| Problem | Likely Cause | Fix | |---------|--------------|-----| | Fit does not converge | Bad initial guess | Estimate from graph manually | | Negative resistance | Wrong circuit topology | Remove serial R before parallel branch | | CPE exponent >1 | Inductive behavior | Add L element or restrict n ≤ 1 | | High χ² | Missing element (e.g., diffusion) | Add Warburg or Gerischer | | Fit changes drastically with weighting | Data noise | Increase low-frequency averaging |
: The UI is dated and can be finicky on modern Windows OS. zsimpwin tutorial
Have a specific Zsimpwin bug not covered here? Leave a comment below (or on the forum where you found this tutorial). Happy engineering! | Problem | Likely Cause | Fix |
Click "Auto Setup" to let the software estimate initial values. : Chi-Square ( χ2chi squared ) : Look for values in the 10-410 to the negative 4 power 10-510 to the negative 5 power range for a healthy fit. High Standard Error : If an error is Happy engineering
In the parameters table, enter starting values: