# Load Management

> Load management groups charging points into circuits with a maximum current or power so that several wallboxes never overload your electrical installation.

> **Experimental**
>
> The Load Management feature is still experimental. It may not perform as expected in combination with some other features.

The load management/load balancing feature can be used to limit the power used by chargers to prevent overloading the circuits and tripping breakers. By limiting the power, it could also be useful if you want to avoid accidental high peak usage. To accomplish this, a charging point can be assigned to a `circuit`. A `circuit` can have a maximum current value (`maxCurrent`) and/or a maximum power value (`maxPower`). The system works hierarchically, i.e., an electrical circuit can be part of a higher-level electrical circuit.

> **Configuration via UI**
>
> This page describes the configuration via the `evcc.yaml` file. Configuration is also possible via the UI.
>
> Circuits can be defined under **Configuration → Load Management**. The input uses YAML format and corresponds to the content below `circuits:` in the examples that follow. We are working on replacing this with a form-based approach.
>
> Each charging point can then (restart required) be assigned to a circuit under **Configuration → Charging points & Heaters → \[name]**.

## Configuration

The section `circuits` defines the circuits. Each charging point can then be assigned to an electrical circuit.

### Example: Main Circuit

```yaml
circuits:
  - name: main # if there is only one circuit defined the name needs to be 'main'
    title: "main circuit" # name for the UI (not implemented in UI yet)
    maxCurrent: 63 # 63A (optional)
    maxPower: 30000 # 30kW (optional)
    meter: grid # optional


loadpoints:
  - title: Garage
    circuit: main
```

This configuration only configures a main circuit. The circuit has a maximum current of 63A. If there are other consumers like an oven/heat pump (this requires a meter) using a total of 50A, the charger will only be allowed to use 13A. The circuit has a limit of 30kW. Since the grid meter is assigned to this circuit, the power of the charging points will be throttled so that the limits ​​are not exceeded at the grid connection. Without the grid meter assigned, the limits apply directly to the sum of all charging points.

### Example: Nested Circuits

```yaml
circuits:
  - name: main
    title: "main circuit"
    maxCurrent: 48
  - name: garage
    title: Garage
    maxCurrent: 32
    parent: main
  - name: carport
    title: Carport
    maxCurrent: 32
    parent: main


loadpoints:
  - title: Garage A
    circuit: garage
  - title: Garage B
    circuit: garage
  - title: Garage C
    circuit: garage
  - title: Carport A
    circuit: carport
  - title: Carport B
    circuit: carport
  - title: Heat Pump
    circuit: main
```

Here we have two circuits, `garage` and `carport`, both of which are children/downstream of the main circuit (`parent: main`). The `main` circuit has a maximum current of 48A. The circuits `garage` and `carport` each have a maximum current of 32A. The charging points Garage A, Garage B, and Garage C are assigned to the `garage` circuit (`circuit: garage`). The charging points Carport A and Carport B are assigned to the `carport` circuit (`circuit: carport`). The circuits `garage`, `carport`, and the heat pump are connected directly to the root circuit (`main`). The regulation ensures that the limits of the respective circuits are not exceeded at any time.

**Important:** There must always be exactly one root circuit (a circuit without `parent` property).

> **External Limit (§ 14a, § 9)**
>
> When an [external limit](/en/external-limit) is active, it caps the power of the root circuit. This is indicated by a “Consumption limited” hint on the Load Management card.

## Measuring

By default, the control system calculates the current power and current from the sum of the respective charging points. By configuring a `meter` on a `circuit`, the real load can also be taken into account. This is particularly useful if other consumers are also connected to the fuse.

```yaml
site:
  meters:
    ext:
      - carport_meter


meters:
  - name: carport_meter
    type: template
    template: shelly-3em


circuits:
  - name: carport
    meter: carport_meter
    maxCurrent: 32
```

Note: If a meter is used that is not yet used for another purpose (e.g. `grid`), it must be linked as an external meter under `site.meters.ext`.

## Limits

Both a maximum current per phase (`maxCurrent`) and a maximum power (`maxPower`) can be configured on each circuit. These values, if configured, are monitored independently of each other.

### External limits

If necessary, external limits can also be defined using `GetMaxCurrent` and `GetMaxPower`. In the event of an error, the predefined limits apply.

Example:

```yaml
circuits:
  - name: main
    title: "main circuit"
    maxCurrent: 48
    GetMaxCurrent:
      source: mqtt
      topic: ext/maxcurrent
    maxPower: 33000
    GetMaxPower:
      source: mqtt
      topic: ext/maxpower
```

> **Note**
>
> An external limit can be used to implement control requests from the grid operator. For more information, see [External Limit](/en/external-limit).

## Phase Switching

For chargers with automatic phase switching (1P/3P), load management can use the switching capability to charge within the configured limits. When available power is insufficient for 3-phase charging, evcc automatically switches to 1-phase charging.

This applies to fast charging and plan-based charging as well. For example, if load management limits available power to 3.5 kW, evcc switches to 1-phase charging (from 1.4 kW) instead of pausing the charge.

**Requirement:** The charger must support phase switching.

## Charger Configuration

Some chargers come with their own load management features. It is strongly recommended to disable these or use chargers without built-in intelligence. evcc expects devices to follow its commands directly. Other configurations may cause unexpected behaviour and must be tested thoroughly on your own.

## Restrictions

> **Note**
>
> A separate license will be required later for commercial use of load management. Private use with smaller installations will remain free of charge.

* Current values and limits of individual circuits are displayed on the configuration page in the UI. Visualization at the charging point is planned.
* `priority` settings at the charging point are not yet taken into account.
* New sessions receive only the remaining circuit headroom. Rebalancing across active sessions is not yet supported.
* Home battery [grid charging](/en/features/battery#gridcharge) is not considered. When the home battery actively charges from the grid, this consumption is not included in load management calculations. However, during active [§ 14a power reduction](/en/external-limit) signals, grid charging is automatically paused.