⚡ Reduxi Controller · Knowledge Base
How to add Fronius Wattpilot via OCPP
Connect the Fronius Wattpilot wallbox to the Reduxi Controller via OCPP 1.6J, so that the Controller can monitor and control charging with PV surplus and load management.
Fronius Wattpilot – wall-mounted version
Fronius Wattpilot – portable version with CEE plug
📋 In this article
1 Technical documentation
The Fronius Wattpilot supports OCPP 1.6J (Open Charge Point Protocol, JSON over WebSocket). In this setup the Reduxi Controller acts as the local OCPP server (central system) and the Wattpilot connects to it as a charge point – no cloud service is needed.
Protocol
OCPP 1.6J
Connection
WebSocket
ws:// (local)Network
LAN / Wi‑Fi via router
Device identifier
Wattpilot serial number
Smart charging
Charging profiles in A
Phase switching
3 → 1 phase supported
Manufacturer documents:
- Fronius Wattpilot OCPP – User Information (42,0410,2881) – supported OCPP messages, configuration parameters and activation in the app
-
Open Charge Alliance – OCPP 1.6 specification:
https://www.openchargealliance.org/
Supported OCPP functions Authorize, BootNotification, Heartbeat, MeterValues, Start/StopTransaction, StatusNotification as well as RemoteStart/Stop, SetChargingProfile, ClearChargingProfile, TriggerMessage, UnlockConnector, Reset and UpdateFirmware. Feature profiles: Core, FirmwareManagement, SmartCharging, RemoteTrigger.
2 Required equipment
- Fronius Wattpilot, installed and commissioned by a qualified electrician
- Wattpilot connected to the same local network as the Reduxi Controller (Wi‑Fi or LAN via router)
- Smartphone with the Fronius Solar.wattpilot app, connected to the Wattpilot
- Reduxi Controller with a known, fixed IP address (e.g.
192.168.31.73) – shown in the Reduxi Configurator as Controller OCPP JSON 1.6 URL when you add the device, or in the router - Serial number of the Wattpilot (shown in the app and on the type plate, e.g.
91099800) - Laptop or tablet with internet access for the Reduxi Configurator
Fixed IP address for the Controller The Wattpilot connects to the Controller’s IP address. If the router assigns a new address, the OCPP connection is lost. Reserve the IP of the Reduxi Controller in the router (DHCP reservation).
3 System overview
The Wattpilot opens a WebSocket connection to the Reduxi Controller and identifies itself with its serial number. The Controller assigns the connection to the device with the same device identifier and then reads measurements and sends charging limits.
| Component | Role | Address / setting |
|---|---|---|
| Reduxi Controller | OCPP server (central system) | ws://<Controller IP>/ocpp/1.6/json |
| Fronius Wattpilot | OCPP client (charge point) | Connects to the URL above + its serial number |
| Full URL used by the Wattpilot | – | ws://192.168.31.73/ocpp/1.6/json/91099800 |
Unencrypted connection in the local network For a local server the Wattpilot allows
ws:// (unencrypted) or wss://. The Reduxi Controller uses ws://. External OCPP servers always require wss://.4 Configure OCPP in the Wattpilot app
4.1 Enable OCPP
1
Open the app
Start the Fronius Solar.wattpilot app and connect to the Wattpilot.
2
Open the OCPP settings
Open the Internet tab and tap OCPP (in newer app versions: Einstellungen → OCPP).
3
Enable OCPP 1.6J
Switch on OCPP1.6J. OCPP automatically activates access management on the Wattpilot.
Internet menu with the OCPP entry (Fronius Solar.wattpilot app)
4.2 OCPP server settings
Tap OCPP-Server and enter the following values:
| Field (DE / EN) | Value |
|---|---|
| Protokoll / Protocol | WS |
| Benutzername / User | empty |
| Passwort / Password | empty |
| Host | IP address of the Reduxi Controller, e.g. 192.168.31.73
|
| Pfad / Path | /ocpp/1.6/json/ |
| SN zur URL hinzufügen / Add SN to URL | On – mandatory |
“SN zur URL hinzufügen / Add SN to URL” must be switched on Without this option the Wattpilot does not add its serial number to the URL, the Controller cannot identify it and no communication is established. Always check that the switch is green before saving.
The app then shows the complete address, e.g. ws://192.168.31.73/ocpp/1.6/json/91099800. Tap Änderungen speichern / Save. The Controller URL is also shown in the Reduxi Configurator (see Point 6.2).
Status not “Connected” yet? That is expected The Wattpilot is only accepted once it has been added in Reduxi with its serial number. Continue with Point 5 and Point 6 – afterwards the status changes to Verbunden / Connected. Tip: if you don’t know the Controller IP yet, do Point 6 first and copy the address from the field Controller OCPP JSON 1.6 URL.
OCPP menu: OCPP1.6J enabled, status “Verbunden” (connected)
OCPP server: protocol WS, host = Controller IP, path /ocpp/1.6/json/, SN added to URL
4.3 Further OCPP options
| Option | Recommendation |
|---|---|
| Status | Shows Not connected, Started, Connected or Connected and accepted. After adding the device in Reduxi it must show Verbunden / Connected. |
| Fallback-Strom / Fallback current | Charging current the Wattpilot uses if the OCPP connection to the Controller is lost. Set a value that is safe for the house connection. |
| Phasenzuordnung / Phase assignment | Assignment of the Wattpilot phases to the grid phases (e.g. L1 L2 L3). Must match the wiring so that load management reduces the right phase. |
| Alternative ID, Netzwerksicherheit, Erweiterte Einstellungen | Leave unchanged. |
5 Log in to the Reduxi web interface
The Reduxi Configurator can be opened remotely via the tunnel connection in the Reduxi app or locally in a web browser in the same network. Both lead to the same web interface.
Remote
Reduxi app
Via tunnel connection · works from anywhere
Web browser
In the local network · via IP address or reduxi.local
📱 5.1 Remote via the Reduxi app (tunnel)
1
Open the app and log in
Launch the Reduxi app on your smartphone or tablet and log in with your credentials.
2
Open Reduxi devices
Tap the menu icon (three lines, top left) and select Reduxi devices.
3
Activate the tunnel connection
Switch on the tunnel connection and wait a moment until it is active.
4
Open the configurator
Tap Open configurator. The Reduxi web interface opens.
Activate the tunnel connection
Open configurator
🖥️ 5.2 Locally via a web browser
1
Open the login page
On a device in the same network, open a web browser and enter the Controller’s IP address (e.g.
http://192.168.31.73) or http://reduxi.local.2
Log in
Username:
admin · Password: admin (factory default).Reduxi Controller login screen
Web interface after login
The Wattpilot always connects locally Regardless of how you open the Configurator, the Wattpilot itself always connects to the Controller in the local network via
ws://<Controller IP>/ocpp/1.6/json.6 Add the Wattpilot to Reduxi
6.1 Basic settings
1
Add a new device
In the left menu under Devices click + Add device.
2
Select type
Device type:
EV charger · Type: OCPP 1.6 - JSON.3
Name and strategy
Enter a Name (e.g.
Fronius Wattpilot). Under Include to strategy keep Energy manager → Regulated devices ticked, then click Next.
Click + Add device in the left menu
Device type EV charger, type OCPP 1.6 - JSON, name and strategy
6.2 Communication settings
| Field | Value |
|---|---|
| Device identifier |
Serial number of the Wattpilot, e.g. 91099800 – exactly the number at the end of the URL in the app |
| Connector | 1 |
| Charger type | AC |
| Energy counter | Default |
| Allocate power to EVSE when EV is not connected | Default |
| Per phase max. current |
Auto detect from EVSE or Manual override with the fused current, e.g. 32 A (22 kW) or 16 A (11 kW) |
| Forward communication / username / password / measurements to backend OCPP server | empty – only needed if an external OCPP backend is used in parallel |
| Allow new charging session | Always |
| Controller OCPP JSON 1.6 URL | read only, e.g. ws://192.168.31.73/ocpp/1.6/json – this is the address entered in the app (see Point 4.2) |
Device identifier = serial number of the Wattpilot Enter the serial number of the Wattpilot as Device identifier – it is shown in the app header (e.g.
Wattpilot_91099800 → 91099800) and at the end of the OCPP URL. Without the correct identifier the Controller cannot assign the incoming OCPP connection and shows no data.
Device identifier = serial number of the Wattpilot, connector 1, AC
Check the values and click Done to save the device.
Controller OCPP JSON 1.6 URL – click Done to save the device
6.3 Test communication
With OCPP the Wattpilot connects to the Controller by itself – no IP address of the Wattpilot is needed. Open the device again (Devices → [Wattpilot] → Details) and click Test communication at the bottom right.
“Unable to communicate with device” is normal for OCPP With OCPP the Controller cannot actively ping the charger – the Wattpilot connects to the Controller by itself. The red line in the first box can therefore be ignored. What matters is the box below: Number of devices found must be at least
1 and the Device identifier must show the serial number of the Wattpilot. The final proof are the live values under Last measurements.
Test communication: the window lists the chargers connected via OCPP and their device identifiers
- Number of devices found on OCPP – JSON 1.6 shows how many chargers are connected to the Controller via OCPP.
-
Device identifier must show the serial number of the Wattpilot (e.g.
91099800). If it does not appear, the Wattpilot is not connected – check the app settings (see Point 4.2). - In the Wattpilot app the OCPP status must show Verbunden / Connected.
- Final check: live values and Communication error =
OFF(see Point 7).
Connection established If both sides show a connection, the Wattpilot is ready. The Reduxi Controller now controls the charging current according to the active strategy.
7 Check the readings
Open Devices → [Wattpilot] → Last measurements:
Last measurements: control type, currents per phase, power, energy and charger state
| Value | Meaning |
|---|---|
| Control type |
Auto = controlled by the Reduxi strategy · Manual · Off
|
| Current L1 / L2 / L3 | Charging current per phase |
| Max. current per phase | Maximum current of the charger (e.g. 32 A) |
| Active power / Max. active power | Current charging power and maximum power (e.g. 22.1 kW) |
| Import active energy / session | Total charged energy and energy of the current session |
| Communication error | Must be OFF
|
| State name | Current state of the charger, e.g. AVAILABLE when no car is connected |
✓ Summary
Preparation (Points 1–3): Wattpilot and Reduxi Controller in the same network, Controller with fixed IP, serial number of the Wattpilot at hand.
Wattpilot app (Point 4): enable OCPP1.6J, protocol WS, host = Controller IP, path /ocpp/1.6/json/, “SN zur URL hinzufügen” on (mandatory).
Add to Reduxi (Points 5–6): EV charger · OCPP 1.6 - JSON, device identifier = serial number, connector 1, AC.
Go live (Point 7): app shows “Connected”, Reduxi shows live values and communication error OFF.
→ Common issues
| Issue | Solution |
|---|---|
| App status stays “Started” / “Not connected” | Check that “SN zur URL hinzufügen” is on, then host (Controller IP), protocol WS (not WSS), path /ocpp/1.6/json/ and that both devices are in the same network. |
| App shows “Connected”, but Reduxi shows no data | The device identifier in Reduxi must match the serial number at the end of the URL exactly (e.g. 91099800). “SN zur URL hinzufügen” must be on. |
| Connection lost after a router restart | The Controller got a new IP address. Reserve a fixed IP in the router and update the host in the app. |
| Unwanted charging behaviour when the Controller is offline | Set a Fallback current in the app’s OCPP menu (see Point 4.3). |
| Load management reduces the wrong phase | Check the phase assignment in the app and in Reduxi (Advanced configuration → “L1/L2/L3 is connected to main feed”). |
| Car does not start charging | OCPP activates access management – check Allow new charging session = Always in Reduxi. |