Conductance spectroscopy of superconducting devices is a common tool for probing Andreev and Majorana bound states. Recently, three-terminal conductance spectroscopy has been investigated because of some limitations of two-terminal ones. In this talk, I will first introduce some basics of conductance calculation of a metal-superconductor junction. Then I will derive the sub-gap conductance matrix for the normal leads in a three-terminal setup and its symmetric decomposition. The relation between the nonlocal conductance and the local BCS charges of the bound states close to the normal probes will be discussed. Finally, an example, a semiconductor nanowire supporting MZM, is investigated in both numerical and experimental methods.[1,2]
 Danon J, Hellenes A B, Hansen E B, et al. Phys. Rev. Lett. 124, 036801 (2020).
 Ménard G C, Anselmetti G L R, Martinez E A, et al. Phys. Rev. Lett. 124, 036802 (2020).