Stjerne-til-trekant transformation

$$R_{12}=\frac{R_{10}\cdot R_{20}+R_{20}\cdot R_{30}+R_{30}\cdot R_{10}}{R_{30}}$$

$$R_{23}=\frac{R_{10}\cdot R_{20}+R_{20}\cdot R_{30}+R_{30}\cdot R_{10}}{R_{10}}$$

$$R_{31}=\frac{R_{10}\cdot R_{20}+R_{20}\cdot R_{30}+R_{30}\cdot R_{10}}{R_{20}}$$

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Trekant til stjerne transformation

$$R_{10}=\frac{R_{12}\cdot R_{23}}{R_{12}+R_{23}+R_{31}}$$

$$R_{20}=\frac{R_{12}\cdot R_{31}}{R_{12}+R_{23}+R_{31}}$$

$$R_{30}=\frac{R_{23}\cdot R_{31}}{R_{12}+R_{23}+R_{31}}$$

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