- Joined Apr 2, 2015
Since a non-isolated oscilloscope is usually always comparing the input voltage to earth ground, what is the point of having that second lead, at earth potential? It seems like it is just asking for problems if you connect it to a part of a circuit that isn't the same potential as earth ground, while you could just leave it unconnected, or better yet, buy just a single lead without the extra alligator ground clip. Is that second lead just for when you isolate the oscilloscope from earth ground? If so, why does it come standard with two leads when the standard oscilloscope is earth grounded?