# Capacitor and Inductor in Series

• richardstan
In summary, the conversation discusses the behavior of reactances in a series circuit with a capacitor and inductor connected to an alternating supply. The reactances of the two components are subtracted from each other due to their opposite phases. The formula for calculating the reactance in this circuit is Z=iωL-1/iωC. The conversation also mentions a generator that needs a new capacitor and the details of its specifications. The conversation ends with the speaker admitting to not understanding the formula and being a licensed electrician who needs to refresh their knowledge.

#### richardstan

Hi, if you have a capacitor and inductor in series connected to an Alternating Supply, do their reactances add up?
Thanks
Richard.

Yes, reactance behaves just like resistance in resistive circuits.

Ummm, they add like this 5 & 4 = 1.

Capactitive reactance is 180 degrees out of phase from inductive reactance, so you actually subtract one from the another.

It's good to go back to the definitions. In series,

$$Z= i\omega L + \frac{1}{i\omega C}$$

where $$X_{L}=Im(Z)$$

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I miswrote, sorry. I thought I saw "impedance" instead of "reactance". But why are you considering reactances and not impedances? The former is part of the latter.

I have a generator that needs a new capasitor and I cannot find one any where! can someone tell me what size I need for a kawaqsaki 5.0 ops FA210D modle number: GGK-26-B serile number KJ19-78B
KW: 2.65 Amps:22 KVA: 2.65 Phase:1
voltage: 120 RPM:3600
HZ: 60
would appreciate anyons help!
russhart70
or give me a formula,? PLZ.

Phrak said:
$$Z= i\omega L + \frac{1}{i\omega C}$$
$$= i\omega L - \frac{i}{\omega C}$$

because: 1/i = -i

So, they subtract.

it has been 12 years since i graduated collage, and can't quit understand the formula, I wired two capasitors together and now I am pushing 175 volts out of this generator? cannot rember wat I did?? I am a licenced electrician, and I guess its been to long since I have had to figure this stuff out!

goin to get my books out real quick!

do not understand wat L = wat I know is P=wats I = amps E=volts R=omes

I guess I AM