How to check CTs

On the system, we can see the error message “Meter issue”.

The problem in this case will be related to the installation of the current transformers.

In single-phase systems, we will have one CT for the production and one for the consumption.

In three-phase systems, we will have three CTs for the production and three for the consumption. In order to have the data for all three phases, we MUST power up the gateway on the three phases.

If the CTs are installed, make sure that the production readings are showing the meter measurements. If they are activated, the small M in blue is displayed on your overview. You can change this view in the settings.

Please note: You have two possible displays:

  • Meter measurements. This value is read by the current transformers and requires their correct installation. This is the most accurate option.

  • Microinverter measurements. This corresponds to the production transmitted from the microinverters over PLC. It requires good PLC communication.

The setting you choose will also be shown on the customer’s Energy tab. If the meter measurements are not correct, the client won’t see the real production.

When we see the “meter issue” error message, we go the “graph” tab to see the values and where the error might be.

On Enphase Installer Platform, the consumption must always be positive!

This is the total consumption of the house, not the consumption (import) from the grid.

Hover over the graph to see the values displayed.

Remember: If it is a 3P system, make sure you activate the consumption view per phase by selecting the “Show phases” option.


The production CT should be placed on the line that comes down from the microinverters.

If you have multiple circuits, you can pass both phase wires (only if they are the same phase) through the same CT. Additional CTs can be installed and connected in parallel on the corresponding CT terminal if needed.

  • Must be positive and match the microinverter production curve by day. At night it must be 0W

  • Possible issues with production CTs are:

    • The production CT might be reading some consumption and not only the microinverter activity. Make sure it is 0W at night or when the system is turned off.

    • The production CT might not be connected on the correct terminal of the gateway. The first three on the gateway are dedicated for the production. Please check the sticker on the gateway to make sure they are being installed correctly.

    • White cable needs to be on top and blue on the bottom.

    • It should be on the phase wire only.

    • Arrow needs to be pointing inwards in the current flow direction. Pointing to the loads. Not to the microinverters.

    • They are not on the correct phase. The phases are determined by the gateway power feed.

      The production values will not be coherent, and production at night will be displayed.

    • If storage is installed, make sure that the activity is not being read by the production CT. The production CT must only read the production.

    • Is all the production read? If not, it will be reflected on the consumption graph. We can compare with the values transmitted by the microinverters:


First, check the values at night.

There are two possible configurations depending on where we have placed our consumption CT, with load with solar configuration being the most common one. Please note: The consumption values in this configuration are an interaction between the consumption CT AND production CT:

Consumption = consumption CT reading (import/export) + production CT.

Therefore, it is always recommended to first check the values at night to know if it is a consumption CT problem or if the incorrect values are only showing during the day. It might be related to the installation of the production CT. (For example, not all the production is being measured)

  • Consumption must always be positive. Even if there is energy being exported to the grid, there will be always consumption in the house.

Possible reasons for consumption not being measured correctly:

  • Polarity.

    • Arrow in the right direction. It should be pointing towards the loads.

    • White cable needs to be on top and blue on the bottom.

  • On the phase wire AND on the correct phase. In 3P systems, the phases are determined by the gateway power feed (link to document on how to check phase correspondence and best practices)

  • In three-phase systems, at night, at least one phase is going from positive to negative values, it is most likely due to not being connected on the correct phase.

Not measuring anything? Are they connected on the correct terminal? Have they been made longer?

  • If storage has been installed, make sure that the activity is being read by the consumption CT. Otherwise, the error “Meter issue – Storage measurements” will be shown

  • Negative values ONLY during the day? The issue might come from the production measurement. Is all the production being measured? Is a third-party inverter present?

  • Is the configuration correct? Load with solar production vs load only.

Important: If the system is configured in NET (load with solar production) but the physical location of the CTs is in TOTAL (load only), the production will follow the consumption and will always be lower.

On the other hand, if your configuration is in TOTAL and the CT location is in NET, your consumption will be at zero (in this configuration ENL Manager does not show the negative consumption, you can see it only by logging in to the ITK app).

Neither configuration is good with respect to the CT location.

We can check the current configuration and phase count on the “Devices” tab

Configuring the meters to three phase and powering the gateway single phase will stop the production of the microinverters. In this case, the gateway will display an error message and a red icon.

The configuration is set to NET, with the CT placement in TOTAL

Check that the system is not set up with the “Zero export” profile

The configuration is set to TOTAL, with the CT physical placement in NET


To change the configuration, you must first deactivate the meter, wait for the command to be taken into account (this can take up to 15 minutes) and activate the meters again with the correct configuration.

When you change the configuration, a peak in consumption may appear. It is necessary to zoom in on the graph by dragging the cursor after the peak to see the new values.