Does having low ESR, doesn't this change the charge time or discharge time?

 

But that's good to have a low ESR? Right

Well yes - but its rather irrelevant when you have a 100R resistor in series.

There is also some possibility of increased leakage resistance with multiple electrolytics in parallel.

 

A quick search on Google turned up the following

Equivalent series resistance - Wikipedia, the free ...

en.wikipedia.org/wiki/Equivalent_series_resistance‎Wikipedia


Jump to Capacitors - Capacitors[edit]. In a non-electrolytic capacitor and electrolytic capacitors with solid electrolyte the metallic resistance of the leads ...‎Overview - ‎Component models - ‎See also - ‎References

Since we are talking a internal resistance inside the capacitor, what do you think?

 

So having high or low ESR, changes the time constant formula RC = T, having low or high ESR changes R TOTAL

 

Ok from another thread I have been asked to ask you this Dexter.

ARE these drawings from part of a airplane or airplane system or not? .

You may have to wait for the book to come out, we must be approaching the deadline with the amount of content so far.
Max.

 

So having high or low ESR, changes the time constant formula RC = T, having low or high ESR changes R TOTAL

In high current pulse applications like SMPSU, ESR can be dead critical - but in a CR timing network where R is in hundreds or thousands, it would have to be a pretty bad capacitor to even exceed the standard tolerance of a resistor.

By the time a capacitor had deteriorated that bad, its probably lost a fair chunk of its capacitance as well.

 

In high current pulse applications like SMPSU, ESR can be dead critical

Why only in high current pulse applications? so the voltage and current have to be really HIGH for ESR to be added

Why doesn't low current or low voltage have an affect on ESR?

 

Electrolytics in parallel also give a lower net ESR than a single cap - but that's hardly likely to be the issue with a 100R resistor in series with the parallel combination.

What value of resistor in series would be make ESR as issue?

 

Your missing the point. Where the capacitor is part of a power supply any resistance is an issue, especially where you may have several amps involved. If a cap has an internal resistance of 0.1 ohms and it is providing 5A then there will be a drop of .5VDC inside the capacitor, and it will disapate 2.5W (not an insignificant amount of heat).

The lower the ESR the better.

 

well the RC network has 3 caps in parallel that is an RC time network that goes to a Solenoid coil

I'm not sure if this is high current or high voltage, but maybe they didn't want a voltage drop across the capacitor

Because I know that the solenoid won't work when there is a lower voltage

Plus this RC network is BEFORE the solenoids coil, which supplies the coil voltage and current to get turned on

The RC network is used so that if there is a power shut off momentary the 3 caps keep the voltage and current STORED and the ESR is very low to not cause an added time delay or add to the R total

Does having parallel caps help STORE voltage and current more VS just having One cap at the same value?

 

Does it take "longer" for 3 caps to discharge the voltage and current VS 1 cap rated at the same capacitance value?

 

T=RC. Can you guess what the answer will be?

 

so it's all about getting that capacitance value when you add 3 caps together?

Guys, I think you are all being "Played".

 

No,

the way i'm looking it is

One cap = like a stored battery
3 caps = like 3 stored batteries

It takes longer for 3 caps to discharge the stored voltage VS 1 cap

 

Then you are looking at it wrong. You need to compare the effective value of the three capacitors to a single capacitor having that same capacity. What does T=RC do for you then?

 

So adding 3 caps in parallel doesn't triple the storage? the capacity stays the same value

 

I really don't see the confusion factor. Three caps in parallel... ADD the individual values for a total. That total COULD be replaced with a single capacitor of that total value. You do know how to add microfarads together, don't you. If I have four 250uF capacitors in parallel, they could be replaced by a single 1000uf cap. Does that clear it up? If not, I don't know how to help any more.

 

That's why they use multiple caps in a power supply using the same value cap, it's to keep storage

The more caps in the power supply , the more storage

 

Looks like we're looping. Goto post 1 and start reading!

 

Hello Dexter,

Have a look at the following page:
http://www.physics.sjsu.edu/becker/physics51/capacitors.htm

This is one of the many pages about capacitors on the EDUCYPEDIA:
http://educypedia.karadimov.info/electronics/capacitors.htm

Bertus