This macro positioned your object perpendicularly to wire selected.

Macro_Perpendicular_To_Wire.FCMacro

# -*- coding: utf-8 -*-
__title__   = "Macro Perpendicular To Wire"
__author__  = "Mario52"
__url__     = "https://www.freecadweb.org/wiki/index.php?title=Macro_Perpendicular_To_Wire"
__version__ = "00.02"
__date__ = "06/04/2019"

import Draft, Part

try:
    sel = FreeCADGui.Selection.getSelection()                               # Select an object
    
    lineSelected = FreeCADGui.Selection.getSelectionEx()[0].SubObjects[0]   # first object the Path object or SubObjects
    myCircle     = sel[1]                                                   # second object
    
    pointsDirection  = []
    
    pointsDirection = lineSelected.discretize(Number=500)                   # discretize the path line first selection
    
    v=pointsDirection[0].sub(pointsDirection[1])                            # avec vecteurs 1 et 2 (direction debut ligne)
    r=App.Rotation(App.Vector(0,0,1),v)
    
    pl=FreeCAD.Placement()                                                  # placement object
    pl.Rotation.Q = r.Q
    pl.Base = pointsDirection[0]
    myCircle.Placement = pl
    
    del pointsDirection[:]
    FreeCAD.ActiveDocument.recompute()
except Exception:
    print( "Select twoo objects 1:The path 2:The objet to align" )

This macro utility is intended for the use of the program FreeCAD http://www.freecadweb.org/
The icon for your toolbar, it is to place in your macros directory (in the same location of the macro)

Rename in Macro_Perpendicular_To_Wire.png