as to what all the parts do and how the circuit functions. While I agree that fuses and earthing are important to safety, they are irrelevant to the function of the circuit and would likely just confuse a learner. If you want to see a video discussing the dangers of building power supplies, make one yourself. There are no part names mentioned in this video, it's clear to see that this is a theoretical discussion. This is exactly how I was taught at university and none of the alumni have been killed building power supplies yet.
If you divide 240V by the desired voltage on the other side, let's say 13V. You would get 18.46 or 18.5. Which is the ratio between primary side of transformer to secondary side. Vp/Vs=Np/Ns. The ratio in the number of turns is the same as for voltage.
Right, he just got outa college and dont know how to apply this on actual equipment so he draws what his textbook says. Jeez thanks, your so much help with drawings but what about real life kid?
As shown, yoiur use of a Zener is not valid. Update this video to show how amperage is controlled while using a Zener. Otherwise, just throw a silicon lienear regulator at the audience.
Woudl be perfect if he also explain How & Why : - To safely isolate 220V-AC part from the low voltage 12VDC part 😂 - To use opto to prevent over-voltage while maintaining the consistency of the current/voltage. - To prevent short-circuit from the components in DC part. - Finally, how to shrink whole board while maintaining great efficiency. 😂 meanwhile all of those can be answered by reverse-engineering cheap PowerSupply made by China wizards.
Final Exams and Video Playlists: www.video-tutor.net/
Like 2FD Sound Services mentioned, when you are talking about volts AC, that usually represents a root mean square (rms) voltage. To convert to peak voltage, you'd multiply by sqrt(2) ≈ 1.414, so that 13 VAC would be about 18.4 V peak voltage across the secondary winding.
But in any case, thank you so much for making and sharing all of these videos, across every subject. You're the man!
Thank you. I'm a millwright apprentice. I'm always trying to brush up on electrical theory and formula.
My trade doesnt really require a high level of electrical, but why not learn it. You have a great way of making the viewer understand the problems presented
How is the apprenticeship going?
@@PunmasterSTP it's busy
@@joehunt3512 I know the feeling, and I hope it's busy in at least kind of a good way...
How does this guy know literally every type of engineering
And science
Is he AI ? Because how can he know about so much and explain it better than anyone 😭
I used to depend on this channel to learn limits and derivates for highschool maths, it seems I can depend on it for college too.
😂he has become so good at everything that whatever he does looks so good 😊
Engineering,I knew him first in biochemistry 😂😂😂
I am somewhat mindblowned by your channel. Because at first I thought you were just teaching a normal science subject. But today I found out that you are also teaching "basic" electricity. Btw thank you for the vids😊😊😊
yeah not basic at all!
This video came after my prelim, but I will still use this video to review for my finals. It is great to refresh my studies sometimes. Thanks for the video
How did your finals go?
very satisfied sir, 10 grade, thank u sir sa pagshare mo ng knowledge sana marami pang video sir, request, ikabit mo na yan power supply sir para makita ang gamit kahit maliit na circuit, sir ganoon pa rin ha ipakita mo ang flow ng current. So much appreciated ty ulit more power.
Thank you for showing flow with arrows like I’m a toddler. Actually helps. Also with the potentials clear up a lot of reasons why certain pieces are placed where.
I didn’t pay attention in high school refound my learning bug in college. Starting with zero concepts
I believe you did one of the math series I watched as well to refresh.
I really like how he breaks everything down to such a basic level! I hate it when people assume you know too much and then skip steps that leave you baffled...
Thanks a lot, i have never gone through such a clear explanation to a circuit in my engineering graduation.
Thanks a lot, I have learned to figure out, what I was nervous for ages with in 30 minutes ✍
If you have a secondary of 13vac, normally we are talking about rms. So if we multiply it with 1,41 (root mean square maw) your peak to peak voltage wil be above 18 volts.
Thanks for pointing that out!
so are we using rms values for the rest of the calculations?
Thanks for the lesson. I recently disassembled an electrical device which had components using 120vac, 12vdc, and 5vdc. I couldn’t figure why it had a 120vac to 14vac transformer. After your video I have a much better understanding. I am nowhere ready to put my limited electrical knowledge into practice but with all the devices in today’s world with chips and circuit boards if interesting gaining a little understanding.
Thank you so much this channel has help me so much
I’m a beginner in electronics and I’m already liking my future 🥰
Found your video to be really helpful, informative and explained calmly and clearly ! Well Done. I wish i had your level of expertise and the ability to explain a topic as well as you have done here.
The most fabulous explanation I ever came across....
Its just something which will really make you love with electronics 😊😊😊
Best explanation about the power supply. Very clear and concise. Thanks
The world's best teacher
Great video...A short on the output side will usually blow the primary side of the transformer. A fuse on the output side will prevent that most of the time. You can easily verify which side of the transformer is blown with a meter to prove it.
A fuse on the primary side is almost invariably what is used.
With very small transformers it may not be effective because coupling between the primary and secondary may be poor. I've used transformers rated at between 1 and 2 watts that withstand indefinite short circuiting of their secondary without damage.
Nice. most explanation videos miss the 0.6 voltage drop and potential difference part.
Excellent justification, fully absorbed.
Explanation was very good and easy to comprehend.
simply a great video. you summarized it very well. thank you.
thank you so much for the explanation it's really helpful
isnt the 13 volts at the input to the bridge rectifier an rms voltage and when we place a capacitor to take care of surge current doesn't the capacitor alo eliminate the riple and so shouldn't the voltage be 13 * 2^0.5
Very Good. Alternatively, I believe, you could replace the zener with a Voltage regulator IC(7812) and eliminate the resistor to give the same result result. but great explanation and calculations.
(No?mm,
I agree. We almost have the same arrangement of our power supply and I use IC7812 as voltage regulator for the output.
@@princecyrillsobrecarey3754 I think the only drawback, is requiring a good heat sink.
So, when you are barely just getting started learning electronics, you jumped right into IC’s? You’re extremely smart! I haven’t seen your channel. Please share.
@@rprichard8452 He'll no, I'm just a rookie at this. IC 's do have a weakness and an induction coil can serve as a voltage regular proving the values are calculated carefully. Cheers!
Love all your videos, Might I suggest in the near future you go over BJT/FET and MOSFETs? I could definitely use the help! your the man! getting a big donation from me when I graduate in the Spring.
Thank you for your time! Very good study.
This video is very helpful.excellent
Thank you.. Clear & Precise
Greate explaining, but I saw alot of power supplies circuits that have a voltage regulator, is it neccessary, and for what use is it?
Voltage regulator acts as a mini step down transformer. It limits the voltage. 9-5v 15 to 7v regulators are available. It has a zener diode inside.
Very well explained! Thank you!
Question: the direction of the current on the secondary of the transformer depends on the winding/polarity right?
Yes. With PCB-mount transformers with pins that go into holes in the PCB it is quite common to find phasing dots marked on all the windings. With transformers with wire leads you may or may not find such markings. The data sheet is likely to be helpful, but if you don't have that you have to do some testing.
Excellently explained
why do I still have some A C voltage at points B and D? Its about half of the voltage before rectifire.
Thanks
Can you do a video explaining why some transformers generate heat?
Id assume heat would be generated from the resistor and the diodes absorbing voltage
Sr. Jumbo no, I didn’t mean in this example, I mean a transformer operation with no load, why do they generate heat?
I’ve noticed some generate much more heat than others.
I’d like to see a video on it.
Excellent vid and channel. What happens to this circuit if the zener diode is not used?
Can we use transformer less supply , buy using current limiting resistor before bridge...if we require at out put is 20 mA.
Thanks a lot!As most of the times saving lives :)
The greater the capacitance, the more energy is stored in the capitor or the electric field of the pontential difference acorss the anode and cathode of the capacitor.
It would be lot more comfortable if you shed some light on what that 13 v really means in a waveform manner, i feel quite a gap between that and how the capacitor actually affects that voltage. You went over that some videos ago and could have brought it up to reduce confusion. Anyway otherwise good video
Thanks for de video!
Is it possible with a center-tap instead of a bridge? 220v to 12v
Yes by using 2 diodes connected to the ends of the transformer secondary winding. The cathode ends of the diodes are connected together. High current twin diodes of 8A to around 30A are available as a single component. The diodes are of a fast recovery or Schottky type.
What explains the .3 v potential difference?
This video helping me so much, its easy to understand.
THANK YOU
enjoyed the video. I want to make one of these to run a dc fuel pump. on-line I found an "AC-DC converter 110V 220V 230V to 12V isolated switching power supply board, US". will this handle my project? usually I hook my dc pump up directly to my truck battery but have to keep the truck running to get enough power. thank you for your assistance.
Thank you for such clear explanation. When a zener diode is introduced across the circuit, is there still a need for a load resistor? Will the load resistor not reduce the output voltage? Or is there a zero resistant resistor?
The load resistor is the thing the power supply is powering... so it is the point of the entire operation ^^
can you please talk about this relation 'Vripple=Idc/RCf'??
Sir, im bit confuse about the stepdown transformer. Thus current will be to high for diodes can handle.? Need help
Very nice presentation!
Hi, thanks for the video. I have a question about a fridge inverter for a compressor. It convert 1 phase 120 or 220v~ to 3phase. This inverter is 220v~ and it has coil with these specs 2A/2x5 ,6mH, a full bridge and a cap 220uF/450v and the circuit that generate the 3 phase. My question , when I apply 120 instead of 220 to this full bridge I measure 390V AC and 177v dc across the cap, also across each diode it’s 63v dc. Since I don’t have 220 AC source, my question is what will be the AC/DC voltages across the cap when applying 220v? can I replace the coil so it is compatible with 120v input ? I have a coil with the following spec 4A/2x2,7mH
Hello
That was a very informative video and very well explained.
Can you guide me in the following question, how do I calculate the value of the capacitor?
Regards
John
I would like that too
hey john,did you ever get to know how to calculate the value of the capacitor.
C = Iload / (2 x pi x f x Vripple)
where:
C is the capacitance in farads
Iload is the maximum load current in amperes
f is the frequency of the AC input voltage in hertz
Vripple is the desired ripple voltage in volts (usually a small percentage of the output voltage)
Thankyou very much for your explanation, I appreciated you spending the time to explain it.
Regards
John
@@sharononejerry1781 Hi Sharon, I was not expecting a reply, this is an excellent answer.
what if I feed an AC active pfc psu directly fro DC solar power if voltage and amp is enough?
It is very likely to work OK as far as the power factor correction circuit and downstream circuit goes, however you do have to consider how the PV array will work. Switchmode power supplies all have a "negative input resistance" characteristic - if the input voltage drops, the input current will rise (opposite of what happens with a resistor, where if the applied voltage drops the current does too). This can "collapse" the voltage of a PV array if it is unable to meet the load requirments.
I've designed a few switchers with active power factor correction and they would all work fine with DC input as long at it was within the design range (equiv to 85 to 264 VAC for the ones I did).
So basically Rs controls the amount of current let through, the capacitor insures the voltage doesn't decrease too much and supplements the current, the zener diode prevents the voltage from being too great and Rl makes sure the voltage stays within a certain range and the diodes direct the current for the positive cycle and the negative cycle of the alternating current?
I essentially discovered the key aspect of this video by haphazardly trying to bias a transistor.
Also could a NTC adjustable thermal resistor be used for inrush ?
220 is European voltage. In the United States the only way you can have 220 is in 2 transformers three phase. Or delta high leg. Usually marked in a the panel as an orange leg or a purple marked legs. Usually found in a three phase panel.
Do you have any videos on class AB amplifiers?
design a power supply circuit that maintain +5v dc output voltage using zener diode .. can you help me with the calculations?
lots of examples on the internet
What is the path of the flow of current here?
Very very nice video good
what wattage resistor should i use if i want to drop the voltage to 4.5 volts?
I want to know why we used e normal resistor in this circuit??
electric hoist has motor winding connected to one side of bridge rectifier to energize brake.
That is so awesome!!! 😮😮😮😮😮😮
Vay canına çok güzel anlattı.
You should put images, other people could never saw a converter.
On say a 10 amp 12 volt DC power supply what wattage & resistance would the RS resistor be. Only an electrician and never very good with electronics but somehow managed to troubleshoot & repair a dozen or more 3 phase VFD'S up to 150 HP. YEP good
What is the difference betwin battery charger and power supply
This video is great, but would it be possible for you to make a video that steps up AC voltage to DC voltage?
My friend and I are working on an electrical based school project and that video would help greatly !
I know this reply is 3 years late, but if you want to step up ac voltage while rectifying it at the same time you can use a cockroft Walton generator
Good.
E Polytechnic. A Technical channel.
(logically) the output of filter should increase ,
what could be the output volts after that increase
If i use ceramic capacitors where can i place it??pls reply
12:37 surge current
Willy nilly jumping around rms and flat dc?
Great video
how about a 24vDC to 120-220vAC with 1-5amp power supply "inverter" circuit? I'll sponsor that video!!
Why we use 4 diodes ?
Need cap. & diod clear for 12 v &5 amp. Thank u
Years ago whenever I tried making a 12 or 24 volt DC power supply the voltage was too high. I would use a transformer with a 12 or 24 volt AC output. Only installed a full wave 25 amp rectifier that was laying around. The outputs would be around 17 & 34.bolts so I was afraid of placing a load on it. Understand that voltage does go down a little when a liad is applied. Seem to remember the transformer no load output voltage to be around 13.5 & 27 volts AC.
It's because he made same mistake as you:
Your diodes (if Si diodes) took probably 1.4 V down.
But when you have 12.1 V AC, peak is 12.1 V x 1.41 = 17 V (1.41 is square root of 2) - for 24 V it's double, of course.
This is because: measuring AC voltage (and current) with instrument is measuring of (so called) "effective value" of sin wave Ueff = Umax/1.41. This is cleaver way of measuring - because average is 0 V (half of cycle it is positive and other half it is same but negative).
You made a mistake. Where the 13V is, it is AC. So, there's no positive or negative until the power passes the diodes.
Okay but explaining this way by each AC half cycle makes things easier.
very good observation
You've saved me
Well explained
Nice video
great ❤️❤️
Thanks man 😊
i think anode is the (-) side and cathode is the (+) postive side
In forward bias, that is for the condition in which a diode can conduct, the anode is positive with respect to the cathode.
In the case of the zener diode, things are different. A zener behaves like an ordinary PN junction diode when the anode is positive with respect to the cathode - it will conduct with about voltage drop of around 0.7 volts (silicon zener; other materials are extremely rare). When used as a zener, it is operated in "reverse breakdown." In that case the cathode is positive with respect to the anode.
In general in semiconductor devices, the arrow points in the direction of "conventional current" flow. Conventional current flow from positive to negative. Electron flow is the opposite direction.
Much have well experiance &intelligent describein well explained thank u only no. &capacity not describer but all is o k
Why channel name is The organic chemistry tutor?
DANGER. ELECTROCUTION RISK. FIRE RISK.
There is no discussion of earthing.
There is no discussion of fuse protection.
There is no discussion of safety aspects.
There are no warnings included in the video.
Strongly recommend - do not use this information as instructions for building to avoid injury or worse. In many countries, building a mains power supply is ILLEGAL, unless licenced to do so.
Some of the information is misleading. There is no discussion of RMS vs. DC voltage.
The output of a 13V RMS transformer (if available) will produce 13V / 0.707 = 18.388V peak to peak (13 * 1.414 = 18.388V, if you prefer), NOT 13V as stated.
Currents and voltages will, therefore, be higher than discussed and silicon diodes will work just fine. A lower voltage output transformer may be considered (eg. ~10V RMS to produce the desired DC voltage and reduce stress on the components).
Zeners are better used as voltage references to control other portions of a circuit capable of passing sufficient current (eg. for controlling a pass transistor). An integrated linear voltage regulator (eg. a 7812) contains a zener reference and pass transistor network in a single package).
Clamping ~18VDC down to 12VDC via a zener will likely overheat and kill the zener quickly, resulting in either a short (no short protection in the circuit shown) or open (resulting in unclamped 18VDC appearing at the output, damaging the circuit being supplied).
Power supply design is potentially hazardous and is a minor art form. Be safe around electricity - it is unforgiving when things go wrong.
I don't believe this video was intended as a 'how to make a power supply' tutorial, rather a *basic* discussion as to what all the parts do and how the circuit functions. While I agree that fuses and earthing are important to safety, they are irrelevant to the function of the circuit and would likely just confuse a learner. If you want to see a video discussing the dangers of building power supplies, make one yourself. There are no part names mentioned in this video, it's clear to see that this is a theoretical discussion. This is exactly how I was taught at university and none of the alumni have been killed building power supplies yet.
Of the same diameter and total length of wires input and output Step down transformer
what is the value of the parts
All people should wear earloop mask when you go out because,of the virus
thank you sir
how to decide capacitor here?
Thanks for sharing sir. Can you give me the component specifications for a 220vac to 12vdc, 15amp power converter. Thanks.
Use Cap to treat Ripple V
Why has he used 13v for the secondary winding when i thought he wanted a 12v outfit?
Output*
Cuz there'll be voltage drops
Why 4 diode instead of 2 diode
can i ask , how about put 240V AC. what the ratio on right side
If you divide 240V by the desired voltage on the other side, let's say 13V. You would get 18.46 or 18.5. Which is the ratio between primary side of transformer to secondary side. Vp/Vs=Np/Ns. The ratio in the number of turns is the same as for voltage.
Um, WHAT????
Right, he just got outa college and dont know how to apply this on actual equipment so he draws what his textbook says. Jeez thanks, your so much help with drawings but what about real life kid?
As shown, yoiur use of a Zener is not valid. Update this video to show how amperage is controlled while using a Zener. Otherwise, just throw a silicon lienear regulator at the audience.
I think you may understand what I say
Woudl be perfect if he also explain How & Why :
- To safely isolate 220V-AC part from the low voltage 12VDC part 😂
- To use opto to prevent over-voltage while maintaining the consistency of the current/voltage.
- To prevent short-circuit from the components in DC part.
- Finally, how to shrink whole board while maintaining great efficiency.
😂 meanwhile all of those can be answered by reverse-engineering cheap PowerSupply made by China wizards.