Save up to 30% on energy costs by using Midea heat pumps' SG-ready contacts via the Reduxi Gateway, enabling dynamic control to align with fluctuating energy prices.

1. Required components for connecting the Reduxi controller to the Midea heat pump.

To establish the connection between the Reduxi controller and the Midea heat pump, two components are needed:

1. Reduxi Controller
2. Reduxi Gateway device with 3x (30:1A) current sensors (CTs)

The Reduxi Gateway device must be first added (connected) to the Reduxi controller to control/commission the heat pump operation modes. The connection can be established wirelessly (WLAN) or wirely via a UTP cable (LAN). You can find more about the connection at the Gateway to Controller connection. The Reduxi Gateway device also includes 3x(30:1A) current sensors (transformer) used to measure the electrical current (i.e. power) for each phase of the heat pump. Additionally, two relay outputs are used to generate signals for SG-ready contacts, affecting the heat pump operation modes. 

2. Connecting a Reduxi controller and Gateway device to the local network

A symbolic picture of the entire connection from the Reduxi controller to the heat pump is displayed below:

For further information on connecting a Reduxi Gateway device, please follow the link: How to configure Reduxi Gatway.

3. Connecting Reduxi GW device's relay to SG-ready contacts of a heat pump

To physically connect the relays of the Reduxi Gateway device to the SG-ready contacts on the heat pump, it is essential to determine the exact locations of the SG-ready contacts on the heat pump’s circuit board. The image below shows the locations of the SG-ready contacts on the Midea
heat pump's circuit board.  The second image displays connections from relays to SG-ready contacts.

SG-ready contacts on the HP circuit board CN35:

Connection from Reduxi GW device to SG-ready contacts on HP:

NO contact of the first relay of the Reduxi GW device --> 1st contact on CN35 connector; Black wire

COM contact of the first relay of Reduxi GW device --> 2nd contact on CN35 connector; Green wire

NC contact of the second relay of the Reduxi GW device --> 3rd contact on CN35 connector; Blue wire

COM contact of the second relay of Reduxi GW device --> 4th contact on CN35 connector; Brown wire

Connection:

Please note: The Reduxi Gateway device allows to use of relay outputs ass permanently closed " Normally Closed - NC " or opened " Normally Opened - NO ", whereas in the case of the heat Stiebel Eltron, NO contacts are used.

4. Reduxi Gateway device as a meter with current sensors

The current sensors (CTs) included in the Reduxi Gateway kit must be connected to three inputs, one for each phase, as illustrated in the image below. 

The current sensor covers the individual phase wire (L1, L2, L3) of the heat pump, picture below:

5. Adding heat pump as a new device in the Reduxi configurator

To add a new heat pump as a device or to edit an existing one, please follow these steps, detailed in individual points below.

5.1 Adding a device

Log in locally to the Reduxi configurator application on the controller and press the Add device button.

5.2 Select the device you would like to add

In the first step (basic settings), select the basic parameters of the device you want to add:

• Device type: HVAC,
• Type: Redxi Meter
• Name: Specify the name of the device.

5.3 Communication channel

The first part of the communication channel setup is designed for connecting between the Reduxi Gateway device and the Reduxi controller. Complete the fields as displayed in the image below (automatically populated).

The second part of the communication channel is intended for the current sensor settings of the Reduxi Gateway device, where we choose "Auto detect from gateway" for all current sensors. 

The third part of the communication channel is dedicated to the definition of signals from the relays of the Redux GW device.

The logic of SG-ready signals combination definition:

ON mode (Normal operation mode), the first relay (EVU contact) is opened (NO) and the second (SG-ready) is closed (NC):

OFF mode (OFF operation mode), the first relay (EVU contact) is opened (NO) and the second (SG-ready) is opened (NO):

ECO mode (ECO operation mode), the first relay (EVU contact) is closed (NC) and the second (SG-ready) is opened (NO):

BOOST mode (ECO operation mode), the first relay (EVU contact) is closed (NC) and the second (SG-ready) is opened (NC):

Tabel for operation modes:

 note NO stands for normally opened :

Complete configuration of the Relays signals in Reduxi configuration:

5.5 Communication test 

The communication test is carried out with the help of the "Test communication" button, located on the lower right side after all the parameters fields of the communication channel.

The communication test can return two answers:

1. Communication is working properly, picture below:

2. Communication is not working properly, the picture below:

5.6 Advanced Settings

The advanced setting is arbitrary and depends on the specific needs of the location where the Reduxi controller is installed. After finishing all the advanced settings, press the "Done" button on the lower right side.

5.7 Last measurements

After successfully establishing communication with the newly added device, its values ​can be checked under Devices/Midea HP in the Reduxi configurator as an additional test. 

For advanced heat pump control, integrate the device into the Reduxi system strategy. Under Devices/Midea HP in the Reduxi configurator, the control type must be set to AUTO so commands for strategy will affect the HP.

To achieve maximal flexibility and energy cost reduction with respect to dynamic price and dynamic tariffs please follow the instructions on how to define strategy at this link: Strategies for Reduxi controller.

After successfully adding the device and checking the values, the device can be inspected and controlled also via the Reduxi application.