We have this situation quite often. The Sectionalizer has two terminals so be careful to connect only two line elements to it. Take a look at the following pictures. The users tend to draw the Sectionalizer on top of the pole, but this leads to a mistake, because all 4 lines are then snapped to the Sectionalizer. If you look closer at the first picture you will see the Sectionalizer is disconnecting only the line going west, so what we do is to move the Sectionalizer away from the pole and then to connect it only on both sides with edges:
Seectionalizer-field-picture.png
Seectionalizer-draw-scenario.png