Negative Site Reading

On the landing page, the site value is negative. An alert will appear on the landing page

Steps to Troubleshoot

Confirm the CTs are facing the correct way:
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)
Confirm the CTs are measuring the correct phase:
1. Locate the CT on the Meter page in Tesla One.
2. Determine which phase the CT should be measuring.
  Note
  If using Gateway CTs, the ports are CT 1 (Line 1), CT2, (Line 2), CT 3 (defaults to Line 1 but can be configured as Line 2 in Tesla One).
  Note
  If using a Neurio meter, the ports are A (Line 1), B (Line 2), B (Line 2), A (Line 1) and are determined by voltage reference.
3. Verify the CT is measuring the correct phase.
  Figure 3. Gateway CT Measuring Correct Phase (top) and Incorrect Phase (bottom)
  Figure 4. Neurio W2 CT Measuring Correct Phase (top) and Incorrect Phase (bottom)
  Note
  In the examples above, the CT is monitoring a solar inverter conductor, which is why only (1) CT is required.

Note

The site value can be negative if power is flowing to the grid.