Fatal Exception for tetrahedra construction. "Cannot place a volume inside itself!"

When there are building Box or Tube geometry solid the parameter G4ThreeVector() in function G4PVPlacement() means position of geometric center of Box or Tube. What means it for Tetrahedra ? For example I create the next solid:

G4ThreeVector anchor = G4ThreeVector(0, 0, 3);
G4ThreeVector p2 = G4ThreeVector(-1, 1, 0);
G4ThreeVector p3 = G4ThreeVector(1, 2, 0);
G4ThreeVector p4 = G4ThreeVector(1, -1, 0);
G4bool* degeneracyFlag = nullptr;
G4Tet* Sb_solid = new G4Tet(“Sb”,
anchor,
p2,
p3,
p4,
degeneracyFlag);

When I set in G4PVPlacement() value of position equals to G4ThreeVector(0cm, 0cm, 0*cm) there appears Fatal Exception with message that: “Cannot place a volume inside itself!”. Which are the right values of postition ?

I doubt that error has anything to do with position. Perhaps you are specifying the LV as the mother volume of its own placement. That’s obviously wrong, and would generate exactly the error you quote.