RE: Capacitor - series?

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Original poster: "Luke" <Bluu-at-cox-dot-net> 

Good point
Never thought of it that way.

Luke Galyan
Bluu-at-cox-dot-net

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Saturday, February 07, 2004 10:19 AM
To: tesla-at-pupman-dot-com
Subject: RE: Capacitor - series?

Original poster: "Randy & Lori" <rburney6-at-comcast-dot-net>

I don't think this will work.  Without the math lets try this logically.
If there is a large cap and a small cap in series, current will only
flow as long as it takes for the smallest cap to charge.  Once the small
cap is charged, no more current will flow.  If no current is flowing,
the larger cap cannot continue to charge.  Both caps will always charge
to the same voltage no matter what the voltage rating (or size) of the
two caps.  Current does not flow through a capacitor, and all of the
electrons that are used to charge the large inside plate of the large
cap are coming from the inside plate of the small cap.  Because of this
you need to figure the equivalent capacitance before attempting to
figure reactance.

Randy
Savannah, GA

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, February 06, 2004 8:41 PM
To: tesla-at-pupman-dot-com
Subject: RE: Capacitor - series?

Original poster: "Luke" <Bluu-at-cox-dot-net>

I am no guru but I don't think they would see 5KV each.
The example used was:
1 nf 10 kV cap and a 10 nF 1 kV cap.
If we assume a voltage of 10KV and a frequency of 60HZ we can:
1. Calculate the reactances of the caps at 60HZ:
	1 nF = 2,652,582 Ohms
	10 nF = 265,258 Ohms

2. Add these two resistances in series
	2,652,582 + 265,258 = 2,917,840 Ohms

3. Use ohms law to calculate the current flowing through the series
circuit.
	10KV / 2,917,840 Ohms = 3.4mA

4. Apply ohms law to each cap to see the voltage across it.
	1 nF = 2,652,582 Ohms
	2,652,582 Ohms * 3.4mA = 9KV
	10 nF = 265,258 Ohms
	265,258 Ohms * 3.4mA = 900V

The 1 nF will see 9KV and was rated at 10kv it should be ok without
taking over rating into account.

The 10 nF will see 900V and was rated at 1KV so it should be ok as well.

The two caps will not see 5KV each.  They will see the voltages above.

Hope this helps.
Feel free to correct me if im off.


Luke Galyan
Bluu-at-cox-dot-net

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, February 06, 2004 3:34 PM
To: tesla-at-pupman-dot-com
Subject: RE: Capacitor - series?

Original poster: "Randy & Lori" <rburney6-at-comcast-dot-net>

Stacking in series will give you the calculated capacitance (the
reciprocal of the sum of the reciprocals), but the voltage rating will
not work like you are thinking.  If you have 5 capacitors rated at 2KV,
you can stack them for 10KV because what matters is the difference of
potential felt on each lead of the individual capacitors.  If you were
to read voltage between each of the five caps you would find 2KV.  In
the case you describe, the max voltage that you could apply would be
2KV.  If you were to ally 10KV to your caps, they would "Feel" 5KV each.

Randy
Savannah, GA

-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Friday, February 06, 2004 1:59 PM
To: tesla-at-pupman-dot-com
Subject: Capacitor - series?

Original poster: Kreso Bukvic <kreso.bukvic-at-kc.htnet.hr>

Can we series caps that are diffrent in working voltage and capitance?
Example if we have a 1 nf 10 kV cap and a 10 nF 1 kV cap? If i series
them
il get 11 kV capacitor? What will happen with capitance, will this work?