Incorrect Orientation of the Current Transformer

  1. Locate the CT(s) used to measure the source that is displaying incorrect power flow readings.
  2. Verify the CT(s) are oriented such that the label is facing toward the source (away from the breaker).
    1. Solar Current Transformer: Label toward the Inverter
    2. Site Current Transformer: Label toward the Grid
Figure 1. Tesla 100 A Current Transformer Orientation in Relation to Power Flow
Figure 2. Neurio W2 CT Correctly Oriented to Measure Solar (top) and Incorrectly Oriented (bottom)