Hi @bob1951, the case analyser is mainly to take the heat produced by charging in to account and stop it derailing the refinement. Not essential but nice to have, the mod resistance and the battery Watt hours are far more important, if the battery bar is out then a battery analyser curve is a good idea.
To measure the Mod Resistance you need to short the 510 while running atomiser analyser, I got best results with a cartomiser I soldered, but a solid copper bar was almost as good. Details:
Mod Resistance - DNA 200 Early Adopters Forum
For the battery analyser you can make some large loops with thick kanthal in a dripper that will stand running at 40 W, this is in a velocity with 0. 5 mm