$basebias

$basebias is to determine the additional bias in the simulation.

It is similar to the $sourcebias, where is a fixed value is used. This is for the system that has 4 or more contacts.

For example

$basebias
0.1 

This means that the bias of the base contact is at 0.1V.

The $basebias setting in GUI interface is here
Press Contact Setting and set the V-base field, remember to check the box below!