open circuit measurments return Nan

[Guy04]

In using the DMM 4070 I"ve noticed that in 2-wire resisitance mode, If I set the range to be smaller than the actual measured resistance I get back a "nan".  I've also noticed that if I'm making measurements to verify open circuits I also get a "nan" back sometimes and sometimes is a huge resistance value. 

Is there any way to distinguish between the two?

[Elijah_K]

When measurements are outside of the range of the 4070 it will return 'NaN.'  In your case, there is no way to distinguish between two different resistances if they are both beyond the range of the DMM card.