The Counter on the General Options page of the Electrode Wizard - Design sets the counter number used in electrode names.
By default the counter starts at 1 so the default electrode names are:
You can set the counter to any integer value (or leave it empty) as long as the name string combined with the counter string is unique. If it is not, the counter is incremented automatically until the name and counter combination is unique.
If the counter string is empty, the next value is 2 not 1 because it is generally too confusing to have the second electrode labelled 1.
If you change the name string, the counter is automatically reset to the first unique number for that name. For example, suppose you have the following electrodes in a model.
If extra12 was the name of the last electrode created, the General Options page of the Electrode wizard would display Name as extra and Counter as 13.
If you change Name to trode, Counter changes to 4.
If you change Name to rib, Counter changes to 6.
If you change Name to extra again, Counter changes to 1.
In this last case, the value of Counter is not exactly what we want because we started the names of the electrodes called extra at 10.
We can change Counter to 13 (if we remember where we left off) or 10 (if we only remember that we started at 10).
If we set Counter to 10, an error dialog is displayed telling us that this counter value is already taken and the counter is automatically incremented to the next available value, in this case, 13.