Hello,

I am stepping through a tutorial on series RLC circuits located here:

http://www.electronics-tutorials.ws/accircuits/series-circuit.html

and am trying to simulate the simple RLC circuit displayed. The tutorial (and my calculations) state that there should be roughly 5.14A running through this circuit, however my SPICE simulation states that the max current drawn is 4.9A (see attached). I verified that all of the parasitic values for the source, capacitor, inductor, and resistor are set to 0. What am I missing here?

 

hi met,
Please post your LTS asc file so that we can compare results.
Eric

 

I get the same 5.14 A as the peak current. You are looking at the waveform well enough along so that any transients should be long dead.

It looks like you don't have a lot of samples near the peaks, so you might try reducing the time step on the transient simulation and see if that makes a difference.

 

Set the Maximum Time Step to 1u and you'll get closer to the theoretical value.

 

Set the Maximum Time Step to 1u and you'll get closer to the theoretical value.

I get the same 5.14 A as the peak current. You are looking at the waveform well enough along so that any transients should be long dead.

It looks like you don't have a lot of samples near the peaks, so you might try reducing the time step on the transient simulation and see if that makes a difference.

Yep! This was the problem! I decreased the stepsize by two orders of magnitude, and now I see the theoretical numbers! Silly mistake. Thank you all!

 

Not really a mistake: just one small part of the learning curve .