How to connect CHINT POWER CPS ES-125kW-261kWh-EU energy storage system with Reduxi controller
Integrate the CHINT C&I energy storage system with the Reduxi controller via Modbus TCP/IP for maximum flexibility and lower energy costs.
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Product photo (manufacturer image) of a free-standing white outdoor energy storage cabinet with the 'CHINT POWER' logo (green leaf symbol) on the upper front of the door. A red emergency button sits in a recess at the top right of the front and another round yellow-and-red emergency stop button in the middle of the door; a small black round button is below the logo. The door has a black handle on the left edge. Perforated ventilation grilles are in the lower part of the door and above the plinth. Shown on a white background.
1 Technical documentation
The key facts below come from the manufacturer's datasheet for the CPS ES-125kW/261kWh-EU.
Manufacturer documents:
- Datasheet – CPS ES-125kW/261kWh-EU (PDF, EN)
- User manual – US edition, Rev. 1.6 (PDF, EN)
- User manual, EU model – CPS ES-125kW/261kWh-EU, v2.1, April 2026 (PDF, EN)
- CHINT POWER product page – CPS ES-125kW/261kWh-EU
2 Required equipment
- Reduxi Controller (installed and online)
- CHINT CPS ES-125kW-261kWh-EU Energy Storage System, commissioned
- Ethernet cable (Cat5 or Cat6) for the LAN1 port of the LEMS module
- Local network shared by the ESS and the Reduxi controller, or a direct cable connection to the Reduxi device
- IP address of the ESS (you can find it with the network scan in the Reduxi Configurator)
- Laptop or tablet with internet access to configure the device in Reduxi
3 System overview & wiring
The CHINT Energy Storage System (ESS) supports the Modbus TCP protocol for communication with the Reduxi controller. Connect it with an Ethernet cable (Cat5 or Cat6) to the same local network as the Reduxi controller, or directly to the Reduxi device. The connection is made through the LAN1 network port on the LEMS module of the ESS.
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Diagram of the network connection. Components: Reduxi controller (grey box with reduxi logo, label 'Controller'); Router (white Wi-Fi router, label 'Router'); WWW globe icon (internet); CHINT ESS cabinet (white cabinet with CHINT POWER logo, red switch and label 'CHINT ESS CPS'). Connections: Controller to Router: solid light blue line labelled 'Ethernet'; Router to CHINT ESS: solid light blue line labelled 'Ethernet'; Router to Internet (WWW): dashed light blue line.
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Manufacturer drawing, 'Figure 3-10 LEMS Location'. Left: line drawing of an open energy storage cabinet with battery modules stacked on the left and a door on the right; the LEMS module on the door is highlighted by a light blue box and a leader line labelled 'LEMS'. Right: a light-blue framed enlarged view of the LEMS module with a label '4n', a LAN port at the top, and two ports labelled 'COM1' and 'COM2'. A light-blue line runs from the top port to a teal Ethernet cable plug pointing downward, with the label 'Ethernet'.
4 Device configuration on the ESS
Two settings on the ESS prepare it for Reduxi: the Modbus TCP connection and the remote dispatch mode.
4.1 Modbus TCP
The ESS supports Modbus TCP communication for third-party EMS such as Reduxi. Communication runs through the LAN1 port of the LEMS module. In most installations, no dedicated “enable Modbus” action is required. After commissioning, make sure that:
- the LEMS has a valid IP address on the local network,
- Reduxi can reach the device over the network, and
- TCP port
502is open on the ESS.
If communication does not work, check the ESMU network settings in the local interface and consult the CHINT documentation or support.
4.2 EMS settings (System remote dispatch)
For Reduxi to control the CHINT ESS, adjust the settings in the web interface of the ESS.
The BMS is located on the inside of the door. If a password is requested when you activate the touch screen, enter the following default data:
Username: admin · Password: 12345678
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Manufacturer drawing, 'Figure 3-8 BMS Location' [as printed in the image]. Line drawing of an open energy storage cabinet with battery modules stacked on the left and a door on the right opened. A light blue square highlights a display panel on the inside of the door.
Afterwards you are taken to the main page of the system.
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Screenshot of the CHINT POWER ESS web interface. Top menu: Home, Setting (highlighted by a light blue box), Monitor, History, Operation, Help; top right: Auto button, user admin, language English. Left menu: Basic parameters (selected), On-grid, Off-grid, Equipment parameters, User management. Tabs: Strategy (selected), Economic, Others. Sub-tabs: Operation (selected), Backup, Fault handling, External ac solar. Fields: Dispatch mode: Self-consumption; Off-grid to On-grid: Manual; On-grid to Off-grid: Manual; Grid first policy: On-grid; Switch type: Non-seamless. Page selector at the bottom shows page 1.
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Screenshot of the CHINT POWER ESS web interface. Top menu: Home, Setting (selected), Monitor, History, Operation, Help; top right: Auto button, user admin, language. Left menu: Basic parameters (selected), On-grid, Off-grid, Equipment parameters, User management. Tabs: Strategy (selected), Economic, Others. Sub-tabs: Operation (selected), Backup, Fault handling, External ac solar. Fields: Dispatch mode: Self-consumption (text cut off as 'Self-consumptio') with the drop-down arrow highlighted by a light blue box; Off-grid to On-grid: Manual; On-grid to Off-grid: Manual; Grid first policy: On-grid; Switch type: Non-seamless. Page selector at the bottom shows page 1.
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Screenshot of the CHINT ESS web interface dialog 'Modify parameter' (close X at top right). Field: Dispatch mode (required) with the drop-down closed value 'Self-consu.' (cut off). The open list shows: No control; System remote dispatch (highlighted by a light blue box); Device remote dispatch; Self-consumption (in green, current value); TOU; Remote plan dispatch; Peak shaving; one more entry cut off at the bottom. A green button is partly hidden behind the list; the background page is greyed out.
5 Log in to the Reduxi web interface
The device is added in the Configurator, the web interface of the Reduxi Controller. You do not add it in the Reduxi app itself or in the Reduxi Cloud. You can open it in two ways:
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Screenshot of three Reduxi mobile app screens side by side, with cyan boxes and number badges 2 to 4. Left screen (dashboard, dark theme): menu icon at top left marked with a box and badge 2; 'reduxi' logo; tabs 'Real time data' (active) and 'Statistics'; price 5.79 € and temperature 3.2 °C; energy flow diagram with a house in the centre (-1.25 kW) and icons with values 69.0 W, 1.3 kW, 1.1 kW (red ring), -165.0 W with 97 % (red ring) and 0.0 W values at the bottom; tabs 'Power' and 'Energy'; bottom navigation: Dashboard, Diagnostics, Device control, Settings. Middle screen (side menu): 'reduxi' logo, 'Number of locations: 1233', heading 'Reduxi device management', entries '+ Add Reduxi location' and 'Reduxi devices' (marked with a box and badge 3), then 'My profile' and 'About app'. Right screen (device page): Back; picture of a black Reduxi controller with two Ethernet ports; status 'Connected'; card 'Update available': 'New update is available for your Reduxi device.' with button 'Download and install update'; card 'Connect to configurator': 'Tunnel connection enables remote access to your Reduxi configurator, without need to be connected to the same local network.' with button 'Activate tunnel connection' (marked with a box and badge 4); card 'Unit details' with field 'Unit ID'.
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Screenshot made of two parts side by side. Left part: Reduxi mobile app screen on a dark background. Top: Back button; picture of a black Reduxi controller with two Ethernet ports and a terminal block; status 'Connected' with a Wi-Fi icon. Card 'Update available': 'New update is available for your Reduxi device.' with button 'Download and install update'. Card 'Connect to configurator' with a key icon: 'Tunnel connection enables remote access to your Reduxi configurator, without need to be connected to the same local network.' and button 'Open configurator', marked with a cyan box and number badge 5. Below: card 'Unit details' with a field 'Unit ID' (value not visible). Right part: Reduxi Configurator opened in a browser, marked with a cyan frame and number badge 6. Header: back arrow, 'Tunnel connection', reload icon. Left sidebar with icons (lightning, chip, lightning bolt, bar chart, gear). Page 'Home' with a green link icon. Green notice: 'New patch available. Click here to apply.' with a close X. Time 09:12:56. Energy flow diagram with a house in the centre (1.700 kW) and icons for grid (0.000 kW), solar (1.700 kW), battery (green, 0.000 kW and 0.800 kW), a device at left (0.900 kW), electric vehicle and a charger or device at bottom. Label 'Energy manager' at the bottom.
reduxi.app), open the location, go to Manage location → OEM devices and click Activate tunnel connection. Confirm with OK, wait about 30 seconds and click Go to controller. The Configurator opens in a new tab without a password.http://reduxi.local. You find the IP address in the device list of your router or in the Reduxi app under Reduxi devices.admin · Password: admin (factory default). If the password was changed during installation, use that one. It is not your Reduxi account password.Text description of this image
Screenshot of the Reduxi Configurator login page in a Chrome browser window. The address bar shows 'Not secure' and 'reduxi.local'; the address bar is marked with a cyan box and an enlarged copy of it (cyan box, text 'Not secure reduxi.local') is shown at the left, connected by a cyan line. Page background: light grey line drawing of a house with solar panels (green), a wall box, an inverter, a car and a charger. Top left: 'reduxi configurator' logo. Login box in the centre with title 'Login', a language selector (English flag, 'English'), a username field and a password field, and a dark 'Login' button.
admin login is not your Reduxi account. reduxi.local only works in the same network as the controller.6 Add the CHINT ESS to Reduxi
Once the ESS is connected and configured (see Point 4) and the Configurator is open (see Point 5), register it as a new device (CHINT CPS ES-125kW-261kWh-EU).
6.1 Basic settings
Hybrid Inverter. Select Type: CHINT CPS ES-125kW-261kWh-EU. Name the device as you wish, for example Chint Power ESS.Text description of this image
Screenshot of the Reduxi Configurator sidebar. Header: reduxi Configurator logo. Section Devices (with a minus icon) lists: Iskraemeco AM550 (electricity pylon icon) and two entries with sun icons and no visible names. At the bottom is an Add device button with a plus sign, marked with a cyan rectangle.
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Screenshot of the Reduxi Configurator wizard step 1 'Basic settings' (step 2 'Communication channel' greyed). Form: Device type *: Hybrid inverter; Type *: CHINT CPS ES-125kW-261kWh-EU; Name *: Chint Power ESS. Buttons: Back, Next.
6.2 Communication settings
In the next step you configure the communication channel, which is essential for proper Modbus TCP/IP communication. It establishes the link between the Reduxi controller and the CHINT ESS.
| Parameter | Value |
|---|---|
| Connection | TCP/IP |
| IP | IP address of the CHINT ESS (you can scan the network to find the desired IP address) |
| Port | 502 |
| Modbus unit ID | The same ID as set on the inverter (default: 1) |
| Control mode | Choose which EMS modes are used to control the EMS |
| Are electricity meter and PV connected | Set to yes if the electricity meter and PV are connected directly to the ESS device |
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Screenshot of the Reduxi Configurator wizard step 2 'Communication channel' (step 1 'Basic settings' done), titled 'Communication channel and device configuration'. Fields: Connection *: TCP/IP; IP *: empty, with button 'Scan for IP'; Port *: 502; Modbus unit ID *: 1; Control mode *: EMS by inverter; Is electricity meter installed?: toggle Yes; Is PV installed?: toggle Yes. Buttons: Back, Test communication, Done.
6.3 Test communication
Below the fields of the communication channel, click Test communication. It reads the device once and saves nothing, and it verifies that the Modbus TCP/IP connection between the devices works. If the test is fine, click Done: only Done creates the device.
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Screenshot of the bottom button bar of a Reduxi Configurator page. Left: button 'Back'. Right: button 'Test communication' (marked with a cyan box) and dark button 'Done'.
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Screenshot of the Reduxi Configurator page 'Communication channel and device configuration'. Connection *: TCP/IP (dropdown). IP *: 192.168.50.243, with button 'Scan for IP'. Port *: 502, with button 'Test port'. Modbus unit ID *: 1. Buttons at the bottom: Back (left), Test communication and Done (right). The Done button is marked with a cyan box.
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Screenshot of the Reduxi Configurator dialog 'Test communication' (close X at top right). Text in green: 'Successful readout from device'. Values: Battery active power: 0.0 W; Battery current: 0.0 A; Battery export active energy: 0 Wh; Battery import active energy: 38000000 Wh; Battery max. active power: 750000.0 W; Battery state name: STANDBY null; Battery state of charge: 10.0 %; Battery temperature: 28.0 °C; Battery voltage: 830.9333 V; Error: false null; Inverter active power: 0.0 W; Inverter max. power: 750000.0 W; Inverter min. power: -750000.0 W; Operating mode: ON_GRID null; State name: STANDBY null; Additional parameter - BATTERY_SOH: 100.0. Button: Close.
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Screenshot of a dialog titled Test communication with a close x at the top right. Message in red text: Unable to communicate with device. Dark button at the bottom right: Close.
If the test fails, check the network cabling, the IP settings and the settings on the Reduxi controller, then try again.
7 Check the readings
7.1 Check the readings
Check the measured values of the device and whether it communicates correctly under Devices → Chint Power ESS → Last measurements.
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Screenshot of the Reduxi Configurator device page, tab 'Last measurements' selected (other tabs: Analyze, Archive, Details). Card 'Control type': buttons Auto (selected) and Manual. Card 'Battery' rows (label: value): Active power: 0.0; Current: 0.00 A; Voltage: 830.93 V; Battery state: STANDBY; State of charge: 10.00 %; next row: 10.00 %; Capacity: 156.6; Max capacity: 1,566.0; next row: 100.00 %; Import active energy: 38,000.00; Temperature: 28.00; Export active energy: 0.0; next row: 0.0; Max. active power: 750.0; Active power setpoint: 0.0. Card 'Inverter' rows: Active power: 0.0; Max. active power: 750.0; Min. active power: -750.0; State: STANDBY; Error: OFF; Operating mode: ON_GRID. Card 'Other': Communication error: OFF; Control type: AUTO; Mode name setpoint: SETPOINT. Each value has a date and time stamp.
7.2 Enable control by Reduxi
For advanced control, integrate the device into the optimization modes of the Reduxi system. Under Devices → Chint Power ESS in the Reduxi configurator, set the control type to AUTO so that the commands of the strategy affect the battery.
To achieve maximum flexibility and lower energy costs with dynamic prices and dynamic tariffs, define your strategy as described in Strategies for Reduxi controller.
After you have added the device successfully, you can monitor and control it via the Reduxi application.
✓ Summary
Preparation (Points 1–3): Read the manufacturer documents, prepare the Ethernet cable and a laptop or tablet, and connect the LAN1 port of the LEMS module to the local network of the Reduxi controller.
CHINT ESS (Point 4): Make sure the LEMS has a valid IP address and TCP port 502 is open, then activate System remote dispatch in the ESS settings.
Add to Reduxi (Points 5–6): Open the Configurator, add the device with type CHINT CPS ES-125kW-261kWh-EU, enter IP address, port 502 and Modbus unit ID (default 1), and run Test communication.
Go live (Point 7): Check the readings under Last measurements and set the control type to AUTO.
→ Common issues
| Issue | Solution |
|---|---|
| Test communication shows “Unable to communicate with device”, device offline | Check the network cabling, the IP settings and the settings on the Reduxi controller. Check that the ESS is reachable, that IP address, port 502 and Modbus unit ID are correct and that Modbus TCP is available on the ESS (see Point 4). |
| No communication although the cable is connected | Check that the LEMS has a valid IP address on the local network, that Reduxi can reach the device and that TCP port 502 is open on the ESS. Check the ESMU network settings in the local interface and consult the CHINT documentation or support. |
| The touch screen asks for a password | Enter the default data: Username admin · Password 12345678. |
| Reduxi commands have no effect on the battery | Check that System remote dispatch is activated on the ESS (see Point 4) and that the control type in Reduxi is set to AUTO (see Point 7). |
| Open configurator does not open or stays empty | The tunnel is not active yet. Wait about 30 seconds and check that the controller is online. |
Login with admin is rejected |
The password was probably changed during installation: ask the installer. The Reduxi account password does not work there. |
reduxi.local does not load |
You are not in the same network as the controller. Use the IP address or the tunnel. |