sub panel syst grounding

[Toros]

Hi
About Duplex houses, separate building;

Do in need to bond the one of the sub panel to earth
when it is located inside of house , in the other building ???

I know that I have to bond-to-ground the sub panel of that building
that is located at outside, at the exterior wall.

Thank you

 

[electrofelon]

I don't quite understand the arrangement. Are these two seperate dwelling units and where are the service disconnects?