Simulating capacitor charge times SOLVED

Does CircuitLab somehow ignore capacitor charge times? I made a very simple circuit charging a 1000uF capacitor with a 9v battery through a 3k resistor and it shows it instantly being fulling charged. Using T = 5RC as the amount of time to (approximately) fully charge the capacitor, is should take 15s.

Here is the circuit: https://www.circuitlab.com/circuit/6f7mjpfpwy9f/capicator-charge-time/

by trevorsmedley
January 25, 2020

The problem is the capacitor starts out charged up. Put a time controlled switch to discharge the cap, and open it at t=0. Like in:

(Yes, that's kind of weird)

by wdbarker3
April 07, 2020

Dealing with this sort of problem (finding a time constant) I generally use a square wave generator rather than straight dc. This gives an indication of both the initial transient and the steady state if you let it run long enough

by Foxx
April 09, 2020

Great idea. I was just trying to give the OP the picture he requested, but showing him more is better.

by wdbarker3
April 09, 2020

Thanks for the info guys (although, wdparker3, your image doesn't seem to be showing up for me).

by trevorsmedley
April 13, 2020

That's odd. I just now made it public. See if it's there now. I would expect a post of a private circuit to work, but maybe not. This site is not long on documentation.

by wdbarker3
April 13, 2020

It's there now! Thanks!

by trevorsmedley
April 13, 2020

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