diff --git a/app/models.py b/app/models.py
index c86b4ca..5eec88b 100644
--- a/app/models.py
+++ b/app/models.py
@@ -11,9 +11,10 @@ class NL43Config(Base):
 
     unit_id = Column(String, primary_key=True, index=True)
     host = Column(String, default="127.0.0.1")
-    tcp_port = Column(Integer, default=80)  # NL43 TCP control port (via RX55)
+    tcp_port = Column(Integer, default=2255)  # NL43 TCP control port (standard: 2255)
     tcp_enabled = Column(Boolean, default=True)
     ftp_enabled = Column(Boolean, default=False)
+    ftp_port = Column(Integer, default=21)  # FTP port (standard: 21)
     ftp_username = Column(String, nullable=True)  # FTP login username
     ftp_password = Column(String, nullable=True)  # FTP login password
     web_enabled = Column(Boolean, default=False)
diff --git a/app/routers.py b/app/routers.py
index 5d7cad4..4c7f37c 100644
--- a/app/routers.py
+++ b/app/routers.py
@@ -21,6 +21,7 @@ router = APIRouter(prefix="/api/nl43", tags=["nl43"])
 class ConfigPayload(BaseModel):
     host: str | None = None
     tcp_port: int | None = None
+    ftp_port: int | None = None
     tcp_enabled: bool | None = None
     ftp_enabled: bool | None = None
     ftp_username: str | None = None
@@ -44,7 +45,7 @@ class ConfigPayload(BaseModel):
                 raise ValueError("Host must be a valid IP address or hostname")
         return v
 
-    @field_validator("tcp_port")
+    @field_validator("tcp_port", "ftp_port")
     @classmethod
     def validate_port(cls, v):
         if v is None:
@@ -65,8 +66,11 @@ def get_config(unit_id: str, db: Session = Depends(get_db)):
             "unit_id": unit_id,
             "host": cfg.host,
             "tcp_port": cfg.tcp_port,
+            "ftp_port": cfg.ftp_port,
             "tcp_enabled": cfg.tcp_enabled,
             "ftp_enabled": cfg.ftp_enabled,
+            "ftp_username": cfg.ftp_username,
+            "ftp_password": cfg.ftp_password,
             "web_enabled": cfg.web_enabled,
         },
     }
@@ -83,6 +87,8 @@ def upsert_config(unit_id: str, payload: ConfigPayload, db: Session = Depends(ge
         cfg.host = payload.host
     if payload.tcp_port is not None:
         cfg.tcp_port = payload.tcp_port
+    if payload.ftp_port is not None:
+        cfg.ftp_port = payload.ftp_port
     if payload.tcp_enabled is not None:
         cfg.tcp_enabled = payload.tcp_enabled
     if payload.ftp_enabled is not None:
@@ -192,7 +198,7 @@ async def start_measurement(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.start()
         logger.info(f"Started measurement on unit {unit_id}")
@@ -235,7 +241,7 @@ async def stop_measurement(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.stop()
         logger.info(f"Stopped measurement on unit {unit_id}")
@@ -267,7 +273,7 @@ async def manual_store(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.manual_store()
         logger.info(f"Manual store executed on unit {unit_id}")
@@ -293,7 +299,7 @@ async def pause_measurement(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.pause()
         logger.info(f"Paused measurement on unit {unit_id}")
@@ -313,7 +319,7 @@ async def resume_measurement(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.resume()
         logger.info(f"Resumed measurement on unit {unit_id}")
@@ -333,7 +339,7 @@ async def reset_measurement(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.reset()
         logger.info(f"Reset measurement data on unit {unit_id}")
@@ -353,7 +359,7 @@ async def get_measurement_state(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         state = await client.get_measurement_state()
         is_measuring = state == "Start"
@@ -377,7 +383,7 @@ async def sleep_device(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.sleep()
         logger.info(f"Put device {unit_id} to sleep")
@@ -397,7 +403,7 @@ async def wake_device(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.wake()
         logger.info(f"Woke device {unit_id} from sleep")
@@ -417,7 +423,7 @@ async def get_sleep_status(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         status = await client.get_sleep_status()
         return {"status": "ok", "sleep_status": status}
@@ -436,7 +442,7 @@ async def get_battery(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         level = await client.get_battery_level()
         return {"status": "ok", "battery_level": level}
@@ -455,7 +461,7 @@ async def get_clock(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         clock = await client.get_clock()
         return {"status": "ok", "clock": clock}
@@ -478,7 +484,7 @@ async def set_clock(unit_id: str, payload: ClockPayload, db: Session = Depends(g
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_clock(payload.datetime)
         return {"status": "ok", "message": f"Clock set to {payload.datetime}"}
@@ -502,7 +508,7 @@ async def get_frequency_weighting(unit_id: str, channel: str = "Main", db: Sessi
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         weighting = await client.get_frequency_weighting(channel)
         return {"status": "ok", "frequency_weighting": weighting, "channel": channel}
@@ -521,7 +527,7 @@ async def set_frequency_weighting(unit_id: str, payload: WeightingPayload, db: S
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_frequency_weighting(payload.weighting, payload.channel)
         return {"status": "ok", "message": f"Frequency weighting set to {payload.weighting} on {payload.channel}"}
@@ -540,7 +546,7 @@ async def get_time_weighting(unit_id: str, channel: str = "Main", db: Session =
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         weighting = await client.get_time_weighting(channel)
         return {"status": "ok", "time_weighting": weighting, "channel": channel}
@@ -559,7 +565,7 @@ async def set_time_weighting(unit_id: str, payload: WeightingPayload, db: Sessio
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_time_weighting(payload.weighting, payload.channel)
         return {"status": "ok", "message": f"Time weighting set to {payload.weighting} on {payload.channel}"}
@@ -577,7 +583,7 @@ async def live_status(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         snap = await client.request_dod()
         snap.unit_id = unit_id
@@ -622,7 +628,7 @@ async def get_results(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         results = await client.request_dlc()
         logger.info(f"Retrieved measurement results for unit {unit_id}")
@@ -669,7 +675,7 @@ async def stream_live(websocket: WebSocket, unit_id: str):
             return
 
         # Create client and define callback
-        client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+        client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
 
         async def send_snapshot(snap):
             """Callback that sends each snapshot to the WebSocket client."""
@@ -746,7 +752,7 @@ async def enable_ftp(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.enable_ftp()
         logger.info(f"Enabled FTP on unit {unit_id}")
@@ -766,7 +772,7 @@ async def disable_ftp(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.disable_ftp()
         logger.info(f"Disabled FTP on unit {unit_id}")
@@ -786,7 +792,7 @@ async def get_ftp_status(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         status = await client.get_ftp_status()
         return {"status": "ok", "ftp_enabled": status.lower() == "on", "ftp_status": status}
@@ -810,7 +816,7 @@ async def get_latest_measurement_time(unit_id: str, db: Session = Depends(get_db
     if not cfg.ftp_enabled:
         raise HTTPException(status_code=403, detail="FTP is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         # List directories in the NL-43 folder
         items = await client.list_ftp_files("/NL-43")
@@ -864,7 +870,7 @@ async def get_all_settings(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         settings = await client.get_all_settings()
         logger.info(f"Retrieved all settings for unit {unit_id}")
@@ -892,7 +898,7 @@ async def list_ftp_files(unit_id: str, path: str = "/", db: Session = Depends(ge
     if not cfg:
         raise HTTPException(status_code=404, detail="NL43 config not found")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         files = await client.list_ftp_files(path)
         return {"status": "ok", "path": path, "files": files, "count": len(files)}
@@ -937,7 +943,7 @@ async def download_ftp_file(unit_id: str, payload: DownloadRequest, db: Session
 
     local_path = os.path.join(download_dir, filename)
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.download_ftp_file(payload.remote_path, local_path)
         logger.info(f"Downloaded {payload.remote_path} from {unit_id} to {local_path}")
@@ -968,7 +974,7 @@ async def get_measurement_time(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         preset = await client.get_measurement_time()
         return {"status": "ok", "measurement_time": preset}
@@ -987,7 +993,7 @@ async def set_measurement_time(unit_id: str, payload: TimingPayload, db: Session
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_measurement_time(payload.preset)
         return {"status": "ok", "message": f"Measurement time set to {payload.preset}"}
@@ -1006,7 +1012,7 @@ async def get_leq_interval(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         preset = await client.get_leq_interval()
         return {"status": "ok", "leq_interval": preset}
@@ -1025,7 +1031,7 @@ async def set_leq_interval(unit_id: str, payload: TimingPayload, db: Session = D
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_leq_interval(payload.preset)
         return {"status": "ok", "message": f"Leq interval set to {payload.preset}"}
@@ -1044,7 +1050,7 @@ async def get_lp_interval(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         preset = await client.get_lp_interval()
         return {"status": "ok", "lp_interval": preset}
@@ -1063,7 +1069,7 @@ async def set_lp_interval(unit_id: str, payload: TimingPayload, db: Session = De
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_lp_interval(payload.preset)
         return {"status": "ok", "message": f"Lp interval set to {payload.preset}"}
@@ -1082,7 +1088,7 @@ async def get_index_number(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         index = await client.get_index_number()
         return {"status": "ok", "index_number": index}
@@ -1101,7 +1107,7 @@ async def set_index_number(unit_id: str, payload: IndexPayload, db: Session = De
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         await client.set_index_number(payload.index)
         return {"status": "ok", "message": f"Index number set to {payload.index:04d}"}
@@ -1129,7 +1135,7 @@ async def check_overwrite_status(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         overwrite_status = await client.get_overwrite_status()
         will_overwrite = overwrite_status == "Exist"
@@ -1154,7 +1160,7 @@ async def get_all_settings(unit_id: str, db: Session = Depends(get_db)):
     if not cfg.tcp_enabled:
         raise HTTPException(status_code=403, detail="TCP communication is disabled for this device")
 
-    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password)
+    client = NL43Client(cfg.host, cfg.tcp_port, ftp_username=cfg.ftp_username, ftp_password=cfg.ftp_password, ftp_port=cfg.ftp_port or 21)
     try:
         settings = await client.get_all_settings()
         return {"status": "ok", "settings": settings}
diff --git a/app/services.py b/app/services.py
index b956454..33709c3 100644
--- a/app/services.py
+++ b/app/services.py
@@ -105,12 +105,13 @@ _rate_limit_lock = asyncio.Lock()
 
 
 class NL43Client:
-    def __init__(self, host: str, port: int, timeout: float = 5.0, ftp_username: str = None, ftp_password: str = None):
+    def __init__(self, host: str, port: int, timeout: float = 5.0, ftp_username: str = None, ftp_password: str = None, ftp_port: int = 21):
         self.host = host
         self.port = port
         self.timeout = timeout
-        self.ftp_username = ftp_username or "anonymous"
-        self.ftp_password = ftp_password or ""
+        self.ftp_username = ftp_username or "USER"
+        self.ftp_password = ftp_password or "0000"
+        self.ftp_port = ftp_port
         self.device_key = f"{host}:{port}"
 
     async def _enforce_rate_limit(self):
@@ -717,14 +718,17 @@ class NL43Client:
         logger.info(f"Listing FTP files on {self.device_key} at {remote_path}")
 
         def _list_ftp_sync():
-            """Synchronous FTP listing using ftplib (supports active mode)."""
+            """Synchronous FTP listing using ftplib for NL-43 devices."""
             ftp = FTP()
-            ftp.set_debuglevel(0)
+            ftp.set_debuglevel(2)  # Enable FTP debugging
             try:
                 # Connect and login
-                ftp.connect(self.host, 21, timeout=10)
+                logger.info(f"Connecting to FTP server at {self.host}:{self.ftp_port}")
+                ftp.connect(self.host, self.ftp_port, timeout=10)
+                logger.info(f"Logging in with username: {self.ftp_username}")
                 ftp.login(self.ftp_username, self.ftp_password)
-                ftp.set_pasv(False)  # Force active mode
+                ftp.set_pasv(False)  # Use active mode (required for NL-43 devices)
+                logger.info("FTP connection established in active mode")
 
                 # Change to target directory
                 if remote_path != "/":
@@ -824,7 +828,7 @@ class NL43Client:
             ftp.set_debuglevel(0)
             try:
                 # Connect and login
-                ftp.connect(self.host, 21, timeout=10)
+                ftp.connect(self.host, self.ftp_port, timeout=10)
                 ftp.login(self.ftp_username, self.ftp_password)
                 ftp.set_pasv(False)  # Force active mode
 
diff --git a/migrate_add_ftp_port.py b/migrate_add_ftp_port.py
new file mode 100644
index 0000000..406fb48
--- /dev/null
+++ b/migrate_add_ftp_port.py
@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+"""
+Migration script to add ftp_port column to nl43_config table.
+
+Usage:
+    python migrate_add_ftp_port.py
+"""
+
+import sqlite3
+import sys
+from pathlib import Path
+
+def migrate():
+    db_path = Path("data/slmm.db")
+
+    if not db_path.exists():
+        print(f"❌ Database not found at {db_path}")
+        print("   Run this script from the slmm directory")
+        return False
+
+    try:
+        conn = sqlite3.connect(db_path)
+        cursor = conn.cursor()
+
+        # Check if column already exists
+        cursor.execute("PRAGMA table_info(nl43_config)")
+        columns = [row[1] for row in cursor.fetchall()]
+
+        if "ftp_port" in columns:
+            print("✓ ftp_port column already exists")
+            conn.close()
+            return True
+
+        print("Adding ftp_port column to nl43_config table...")
+
+        # Add the ftp_port column with default value of 21
+        cursor.execute("""
+            ALTER TABLE nl43_config
+            ADD COLUMN ftp_port INTEGER DEFAULT 21
+        """)
+
+        conn.commit()
+        print("✓ Migration completed successfully")
+        print("  Added ftp_port column (default: 21)")
+
+        conn.close()
+        return True
+
+    except Exception as e:
+        print(f"❌ Migration failed: {e}")
+        return False
+
+if __name__ == "__main__":
+    success = migrate()
+    sys.exit(0 if success else 1)