Electro Static line (3D) / point (2D) region
Introduction
The line (in 3D) / point (in 2D) regions are:

either material regions: used to model filiform regions in the study domain

or nonmaterial regions: used to impose boundary conditions (BC) inside or on the frontiers of the study domain
Material regions (filiform regions)
Filiform regions enable the modeling of regions of small crosssection.
The filiform regions are described in the same way as the massive regions, with in addition the crosssection of the region.
In 3D, the direction of the electric field is imposed by Flux. The electric field is usually considered tangent to the line that models the filiform region.
Nonmaterial regions
Nonmaterial regions enable to impose the boundary conditions (BC).
A region…  is a BC that enables one to impose…  It is defined by… 

Perfect conductor  an uniform electric potential and a normal electric field 
an electric potential: floating or fixed value (in V) 
Imposed linear charge  a linear density of electric charge 
a linear density of electric charge (in C/m) (formula with input/output parameters or formula with spatial quantities) 
Imposed electric potential  an electric potential 
an electric potential (in V) (formula with input/output parameters or formula with spatial quantities) 
… on the lines that form the region 