diff --git a/packages/modules/devices/sma/sma_sunny_boy/bat.py b/packages/modules/devices/sma/sma_sunny_boy/bat.py
index da50bc7673..99624e1295 100644
--- a/packages/modules/devices/sma/sma_sunny_boy/bat.py
+++ b/packages/modules/devices/sma/sma_sunny_boy/bat.py
@@ -12,6 +12,8 @@
 
 
 class SunnyBoyBat(AbstractBat):
+    SMA_UINT_64_NAN = 0xFFFFFFFFFFFFFFFF  # SMA uses this value to represent NaN
+
     def __init__(self,
                  device_id: int,
                  component_config: Union[Dict, SmaSunnyBoyBatSetup],
@@ -35,6 +37,11 @@ def read(self) -> BatState:
         exported = self.__tcp_client.read_holding_registers(31401, ModbusDataType.UINT_64, unit=unit)
         imported = self.__tcp_client.read_holding_registers(31397, ModbusDataType.UINT_64, unit=unit)
 
+        if exported == self.SMA_UINT_64_NAN or imported == self.SMA_UINT_64_NAN:
+            raise ValueError(f'Batterie lieferte nicht plausible Werte. Export: {exported}, Import: {imported}. ',
+                             'Sobald die Batterie geladen/entladen wird sollte sich dieser Wert ändern, ',
+                             'andernfalls kann ein Defekt vorliegen.')
+
         return BatState(
             power=power,
             soc=soc,
diff --git a/packages/modules/devices/sma/sma_sunny_boy/bat_smart_energy.py b/packages/modules/devices/sma/sma_sunny_boy/bat_smart_energy.py
index b80e0864d7..b5b5d61845 100644
--- a/packages/modules/devices/sma/sma_sunny_boy/bat_smart_energy.py
+++ b/packages/modules/devices/sma/sma_sunny_boy/bat_smart_energy.py
@@ -13,7 +13,8 @@
 
 
 class SunnyBoySmartEnergyBat(AbstractBat):
-    SMA_INT32_NAN = 0xFFFFFFFF  # SMA uses this value to represent NaN
+    SMA_UINT32_NAN = 0xFFFFFFFF  # SMA uses this value to represent NaN
+    SMA_UINT_64_NAN = 0xFFFFFFFFFFFFFFFF  # SMA uses this value to represent NaN
 
     def __init__(self,
                  device_id: int,
@@ -36,7 +37,7 @@ def read(self) -> BatState:
         current = self.__tcp_client.read_holding_registers(30843, ModbusDataType.INT_32, unit=unit)/-1000
         voltage = self.__tcp_client.read_holding_registers(30851, ModbusDataType.INT_32, unit=unit)/100
 
-        if soc == self.SMA_INT32_NAN:
+        if soc == self.SMA_UINT32_NAN:
             # If the storage is empty and nothing is produced on the DC side, the inverter does not supply any values.
             soc = 0
             power = 0
@@ -45,6 +46,11 @@ def read(self) -> BatState:
         exported = self.__tcp_client.read_holding_registers(31401, ModbusDataType.UINT_64, unit=3)
         imported = self.__tcp_client.read_holding_registers(31397, ModbusDataType.UINT_64, unit=3)
 
+        if exported == self.SMA_UINT_64_NAN or imported == self.SMA_UINT_64_NAN:
+            raise ValueError(f'Batterie lieferte nicht plausible Werte. Export: {exported}, Import: {imported}. ',
+                             'Sobald die Batterie geladen/entladen wird sollte sich dieser Wert ändern, ',
+                             'andernfalls kann ein Defekt vorliegen.')
+
         return BatState(
             power=power,
             soc=soc,
diff --git a/packages/modules/devices/sma/sma_sunny_boy/inverter.py b/packages/modules/devices/sma/sma_sunny_boy/inverter.py
index ee2a81b4c9..8685fd7410 100644
--- a/packages/modules/devices/sma/sma_sunny_boy/inverter.py
+++ b/packages/modules/devices/sma/sma_sunny_boy/inverter.py
@@ -19,6 +19,7 @@
 class SmaSunnyBoyInverter(AbstractInverter):
 
     SMA_INT32_NAN = -0x80000000  # SMA uses this value to represent NaN
+    SMA_UINT32_NAN = 0xFFFFFFFF  # SMA uses this value to represent NaN
     SMA_NAN = -0xC000
 
     def __init__(self,
@@ -68,6 +69,13 @@ def read(self) -> InverterState:
         if power_total == self.SMA_INT32_NAN or power_total == self.SMA_NAN:
             power_total = 0
 
+        if energy == self.SMA_UINT32_NAN:
+            raise ValueError(
+                f'Wechselrichter lieferte nicht plausiblen Zählerstand: {energy}. '
+                'Sobald PV Ertrag vorhanden ist sollte sich dieser Wert ändern, '
+                'andernfalls kann ein Defekt vorliegen.'
+            )
+
         inverter_state = InverterState(
             power=power_total * -1,
             dc_power=dc_power * -1,