High-leg Δ (also known as wild-leg, stinger leg, bastard leg, high-leg, orange-leg, red-leg, dog-leg Δ) is a type of electrical service connection for three-phase electric power installations. It is used when both single and three-phase power is desired to be supplied from a three phase transformer. The three-phase power is connected in the Δ configuration, and the center point of one phase is grounded. This creates both a split-phase single-phase supply (L1 or L2 to neutral) and three-phase (L1–L2–L3).
In this case, the voltages are as follows:
Between phases 240V;
Between split-phases and neutral 120V;
Between high leg (L3) and neutral 208V.
Flip on the SPST switches to turn on primary high voltage.
Switch between the voltmeters to see the different voltages.
