PSpice TLOSSY Parameters

[Bob Penoyer]

The TLOSSY transmission line has these parameters:
LEN - Electrical length
R - Per unit length resistance
L - Per unit length inductance
G - Per unit length conductance
C - Per unit length capacitance

All of these are clear to me except G. Since there is an R, what is
the purpose of G? My guess is that G is the conductance per unit
length between the center conductor and the shield. Correct?

PSpice objects when G is 100 or more times larger than C, so it
appears that PSpice is looking for a small number, i.e., a high
resistance. That's why I reached the conclusion stated above.

 

[Helmut Sennewald]

"Bob Penoyer" <bob@NOSPAMbobpenoyer.com> schrieb im Newsbeitrag
news:2p09765nt742n3vov8ukk5263kog8f6r07@4ax.com...

The TLOSSY transmission line has these parameters:
LEN - Electrical length
R - Per unit length resistance
L - Per unit length inductance
G - Per unit length conductance
C - Per unit length capacitance

All of these are clear to me except G. Since there is an R, what is
the purpose of G? My guess is that G is the conductance per unit
length between the center conductor and the shield. Correct?

PSpice objects when G is 100 or more times larger than C, so it
appears that PSpice is looking for a small number, i.e., a high
resistance. That's why I reached the conclusion stated above.

Hello Bob,

G is the conductance between the center wire and the shield.

Best regards,
Helmut

 

[Jim Thompson]

On Tue, 24 Aug 2010 19:50:50 -0700, Bob Penoyer
<bob@NOSPAMbobpenoyer.com> wrote:

The TLOSSY transmission line has these parameters:
LEN - Electrical length
R - Per unit length resistance
L - Per unit length inductance
G - Per unit length conductance
C - Per unit length capacitance

All of these are clear to me except G. Since there is an R, what is
the purpose of G? My guess is that G is the conductance per unit
length between the center conductor and the shield. Correct?

Yes.

PSpice objects when G is 100 or more times larger than C, so it
appears that PSpice is looking for a small number, i.e., a high
resistance. That's why I reached the conclusion stated above.

The dimension of C is Farads, per unit-length

The dimension of G is mho's (reciprocal of Ohms), per unit-length

If the conductance (resistive) is more than the effective conductance
of the capacitance you'd have a pretty bad line

...Jim Thompson
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