Metering Error
Enphase Microinverter
Severity: MinorWhat Does This Error Mean?
Enphase metering error means the Envoy's current transformers (CT clamps) are not reading consumption or production data correctly. The solar panels are still producing and sending power to the grid — only the energy measurement is affected. Most metering errors are caused by a CT clamp installed backwards, on the wrong conductor, or with a broken cable.
Affected Models
- Enphase Envoy-S Metered
- Enphase IQ Envoy (metered version)
- Enphase IQ Gateway (metered version)
- Enphase IQ Combiner 4C
Common Causes
- CT clamp installed with the arrow pointing the wrong direction — reverses the reading to negative
- Production CT clamp installed on the wrong conductor — reading grid import instead of solar output
- CT clamp cable damaged, pinched in the meter box door, or connector loose at the Envoy
- CT clamp not fully closed around the conductor — a small gap prevents accurate measurement
- Both CT clamps installed on the same phase — missing one leg of a split-phase system
How to Fix It
-
Check Enlighten for the specific metering alert.
Log in to Enlighten Manager and check the Alerts tab. Alerts such as 'Production CT reversed', 'Negative net consumption', or 'Metering not communicating' each point to a specific cause. Screenshot the alert for your installer.
-
Check whether consumption shows as negative in Enlighten.
If your net consumption graph shows large negative values at times when you are clearly using power, one CT clamp is installed backwards. This is a common installation error — the arrow on the CT must point in the direction of current flow toward the loads.
-
Verify the CT clamp cable is undamaged and connected.
If you can safely access the Envoy (not the live meter box), check that the CT clamp cables are fully plugged into the Envoy's CT inputs. The connectors are small white plugs on the side of the Envoy. A loose connection causes metering to drop out intermittently.
-
Contact your installer to inspect the CT clamp installation.
CT clamps are installed inside the main switchboard on the live AC conductors. Correcting the orientation, position, or conductor selection requires a licensed electrician. Do not attempt this yourself — the conductors are always live.
When to Call a Professional
CT clamp inspection and adjustment requires working inside a live electrical meter box. This work must be performed by a licensed electrician or your Enphase installer.
Frequently Asked Questions
Does a metering error affect how much power my solar system produces?
No. The microinverters produce the same amount of power regardless of whether the Envoy is measuring it correctly. A metering error only affects the numbers shown in Enlighten.
Why does my Enphase system show more consumption than my utility meter?
If Enlighten shows higher consumption than your utility meter, the production CT clamp may be placed on the grid feed wire instead of the solar output wire, causing solar production to be counted as consumption. Your installer needs to reposition the CT.