My lecture notes about distribution systems/radial schemes say the following:
•In this scheme, feeders radiate from a substation in all
directions and feed distributors at one end only.
• SA is the feeder which feeds the distributor BC at its end B.
The lecture includes the following picture of a radial scheme:
Question: How does this form a complete circuit ? Put differently, the service lines are not part of a circuit as far as I can see.
Best Answer
You are looking at a single-line diagram. Each of those feeders is actually a three-phase AC transmission line.
We draw three-phase circuits as single lines to simplify the drawing, because drawing three parallel lines for every single feeder clutters up the drawing and doesn't convey any extra information.