Strong Acid with a Weak Base, example for sulphuric acid along with dilute ammonia:
Initially the conductance is high and then it decreases because of the replacement of H+. But after the endpoint has been reached the graph becomes almost horizontal, because the excess aqueous ammonia is not appreciably ionised within the presence of ammonium sulphate in below figure.
Figure: Conductometric titration of a strong acid (H2SO4) vs. a weak base (NH4OH)