---
title: Configure the L1, L2 and L3 phases of a three-phase Chart’nX meter
description: Enter a KNX address or a Modbus configuration for each phase L1, L2, L3 and choose a measured or calculated total for a three-phase Chart’nX meter.
canonical: https://wiki.can-nx.com/en/guides/chart-meter-phases/
language: en
product: Chart’nX
audience:
  - administrateur
  - installateur
context: "Chart’nX: energy generator in a three-phase installation, main meter cards"
---

# Configure the L1, L2 and L3 phases of a three-phase Chart’nX meter

Context: Chart’nX: energy generator in a three-phase installation, main meter cards

In a three-phase installation, the Chart’nX energy generator can read a meter phase by phase: a KNX group address or a Modbus configuration for **L1**, **L2** and **L3**, with a total measured separately or calculated from the phases. This setting does not change the physical wiring.

For installers or administrators in charge of the configuration.

## Before you start

- **Three-phase** is chosen in **Electrical system**, in the [general information of the dashboard](https://wiki.can-nx.com/en/guides/chart-general/).
- You know the measurement and the correct address of each phase.

## Switch the card to per-phase measurement

1. In **Main meters**, enable the relevant card and choose the protocol according to the table below.
2. In **Measurement**, select **Per phase**. The **L1**, **L2** and **L3** rows appear.

| Card | Phases | **Total** choice |
| --- | --- | --- |
| **General meters - Apparent power** | **KNX** or **Modbus** | No: the total measurement is still required in addition to the phases |
| **General meters - Total energy consumed** | **KNX** or **Modbus** | Yes |
| **PV meter** and **Grid meter** | **KNX** or **Modbus** | Yes |
| **Battery meter** | **KNX** only | Yes; the dedicated total keeps the **Group address** label |

Ordinary energy submeters and the water generator do not offer this per-phase configuration block.

## Fill in the address of each phase

1. In KNX, fill in the address of each phase. The format has three levels: first number from 0 to 31, second from 0 to 7, third from 0 to 255. Fictitious example: **1/2/3**.
2. In Modbus, choose for each phase the matching configuration from the catalog. The U identifiers and R registers help to recognize the configurations.
3. To add an old KNX address to a phase, click its small clock button with **+**, tooltip **Add historical address**, then fill in the new **Historical** row. An added historical row must be filled in; its cross removes it.

## Choose the total and save

1. If **Total** is offered, choose **Dedicated address** for a total measurement provided separately by the meter, or **Sum L1+L2+L3** to calculate the total from the phases. The sum hides the total measurement field.
2. With **Dedicated address**, also fill in **Measured total address**. The **General meters - Apparent power** card keeps this total measurement in addition to the phases and does not offer the sum.
3. Check the units and the **Index** or **Not indexed** mode according to [the meter fields](https://wiki.can-nx.com/en/guides/chart-meters/). In **Per phase** mode, the meter unit applies to the L1, L2, L3 addresses and to the total.
4. [Save the dashboard](https://wiki.can-nx.com/en/guides/chart-save/).

## Return to the total measurement

**Total** returns to the overall measurement. **Per-phase configuration preserved** indicates that the phase addresses remain stored while their view is inactive: reread them when you reactivate **Per phase**. After a protocol change, check all the fields, as the same values are not necessarily kept.

## Check the result

After saving, open the [per-phase panels](https://wiki.can-nx.com/en/guides/chart-phases/) and compare each phase with the measurement expected on the installation. If a phase stays empty or inconsistent, reread its address and the meter unit.

## Troubleshooting

- A warning symbol next to a KNX phase, with the tooltip **Address already used by another phase or as historical**, flags an address conflict to examine. It does not prevent saving: check the match with the installation before changing an address. Do not replace an address with a fictitious value to make the warning disappear.
- The **Measurement** choice is missing: check the installation type, the card and the protocol.

For other symptoms, follow the [meter troubleshooting](https://wiki.can-nx.com/en/guides/chart-meter-help/). If the flow is still different, contact support@can-nx.com with the card, the protocol and the installation type.