Why the following connections are not recommended
a. Two inductors in series?
b. Two capacitors in series?


For inductors I know this much that they store current so when you try to break that connection , the rapid drop in current causes high voltages to appear and something burns ... as you see my answer is poor I need to improve it.

All links , answers are welcomed

 

Hello,

I moved the thread to the homework section.

Have a look at the following pages of the eBook:
https://www.allaboutcircuits.com/textbook/direct-current/chpt-15/series-and-parallel-inductors/
https://www.allaboutcircuits.com/textbook/direct-current/chpt-13/series-and-parallel-capacitors/

Bertus

 

b. Two capacitors in series?

Using two capacitors instead of one doubles the cost. Is there anything you gain from using two?

 

Using two capacitors instead of one doubles the cost. Is there anything you gain from using two?

I understood your point but can you look at my point of view?

That thing I wrote about two inductors, I want somebody to explain that to me and I want it to be explained in case of capacitors too....

I tried to look for it on internet but I am not convinced as I didn't get the same type of reason that I have for inductors

 

Hello,

I moved the thread to the homework section.

Have a look at the following pages of the eBook:
https://www.allaboutcircuits.com/textbook/direct-current/chpt-15/series-and-parallel-inductors/
https://www.allaboutcircuits.com/textbook/direct-current/chpt-13/series-and-parallel-capacitors/

Bertus

I don't want to know how to add inductors and capacitors, I want to know why we can't do it ? as in , what bad happens when we connect them and open connection...

 

I don't want to know how to add inductors and capacitors, I want to know why we can't do it ? as in , what bad happens when we connect them and open connection...

Who said it can't be done?

 

I don't want to know how to add inductors and capacitors, I want to know why we can't do it ? as in , what bad happens when we connect them and open connection...

Of course you CAN put them in series. The answer you are seeking is why it's not usually done in practice. I was suggesting you consider the inefficient aspect of using two parts when one might do. For the capacitors, what is the effect on capacitance when you put two in series? What about the required voltage rating of the capacitors?

 

Who is saying not to recommend series caps and series coils? We use them all the time.
Just one example.......a voltage divider.

 

Why the following connections are not recommended
a. Two inductors in series?
b. Two capacitors in series?


For inductors I know this much that they store current so when you try to break that connection , the rapid drop in current causes high voltages to appear and something burns ... as you see my answer is poor I need to improve it.

All links , answers are welcomed

The issue of open-circuiting a current-carrying inductor applies regardless of how many inductors you have (including just one) or how they are connected.

While there might be some technical reasons why two inductors in series have some downsides in practice, I'm not aware of any major ones. Unless you are looking at inadvertent inductive coupling of components, I suspect this is a lower order effect.

But putting capacitors in series has downsides that should be considered whenever it is done, which is not to say that there aren't time when the downsides are acceptable against the benefit from doing so.

At your level of study, one of the apparent benefits of putting capacitors in series is that the maximum allowable voltage across the equivalent capacitance is increased over the ratings of the individual capacitors. But now consider what happens if the two capacitors each of some leakage current associated with them.

 

we can say the basic difference between capacitors and inductors are Capacitors preserve voltage by storing energy in an electric field, whereas inductors preserve current by storing energy in a magnetic field. that 's the differences,,

 

we can say the basic difference between capacitors and inductors are Capacitors preserve voltage by storing energy in an electric field, whereas inductors preserve current by storing energy in a magnetic field. that 's the differences,,

He's not asking about what the difference is between inductors and capacitors. He's asking whether or not it is advisable to two of either of them in series.

 

ohh sorry ,,I think some circuits have capacitors connected in series and parallel combinations.,

 

What happens when a right handed coil and a left handed coil in series is opened?

 

The issue of open-circuiting a current-carrying inductor applies regardless of how many inductors you have (including just one) or how they are connected.

While there might be some technical reasons why two inductors in series have some downsides in practice, I'm not aware of any major ones. Unless you are looking at inadvertent inductive coupling of components, I suspect this is a lower order effect.

But putting capacitors in series has downsides that should be considered whenever it is done, which is not to say that there aren't time when the downsides are acceptable against the benefit from doing so.

At your level of study, one of the apparent benefits of putting capacitors in series is that the maximum allowable voltage across the equivalent capacitance is increased over the ratings of the individual capacitors. But now consider what happens if the two capacitors each of some leakage current associated with them.

I am only concerned with the breaking part and the charged part. When two capacitors are connected in series and circuit is closed, they both get charged... fine ...two capacitors so source voltage can be raised compared to a single one, fine.... what happens when circuit is opened just that I want to know...

Yes but thats the benefit that now more Voltage can be applied... question says why is it not recommended.... by the looks of it, its much more about some transient response....

 

Yes but thats the benefit that now more Voltage can be applied... question says why is it not recommended.... by the looks of it, its much more about some transient response....

But now consider what happens when a DC voltage is applied to the two series capacitors when their leakage current is different.

 

But now consider what happens when a DC voltage is applied to the two series capacitors when their leakage current is different.

what happens?

current flows from 2nd capacitor to first one or something?

 

current flows from 2nd capacitor to first one or something?

And what happens to the voltage across the capacitors if that happens?

 

And what happens to the voltage across the capacitors if that happens?

I am not getting there mate... I am not so good in this .-.

 

And what happens to the voltage across the capacitors if that happens?

Tell me sir, what happens ...

 

I am only concerned with the breaking part and the charged part. When two capacitors are connected in series and circuit is closed, they both get charged... fine ...two capacitors so source voltage can be raised compared to a single one, fine.... what happens when circuit is opened just that I want to know...

Yes but thats the benefit that now more Voltage can be applied... question says why is it not recommended.... by the looks of it, its much more about some transient response....

Consider the scenario I mentioned. Do the analysis.

Do give you something specific, put two 1 uF capacitors that are rated at 50 V across a 75 V DC source. No let's say that one of them has a leakage that can be modeled by a 10 kohm resistor and the other can be modeled by a 100 kohm resistor. After a long time, what is the voltage on each capacitor?