Energy trader commands (RPC license)

Last modified: 05 Sep 2025

Note

The content on this page refers only to the blue'Log XC combined with the Hybrid EMS licence.

About energy trader commands and remote power control

In addition to the grid operator, an energy trader (also known as a third party, solar power trader, direct marketer) can send power control setpoints. The blue'Log XC is compatible with several energy traders, and you can activate a separate, additional interface for Remote power control (RPC).  The controller interprets the energy trader's control signals and transfers them to the plant. Optionally, a ramp rate limiter can be applied to the energy trader setpoint. If the grid operator and energy trader setpoints temporarily overlap, the lower setpoint is given priority.

Note

For third-party power control, we recommend using the blue'Log instead of an external PLC. This enables the blue'Log to record data from the grid operator and the third party separately. This is useful, for example, when calculating yield losses due to power curtailments.

Feed-in meter selection

In some scenarios, for example, mixed installation plants, multiple meters are installed at different locations within the plant.

• Typically, energy traders prefer to receive the active power measurements from the meter installed at the grid connection point (feed-in meter).

• Under Meter for feed-in power, select which meter should provide the active power value transmitted to the energy trader. This value corresponds to register 5406.

• You can also use the RPC interface without selecting a meter. In this case, register 5406 will be empty.

Read and write registers

The read and write registers are listed in the Remote Power Control datasheet: Downloads - meteocontrol GmbH.

Note
The datasheet contains two separate sections:

• Registers for the blue’Log XC without the Hybrid EMS licence.

• Registers for the blue’Log XC with the Hybrid EMS licence.

Even if the Hybrid EMS license is installed, you can also use the registers for the blue’Log without the Hybrid EMS license. See the section on Compatibility mode.

Define setpoints

To define setpoints, the energy trader must always write two registers:

• A register for activation of the signal (0 = off / 1 = on).

• A register for the setpoint value (e.g, 40%).

If the activation register is not activated, the setpoint will be ignored.

Activate remote power control

Prerequisites

• blue’Log XC

• Hybrid EMS license is installed

• Remote power control license is installed

• OpenVPN license is installed and OpenVPN is activated

Steps

1. Navigate to Power control > Active power > Energy trader commands.

2. Select a location for the setpoint and meter.

3. If required, activate the Ramp rate limiter and set the ramp rates.

4. Check that Remote Power Control is active under Cockpit > System settings.

5. Confirm that the VPN connection is enabled and running under System > VPN connection > Connection status.

The third party can now carry out active power control.

Troubleshooting: Energy trader can not enable active power control

Problem

An energy trader can not enable power control.

Solution

Confirm that:

• The VPN connection to the energy trader is enabled and running.

• There is no further access from an energy trader, e.g. via a VPN router or a device for energy trading (German e.g.: ”Steuerbox für Direktvermarktung”).

• All other RPC settings are configured correctly.

• If you require further assistance, contact Support.

Compatibility mode

Compatibility mode activates the RPC legacy registers used for the blue’Log XC without the Hybrid EMS license. It ensures compatibility with existing systems and energy traders. The Hybrid EMS registers are not available in this mode.

Prerequisites

• Hybrid EMS license

• PV-only system. This mode is not available if you have configured a battery under Active power > Plant data.

Steps

1. Go to Power Control > Energy trader commands.

2. Activate the Compatibility mode toggle.

Compatibility mode is activated.