This document discusses delta-star and star-delta transformations for electrical networks. It provides the formulas to calculate resistances between points in a delta or star network given the individual resistances, and vice versa. The key formulas are:
1) Resistance between any two points in a delta network can be calculated from the other three resistances.
2) To transform from a delta network to a star network, the individual resistances in the star are calculated using the formulas provided.
3) Similarly, the individual resistances in a delta network can be calculated from the resistances in a star network using the formulas.
