# Need help with pspice

#### count_volta

Joined Feb 4, 2009
435
Hello, I am new here. I was not sure where to post this. I'm very happy that I found this site. I adore electronics, and am in University right now with electrical engineering as a major. I have a question about pspice. I made this circuit.http://img339.imageshack.us/img339/4773/cbnqo8.jpg The voltage source is 24cos(20t+45°) volts. I would like pspice to tell me the voltages and currents as it is doing in the above screenshot, but for some reason its giving me 0 everywhere. I used a VAC and have a phase shift of -90 to change it into a cosine. The magnitude I put in is 24 which is not RMS but the actual peak magnitude, but I can fix that. I also tried using a Vsine source where I can enter the frequency f= 20/2pi hz It still gives me zeros everywhere. I am trying to analyze the circuit at steady state, meaning when the transient part dies out.Why is pspice giving me zeros? BTW If I switch the source to a DC source, it gives me correct voltages and currents.I am very new at pspice, can anyone help? Thanks.

#### n9352527

Joined Oct 14, 2005
1,198
What kind of sweep are you using? Can you post you analysis settings? And the netlist?

#### count_volta

Joined Feb 4, 2009
435
I am using bias point detail. No sweep.

* Schematics Netlist *

C_C2 $N_0001$N_0002 .004
R_R2 $N_0001$N_0002 40
R_R4 $N_0001$N_0003 25
L_L2 $N_0003$N_0004 4
L_L3 $N_0002$N_0005 5
L_L1 $N_0006$N_0005 2
R_R1 0 $N_0006 15 R_R3$N_0005 $N_0004 20 C_C1$N_0004 $N_0007 .005 L_L4 0$N_0007 3
V_V5 \$N_0001 0 DC 0V AC 24 -90

#### eblc1388

Joined Nov 28, 2008
1,542
Why is pspice giving me zeros?
If you connect a DC ammeter in series in places where you want to measure AC current, would the actual AC current gives you any readings other than zero on a DC ammeter?

If you want steady state current waveform, my way is to use a longer transient period so that the transient have all die down and steady state results.

There might be a better way to do it but I'm a novice too.

#### n9352527

Joined Oct 14, 2005
1,198
You can't use bias point with AC. Either use AC analysis, which won't give you all the necessary VI, or as eblc1388 said above, use transient analysis with long enough time.

#### termus

Joined Mar 14, 2009
4
the zeros you see are dc values. You have an ac source, so if you want the ac values at different parts of the circuit follow the following
1. put a probe where you want to see the ac voltage (voltage/level marker)
2. go to 'edit simulations settings' and in the analysis type drop down menu select time domain (if you want the time domain) or select the ac sweep/noise (if you want the frequency domain)
3 arrange the 'run to' or frequency values
4 click on the simulate button and you should see the simulation.
Its only as a simulation that you can see the ac values.