Conductance,Susceptance,Admittance?

[walters]

For parallel circuits:

Does a inductor have conductance?

Does a inductor have Susceptance?

Does a inductor have Admittance?

Does a Capacitor have conductance?

Does a Capacitor have Susceptance?

Does a Capacitor have Admittance?

Why is conductance,susceptance,admittance only for parrallel circuit and not for series circuits ?

Is conductance,susceptance,admittance frequency based?

What does conductance,susceptance,admittance do really?

 

[Zarkabul]

Look, in the first circuit (empedance circuit) the empedance Z = V/ I = R + j(XL - Xc). In here, R is the resitance and (XL-Xc) is the reactance. And the admitance Y = I/V = 1/Z = 1/(R+j(XL-Xc)).
Or look at the second circuit (admitance circuit), in here Y = I/V = G + jB. G is the conductance (1/R) and G is the susceptance (1/XL - 1/Xc).

And inductor has an inductance and a capacitor has a capacitance. Is it clear enough?

 

[walters]

Thanks for the pictures

I got those in my electronics book also but i still don't know what
these terms do really why did they called them different names
if they mean the same thing ?

These terms must "Function" differently?

What are there functions?

 

[walters]

Conductance, susceptance, and admittance are sometimes called the "evil twins" of resistance, reactance, and impedance,


capacitive susceptance (BC) and inductive susceptance (BL).

Take the reciprocal- Why is that to take the reciprocal?

**Whats the difference between Conductance, susceptance, and admittance VS resistance, reactance, and impedance?

 

[zachtheterrible]

**Whats the difference between Conductance, susceptance, and admittance VS resistance, reactance, and impedance?

Conductane is the opposite of resistance, susceptance is the opposite of reactance, admittance is the opposite of impedance I believe.

Resistance reactance and impedance are ways to measure how much a certain device LIMITS current.

Conductance susceptance and admittance are ways to measure how well a certain device CONDUCTS current.

I think I'm right here, but don't go believinng me until someone says that I am :lol:

 

[walters]

Why would they be opposite? because the components are in parrallel
and not in series?

 

[Zarkabul]

To get this event, i must tell you about something. Now, suppose that we have a circuit, N circuit as you can see in the picture. It may contain more than one inputs or outputs, for instance, this circuit has 2 inputs and 2 outputs, this is called as "with 2 gates circuit".

For this circuit (and also for all of the circuits has more than 1 gate) there are 6 six parameters, these are : 1-Empedance parameters [Z matrice], 2-Admitance parameters [Y matrice], 3-Hybrid parameters [h matrice], 4-Transmission parameters [g matrice], 5-Chain parameters and 6- Reverse chain parameters.

1-Empedance parameters (these are matrices) :

| V1 | = | Z11 Z12 | . | I1 |
| V2 | | Z21 Z22 | | I2 |

2- Admitance parameters :

| I1 | = | Y11 Y12 | . | V1 |
| I2 | | Y21 Y22 | | V2 |

3-Hybrid (h) parameters :

| V1 | = | h11 h12 | . | I1 |
| I2 | | h21 h22 | | V2 |

4-Transmission (g) parameters :

| I1 | = | g11 g12 | . | V1 |
| V2 | | g21 g22 | | I1 |

In matrices "1" indicates the first gate (1st input and 1st output) and "2" indicates the second gate (2nd input and 2nd output).

In some circuits the empedance values may be important for you, or Y parameters, or h parameters may be. You can use one of them for the circuit you're analysing, it depends on what you want to do.

For instance, a transistor is modelled as h parameters, cause it has 2 gates (input circuit and the output circuit). You can see it in the 2nd picture. This is a common emitter transistor AC model (or equivalent circuit) for small and middle frequency signals. In here hie's unit is ohm, it's called as "input empedance" [Vbe/Ib, like V1/I1]. hoe's unit is siemens (1/ohm), and it's called as "output admitance" [Ic/Vce, like I2/V2]. hfe and hre are constant, hfe is "forward current gain" [Ic/Ib, like I2/I1]. hre is "reverse voltage gain" [Vbe/Vce, like V1/V2]. These are the specific parameters for a transistor (hie, hoe, hfe, hre) like as "h11,h12,h21,h22".

Also you can consider the capacitance values for the transistor (espacially in higher frequencies). These are inner capacitance of the transistor. But for that (if you consider the capacitance values) you must model the transistor with another model, for instance "pi model". There will be series and shunts capacitors in the circuit equivalent. Here the capacitance (reactance or suspedance) values must be considered.

I wish you understood better now.

 

[walters]

Thanks for helping me out alot

How is this conductance,susceptance,admittance used and measured for DC?


How is this conductance,susceptance,admittance used and measured for AC?

 

[ljcox]

Thanks for helping me out alot

How is this conductance,susceptance,admittance used and measured for DC?


How is this conductance, susceptance, admittance used and measured for AC?

susceptance, admittance are not relevant for DC.

G, B & Y are normally used for parallel circuits since it is easier.

eg. for 2 resistors in parallel, G = G1 + G2. If you did it in resistance, it is R = 1/(1/R1 + 1/R2).

The same applies to reactance/susceptance and impedence/admittance.

for example 2 impedences in parallel Z = 1/(1/Z1 + 1/Z2).

etc.

Len

 

[walters]

So are they the same thing or are they different?

 

[ljcox]

So are they the same thing or are they different?

I don't understand the question.

G = 1/R, B = 1/X and Y = 1/Z.

You use which ever one is convenient for the problem at hand.

Len

 

[walters]

Z(impedance)= R(resistance) + jX(reactance)

Y(admittance)=G(conductance)+jB (susceptance)


Is Impedance the same as admittance?

is Resistance the same as conductance?

is reactance the same as susceptance?

They seem opposite to me like conductance is way different from resistance

Applied:
What is admittance?
1.) applied to a AC circuit in series or in parallel
2.) what is Addmittance mean for a capacitor or inductor

What is Susceptance?
1.) applied to a AC circuit in series or in parallel
2.) what is susceptance mean for a capacitor or inductor

 

[ljcox]

I still don't see why you are having a problem.

They are simply reciprocals of each other as I said in my previous.

So if Z = R + j X

then Y = 1/(R + j X) = (R - j X)/(R^2 + X^2)

So G = R/(R^2 + X^2) and B = - j X/(R^2 + X^2)

Len

 

[walters]

But what does reciprocals mean in this way ? because this is
applied reciprocals


Like a resistor has resistance and conductance

When i put my meter on the resistor i measure resistance how can i
measure the conductance?

A capacitor has capacitance and conductance how do i measure the
conductance from the capacitor?

A inductor has inductance and conductance how do i measure the
conductance from a inductor?


admittance,conductance,susceptance how are these terms applied
to a circuit i never measured these before so i don't know how
these terms affect a circuit or what they do really


admittance what is its function in a circuit?

conductance what is its function in a circuit?

susceptance what is its function in a circuit?

 

[walters]

Whats the difference between Admittance VS Impedance?
1.) A measure of the ability of a reactive circuit to permit current
2.) The reciprocal of impedance
3.) ( Y )


Whats the Difference between Conductance (G) VS Resistance?
1.) The ability of a circuit to allow current
2.) The reciprocal of resistance


Inductive Susceptance (B)(L)
1.) The Ability of a inductor to "PERMIT" current
2.) The reciprocal of inductive reactance


Capacitive Susceptance (B)(c)
1.) The Ability of a capacitor to "PERMIT" current
2.) The reciprocal of capacitive reactance


This is my main problem is this

:Conductance (G) is the reciprocal of resistance:

What does this mean the reciprocal of resistance
What is conductance?
is Conductance
a.) ohms?
b.) what is it really?
Does the reciprocal- mean its the opposite of resistance?

:Susceptance (B) is the reciprocal of reactance:

What does this mean the reciprocal of reactance
What is susceptance?
is susceptance
a.) ohms?
b.) reactance buts its not reactance its a different kind of
reactance but what kind i never measured this for a
circuit im new to this susceptance reactance?

: Admittance (Y) is the reciprocal of impedance :

What does this mean the reciprocal of impedance?
What is admittance
is admittance
a.) ohms?
b.) impedance but what kind is this "admittance impedance"?

 

[ljcox]

But what does reciprocals mean in this way ? because this is applied reciprocals the reciprocal of x is 1/x


Like a resistor has resistance and conductance Yes

When i put my meter on the resistor i measure resistance how can i
measure the conductance? divide the resistance into one or modify the meter to read conductance.

A capacitor has capacitance and conductance how do i measure the
conductance from the capacitor? A cap does not have conductance, it has reactance, the reciprocal of which is susceptance. To measure - apply a voltage and measure the current. X = V/I and B = I/V

A inductor has inductance and conductance how do i measure the
conductance from a inductor Same argument as for Cap above?


admittance,conductance,susceptance how are these terms applied
to a circuit i never measured these before so i don't know how
these terms affect a circuit or what they do really

admittance what is its function in a circuit? It is the constant of proportionality between current and voltage. Y = I/V

conductance what is its function in a circuit? G = I/V

susceptance what is its function in a circuit? B = I/V

You seem to be making this much more difficult than it really is.
See that attachment for an example of how Y, B & G are used

Len

 

[walters]

Thanks ljcox for the information

Is siemens unit measured in TIME because i see mS, uS ?

 

[ljcox]

Whats the difference between Admittance VS Impedance?
1.) A measure of the ability of a reactive circuit to permit current
2.) The reciprocal of impedance
3.) ( Y )


Whats the Difference between Conductance (G) VS Resistance?
1.) The ability of a circuit to allow current
2.) The reciprocal of resistance

Consider Ohm's law V = R I The resistance R is the constant of proportionality between V and I. Now you can transpose such that I = V/R. Or alternatively, you can write it as I = G V. So G is the constant of proportionality between I and V.


Inductive Susceptance (B)(L)
1.) The Ability of a inductor to "PERMIT" current Yes
2.) The reciprocal of inductive reactance Yes


Capacitive Susceptance (B)(c)
1.) The Ability of a capacitor to "PERMIT" current Yes
2.) The reciprocal of capacitive reactance Yes


This is my main problem is this

:Conductance (G) is the reciprocal of resistance:

What does this mean the reciprocal of resistance
What is conductance?
is Conductance The unit of conductance is mho which is Ohm spelt backwards.
a.) ohms?
b.) what is it really?
Does the reciprocal- mean its the opposite of resistance?

:Susceptance (B) is the reciprocal of reactance:

What does this mean the reciprocal of reactance
What is susceptance?
is susceptance The unit of susceptance is mho.
a.) ohms?
b.) reactance buts its not reactance its a different kind of
reactance but what kind i never measured this for a
circuit im new to this susceptance reactance?

: Admittance (Y) is the reciprocal of impedance :

What does this mean the reciprocal of impedance?
What is admittance
is admittance The unit of admittance is mho.
a.) ohms?
b.) impedance but what kind is this "admittance impedance"?

 

[ljcox]

Thanks ljcox for the information

Is siemens unit measured in TIME because i see mS, uS ?

Siemens is the alternative unit for G, B & Y. I use mho as I said in another post.

ms = milliseconds and has nothing to do with Siemens.

However, mS is the abbreviation for milliSiemens.

Units named after people start with an upper case letter, eg. Volt, Ampere, Watt, etc. hence mV, mA, mW.

Len

 

[walters]

mS is the abbreviation for milliSiemens.

but is milliSiemens a TIME measurment?

what is millisiemens really is it time of current or conductance?