How to connect M-Tec hybrid inverter with Reduxi controller
Save up to 70% on costs: connect the M-Tec Energy Butler GEN 3 hybrid inverter to the Reduxi Controller via Modbus TCP/IP.
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Photo of the M-Tec Energy Butler GEN 3 on a white background: a tall white stack of modules (inverter on top, battery modules below, on a base) with a dark display strip on the front of the top unit. On the right, the M-TEC logo in black with an orange M, and the tagline ENERGY FOR FUTURE.
1 Prepare the M-Tec Energy Butler GEN 3
1.1 Required equipment
- M-Tec Energy Butler GEN 3 with the LAN module
- Reduxi Controller
- Ethernet cables
- Router or switch
- Laptop or tablet with internet access to configure the device in Reduxi
1.2 Install the latest firmware
With the latest firmware, the Modbus connection is enabled automatically. To update the firmware, contact M-Tec customer service: https://www.mtec-systems.com/serviceanfragen/
1.3 Connect the LAN module
The LAN module is included in the delivery of the Energy Butler. Connect it to COM 1 on the inverter.
The diagram shows the module:
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Line drawing in black and white with three parts. Left: the LAN module (a tall rounded dongle with a ribbed connector ring and plug at the top) with two callouts: LED Display (pointing to a small rectangular window) and ON/OFF Button (pointing to a round button below it). Top right: a drawing of the inverter housing seen from an angle, and next to it a circular close-up of the module plugged into a socket on the underside of the inverter. Below: a front view of the inverter connection area with numbered ports 3, 4, 5, 6, 7, 8, 9; port 6 is highlighted with a cyan box. A small table below reads: 6 | COM1-Anschluss [COM1 connection]; WiFi- / LAN-Modul-Anschluss [WiFi / LAN module connection].
2 Physical connection
The picture shows the entire connection from the Reduxi Controller to the inverter.
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Diagram of the physical connection of a Reduxi controller to an M-Tec Energy Butler. Top left: the Reduxi controller (dark grey box with reduxi logo), labelled Controller. A solid cyan line labelled Ethernet runs from the controller Ethernet port down to a white router in the centre, labelled Router. Bottom left: a globe icon with the text WWW, joined to the router by a dashed cyan line (internet). Right: a tall stack of white units: the inverter at the top and a battery module directly below it, followed by several more battery modules on a base. Two cyan lines run from the router to the stack: one labelled Inverter Ethernet to the inverter and one labelled Battery Ethernet to the battery module below the inverter.
3 Set the IP address on the M-Tec Energy Butler GEN 3
3.1 Display and menu button
You set the IP address locally on the display of the inverter.
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Picture of a white wall-mounted inverter housing at the top left, with a cyan line leading from its front panel to an enlarged view of the panel in a cyan frame. The enlarged panel is black and shows, from left to right: a battery symbol with bars and a lightning bolt, labelled battery charge status; a power symbol, labelled on off display; a network symbol, labelled network display; a warning triangle, labelled alarm display; a grey rectangular screen, labelled display; and a small button below the screen, labelled button / push button. Red lines connect each label to its element.
3.2 Menu navigation
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Screenshot of a small inverter display menu entry in a light blue box with a teal border. Text on two lines: General, Settings.
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Screenshot of a small inverter display menu in a white box with a teal border. Text on three lines: <General>, DHCP Set, ON.
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Screenshot of a small inverter display menu in a white box with a teal border. Text on three lines: <General>, DHCP Set, OFF.
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Flow diagram of inverter display screens, six boxes with blue borders in two columns. Left column from top to bottom: <General> IP Addr 192.168.0.10; <General> Gateway Addr 192.168.0.1; <General> Subnet Mask 255.255.0.0. Blue arrows labelled 1s point down between the left boxes. Right column, same order and same texts: <General> IP Addr 192.168.0.10; <General> Gateway Addr 192.168.0.1; <General> Subnet Mask 255.255.0.0. A dotted blue arrow labelled 3s points from each left box to the right box in the same row.
4 Log in to the Reduxi web interface
You can open the Reduxi web interface 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.
http://reduxi.local. You can find the controller's IP address in your router's device list or in the Reduxi app under Reduxi devices.admin · Password: admin (factory default)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.
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Screenshot of the Reduxi Configurator web interface after login, light theme. Top left: 'reduxi configurator' logo. Header bar: 'Home' at left, green 'Connected' status at top right. Left sidebar: expanded section 'Devices' with a list of entries, then collapsed sections 'Manager' and 'Configuration' and 'Settings'. Main area: energy flow diagram. House in the centre with ring, value 24.20 kW. Grid icon at top left, 24.20 kW (red dot on its line). Solar icon at top right, value '-'. Left icon (battery or device), 6.700 kW (green dot on its line). Right icons (battery storage and a device), values '-'. EV charger icon at bottom left, 31.00 kW. A further device icon at bottom right. Label 'Energy manager' below the house.
5 Add the M-Tec Energy Butler GEN 3 to Reduxi
After you connect the Reduxi Controller and the M-Tec Energy Butler, register it as a new device.
5.1 Basic settings
Log in to the local Reduxi Configurator (see Point 4) and click + Add device.
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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.
In the first step, select the basic settings:
- Device type:
Hybrid Inverter - Type:
M-Tec Energy Butler GEN 3 - Name: a name of your choice, for example M-Tec Energy Butler GEN 3
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Screenshot of the Reduxi Configurator, step 1 of 2 Basic settings. Step indicator: 1 Basic settings (active), 2 Communication channel (grey). Form Basic settings: Device type (required): Hybrid inverter; Type (required): empty dropdown; Name (required): M-Tec Energy Butler GEN 3. Buttons: Back (left), Next (right, dark).
Click Next.
5.2 Communication settings
The second step sets up the communication channel for Modbus TCP/IP between the Reduxi Controller and the inverter:
| Parameter | Value |
|---|---|
| Connection | TCP/IP |
| IP | The IP address of the M-Tec Energy Butler GEN 3 (see Point 3) |
| Port | 502 |
| Modbus unit ID |
255: the default value of M-Tec |
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Screenshot of the Reduxi Configurator, step 2 of 2 Communication channel. Step indicator: 1 Basic settings, 2 Communication channel (active). Form titled Communication channel and device configuration: Connection (required): TCP/IP; IP (required): empty, marked with a cyan rectangle; Port (required): 502; Modbus unit ID (required): 1. Buttons: Back (left), Test communication and Done (right, dark).
5.3 Test communication
Click Test communication at the bottom of the wizard. It reads the M-Tec Energy Butler GEN 3 once and saves nothing. If the test succeeds, 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.
Examples of the result for this device:
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Screenshot of a Test communication dialog in the Reduxi Configurator (close X at top right, dark Close button at bottom right). Green text in a white box: Successful readout from device. Battery active power: 330.0 W; Battery current: 0.9952 A; Battery export active energy: 740760.0 Wh; Battery import active energy: 765890.0 Wh; Battery max. active power: 8210.0 W; Battery max. state of charge: 100 %; Battery min. active power: -9131.0 W; Battery min. state of charge: 0.0 %; Battery state name: CHARGING null; Battery state of charge: 33.8 %; Battery state of health: 100.0 %; Battery temperature: 23.1 °C; Battery voltage: 331.6 V; Error: false null; Grid active power: 5.0 W; Grid export active energy: 1588740.0 Wh; Grid frequency: 50.01 Hz; Grid import active energy: 0.0 Wh; Grid state name: METER_ONLINE null; Inverter active power: -441.0 W; Inverter max. power: 10000.0 W; Inverter min. power: -10000.0 W; Load active power: 446.0 W; Load import active energy: 0.0 Wh; Model name: SigenStorEC100TP null; PV active power: -963.0 W; PV current: -1.99 A; PV export active energy: 0.0 Wh; PV min. active power: -10000.0 W; PV state name: CONNECTED null; PV voltage: 322.3 V; State name: RUNNING null. Additional parameters: BATTERY_CAPACITY_MAX_WH: 16120.0; BATTERY_CAPACITY_WH: 5448.56; GRID_EXPORT_POWER_ACTIVE: 0.0; GRID_IMPORT_POWER_ACTIVE: 5.0; GRID_POWER_ACTIVE_L1: 0.0; GRID_POWER_ACTIVE_L2: 5.0; GRID_POWER_ACTIVE_L3: 5.0 (partly cut off in the image); PV_POWER_ACTIVE_MAX: 0.
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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.
6 Check the readings
6.1 Last measurements
Check the measured values and the communication under Devices – M-Tec Energy Butler GEN 3 – Last Measurement in the Reduxi Configurator.
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Screenshot of the Reduxi Configurator 'Last measurements' page of a device. Tabs: Last measurements (active), Analyze, Archive. Top right: refresh dropdown 'Without refreshing' and a refresh button. Card 'Control type': buttons Auto (light green) and Manual (dark, selected); timestamp 14. 03. 2025 12:49:13. All values below have timestamp 14. 03. 2025 12:49:01 unless noted. Card PV: PV active power -1.0 kW; PV current -1.98 A; PV voltage 327.63 V; PV export active energy 587.0 kWh; PV min. active power -10.0 kW; PV export active power limit: empty (unit kW); enumeration.PV_STATE_NAME: CONNECTED. Card Load: Load active power 0.4 kW; Load import active energy 1,109.2 kWh. Card Battery: Battery active power 0.4 kW; Battery current 1.09 A; Battery voltage 331.60 V; Battery state name CHARGING; Battery state of charge 33.80 %; Battery min. state of charge 0.00 %; Battery max. state of charge 100.00 %; Battery import active energy 765.9 kWh; Battery export active energy 740.8 kWh; Battery min. active power -9.1 kW; Battery max. active power 8.2 kW; Battery active power setpoint 1.0 kW. Card Inverter: Inverter active power -0.4 kW; Inverter max. active power 10.0 kW; Inverter min. active power -10.0 kW; State name RUNNING; Error OFF. Card Grid: Grid frequency 49.990 Hz; Grid active power 0.0 kW; Grid import active power limit: empty (kW); Grid export active power limit: empty (kW); enumeration.GRID_STATE_NAME METER_ONLINE; Grid export active energy 1,588.7 kWh; Grid import active energy 0.0 kWh. Card Other: Battery state of health 100.00 %; Battery temperature 23.10 °C; Model name SigenStorEC100TP; Communication error OFF (timestamp 12:48:56); Control type MANUAL; Mode name setpoint SELF_CONSUMPTION.
6.2 Enable control by Reduxi
For advanced control, integrate the device into the optimization modes of the Reduxi system. Under Devices – M-Tec Energy Butler GEN 3 in the Reduxi Configurator, set the control type to AUTO. Only then do strategy commands affect the battery.
To achieve maximum flexibility and energy cost reduction with dynamic prices and dynamic tariffs, define a strategy as described in Strategies for Reduxi controller.
After you add the device, you can monitor and control it via the Reduxi application.
✓ Summary
Preparation (Points 1–2): Install the latest firmware. Connect the LAN module to COM 1. Connect the inverter and the Reduxi Controller to the router.
M-Tec Energy Butler GEN 3 (Point 3): Switch DHCP off on the display and set IP address, gateway address and subnet mask. Write the values down.
Add to Reduxi (Points 4–5): Log in to the Reduxi web interface, click + Add device, enter IP, port 502 and unit ID 255. Click Test communication, then Done.
Go live (Point 6): Check the last measurements. Set the control type to AUTO and define a strategy.
→ Common issues
| Issue | Solution |
|---|---|
| Modbus connection does not work | Install the latest firmware. It enables Modbus automatically. Contact M-Tec customer service for the update. |
| Display settings are not saved | Wait about 10 seconds after the last entry. The inverter then saves the settings. |
| Test communication fails | Check the IP address (Point 3), port 502 and the Modbus unit ID. The M-Tec default is 255. |
| 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 changed during installation. Ask the installer. The Reduxi account password does not work here. |
reduxi.local does not load |
Your device is not in the same network as the controller. Use the IP address or the tunnel connection. |
| Communication test fails, device shows offline | Check reachability, IP address / port / unit ID, and that the protocol is enabled on the device. |