Glad it was helpful!

Name of software you used ?

Circuit Wizard

excellent analysis!

You're welcome. I'm glad it's useful to you.

Glad it was helpful!

Glad it was helpful!

Thank you too!

You're welcome. Glad to hear that people find the videos useful.

Maybe I should post a new video for 230 VAC supplies as you're not the first person to ask a similar question. Okay, let me think about it first. As for whether the snubber should be parallel with the switch or inductive load, I have always (rightly or wrongly) positioned the RC snubber across the switching element but assumed it could also be placed across the load. Thinking about this further, having the RC snubber across the load is a more direct attempt at protecting the vulnerable component (the switch) rather than across the load (which nonetheless should protect against a large transient). On the other hand, across the load would give the whole circuit protection against transients. Wikipedia and several other references show the RC snubber across the switch. Of course, a diode snubber would have to be placed in reverse parallel across the inductive load.

I found this reference that may be of interest to you - www.bpesolutions.com/bpemanuals/Snubber.pdf Interestingly, they recommend the RC snubber to be placed across the inductive load "for best results" but mention that across the control contacts (the switch) "will also work". It's a shame they don't explain this any further

@@PizzeyTechnology Thanks

Glad you liked it

correct!

50MHz should be fast enough unless the spike is in nanoseconds

Thanks and welcome

It's nice to know my videos are being watched all around the world. Greetings from the UK.

Apologies, I failed to have mentioned that we are pulsing the switch (so transistor say, like a chopper circuit). Then we have rate of change!

Have you added bypass capacitors on your power rails? You may need to do this to reduce noise on the power rails otherwise your microcontroller can be unstable.

I'm glad to help. Thanks for the feedback.

​@@PizzeyTechnology you are my papa btw, this can be the protection for mosfet or any transistor right?

Yes, but best in mind other options exist. For example, a free wheeling diode (reverse biased across the load) if using a DC supply.

@@PizzeyTechnology Yes I’ve use the reverse diode in the inductor. I have to make a boost converter for the fast-charging capacitor circuit, therefore I can't dissipate all the energy on the diode.

Have you seen this article? It gives quite good coverage of how chopper circuits are used. www.kebamerica.com/blog/brake-chopper-circuits-vfds/

No problem, Omid. I'm glad to help.

Thanks, I appreciate the positive feedback.

Good question but I'm always wary in replying to questions or making specific recommendations for circuits that relate to AC mains voltages. I hope that you understand. Have you tried probing the IRQ line with an oscilloscope to see what is going on?

Abu, thanks for your appreciative feedback. Can you post a link showing the actual circuit?

Thanks. It's Circuit Wizard, a program widely used in schools.

@@PizzeyTechnology Will have a look ive heard of livewire and micro cap played with falstad but want something more polished and detailed. Ive used kiCad for basic schematics and pcb layouts.

Thanks. I'm glad you found it useful, and concise!

If the snubber limits the voltage to 50V this may give a good starting point when specifying components. If the snubber works as intended, there would be no high-voltage transients in the circuit. As for the resistor wattage I'll leave that one for you to calculate. It's been a while since I watched this video but hopefully I've given sufficient information.

You can expect the same response. I'm glad that you found the video useful.

No they will not have same response. Please check dv/dt at midpoint of R and C when it is connected in RC and CR fashion. They are different. I am having the same query.

I'm not 100% sure, but I think the capacitor would discharge much quicker. Don't take my words for it. I'm a newb.

In this example I assumed a single coil. There should be no leakage inductance that would be associated with coupling a primary and secondary coil. Is that right?

Of course you are right ! With air coil I meant single coil too. I should have tell it more clearly. Leakage can only occur with two or more coupled coils. It doesn´t make a difference by the way If the medium is air or iron or ferrite as anybodycould think that because of my answer above. Single coil never can or will have a leakage inductance only coupled coils. The medium just changes the leakage value itself.

If in doubt I would pay a trained electrician to do that job. Sorry I could not be of help.

It is not calculated, it is the maximum voltage the switch can withstand

yes, but in this state it will filter only the peak voltages up to the withstand voltage, which in reality may be much higher, in which case the snubber will be insufficient.

@@necipsahin8377 not sure if I understand your point, but in this case, the maximum voltage AFTER filtering will be 50 V, so there is no danger

Yes. For AC usually use varistors (MOV) to clamp the spike. Although it is good idea to install fuse or braker in line, as varistor will drain access voltage to ground/neutral side.

@@commenter5469 Thanks for the information. It is very useful.

Hello Shivm, those are good questions but you may have missed an essential point -- the circuit is capable of raising the voltage above the supply voltage. In the example I chose 50V but I could have chosen some other arbitrary (but acceptable) voltage. The snubber then suppresses the potentially high voltage caused by the inductor. Without the snubber, transient voltages can easily exceed the supply voltage by many times. Does that answer your question?

@@PizzeyTechnology Agreed thanks for the nice explanations.