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Rain Bird E-9 Transformer Replacement: 3-Wire Old vs 2-Wire New

User replacing Rain Bird E-9 transformer. New transformer has 2 wires; old E-9 had 3 wires (two colors). Confused on connection.

Wiring Explanation

Tony: "The transformer should have 2 line wires and 1 ground. Typically the ground wire is green and is tied into the GND terminal on the controller. The other two need to be installed on the adjacent 24VAC terminals."

Ensure the replacement transformer matches the controller's voltage and VA rating. The ground wire is for safety/chassis grounding; the two power wires go to the 24VAC input terminals.

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