At Emporia Energy, we strive to help you manage your energy usage effectively. One common issue our Customer Support team encounters is inaccurate measurements from the Current Transformers (CTs) used with the Vue Gen 3 energy monitor. This article will guide you through troubleshooting these measurement discrepancies.
Note: This article addresses issues related to inaccurate measurements from the CT's. If your circuit/CT is not appearing in the Home screen circuit list at all, please refer to this article.
Types of Circuits and Corresponding CTs
200A CTs:
The 200A CTs are plugged into the top of the device and their measurements are combined when viewing the Watts unit within the app. The most common issue with 200A CT measurements is an incorrect number of CTs for the system's phase count. Ensure you have one 200A CT attached to each live main line as follows:
Single Phase Systems: Require one 200A CT.
Single-Split (Two) Phase Systems: Require two 200A CTs.
Three Phase Systems: Require three 200A CTs.
Troubleshooting 200A CT Issues:
Verify Placement: Ensure the 200A CT is on the live mains, not on neutral lines.
Check Multipliers: Do not use multipliers on the "mains" circuit within the app. The Vue Gen 3 measures voltage directly and adjusts for 240V or 120V systems automatically.
Correct Circuit Placement: Place the 200A CTs on the system mains, not branch circuits, as the Vue Gen 3 assumes all CTs in the top ports are for mains monitoring.
Solar/Generation Systems: Ensure the 200A CTs are positioned upstream from the inverter's incoming lines. Detailed solar/generation tracking information is available here. If your device is not displaying Net Usage (or Net Production) at the top of the Home screen and only displaying Total Usage (as the top line item) - then you'll want to reset the device to track solar correctly.
Switching to the Amps unit of measurement within the app can help troubleshoot mains/CT issues by displaying each sensor's behavior separately.
50A CTs:
Troubleshooting side sensor accuracy can be challenging. Here are common steps to resolve issues:
General Steps:
Single Line Monitoring: Ensure the 50A CT is monitoring only one line. If using a multiplier, temporarily remove it and add another 50A CT to the other line for direct measurement before troubleshooting.
Separate Wires: If multiple wires are run through a single sensor, separate them temporarily for direct measurement.
Sensor Not Showing Usage:
Correct Line and Port: Verify the 50A CT is on the correct line and plugged into the appropriate port. Check the port number on the back of the Vue 3.
Breaker Test: Flip the breaker for the appliance load while running it. Does the appliance turn off? Are the 200A CTs seeing the same behavior but missing from the 50A CT measurement?
Neutral Line Check: Ensure the 50A CT is not around any neutral lines or covering multiple wires on different power phases.
Duplicate Sensor Test: Add another CT to the same line to see if measurement behavior is duplicated. Consistent measurements indicate device and sensor functionality. Inconsistent behavior may require testing on another line to identify discrepancies.
Sensor Inaccuracies Compared to Third-Party Meters:
Power Type: Confirm if your third-party meter reports real power or apparent power. The Vue 3 reports real power, which may undercount compared to apparent power measurements.
Amps vs. Watts: The Vue 3 aims for +/-2% accuracy compared to utility meter kWh (Watts). Limited inaccuracies may occur when viewing amperage.
Duplicate Sensor Test: As above, adding another CT to the same line can help determine if the issue is with the device/sensors or the system/appliance.
Feedback and Suggestions
Our goal is to provide comprehensive information to help you manage your energy usage effectively. If this article was not helpful or if you have suggestions for improvement, please reach out to our Customer Support team. We are committed to enhancing our guides based on your feedback.