The main disconnect is located in the basement. The distribution panel is on the second floor. Is the copper conductor that runs from the panel to the main disconnect a grounding conductor or a bonding jumper? Should it be #8 copper ? (like the GEC at the disconnect) or can is be smaller?
It sounds as if you are referring to the equipment grounding conductor (EGC) which would be sized according to the size of the OCPD or rated capacity of the remote panel.
**Table 250.122 in the NEC will assist in helping you size them correctly Bill…if you dont have a NEC…always suggest them as a good investment…
Knowlegde is KING !**
and I am a peasant!!!