diff --git a/custom_components/ocpp/__init__.py b/custom_components/ocpp/__init__.py
index 70614747..cfbce73b 100644
--- a/custom_components/ocpp/__init__.py
+++ b/custom_components/ocpp/__init__.py
@@ -8,7 +8,7 @@
 from homeassistant.helpers import device_registry
 
 from .api import CentralSystem
-from .const import CONF_CPID, CONF_CSID, DOMAIN, PLATFORMS
+from .const import CONF_CPID, CONF_CSID, DEFAULT_CPID, DEFAULT_CSID, DOMAIN, PLATFORMS
 
 _LOGGER: logging.Logger = logging.getLogger(__package__)
 logging.getLogger(DOMAIN).setLevel(logging.DEBUG)
@@ -32,16 +32,16 @@ async def async_setup_entry(hass: HomeAssistant, entry: ConfigEntry):
     """ Create Central System Device """
     dr.async_get_or_create(
         config_entry_id=entry.entry_id,
-        identifiers={(DOMAIN, entry.data[CONF_CSID])},
-        name=entry.data[CONF_CSID],
+        identifiers={(DOMAIN, entry.data.get(CONF_CSID, DEFAULT_CSID))},
+        name=entry.data.get(CONF_CSID, DEFAULT_CSID),
         model="OCPP Central System",
     )
 
     """ Create Charge Point Device """
     dr.async_get_or_create(
         config_entry_id=entry.entry_id,
-        identifiers={(DOMAIN, entry.data[CONF_CPID])},
-        name=entry.data[CONF_CPID],
+        identifiers={(DOMAIN, entry.data.get(CONF_CPID, DEFAULT_CPID))},
+        name=entry.data.get(CONF_CPID, DEFAULT_CPID),
         default_model="OCPP Charge Point",
         via_device=((DOMAIN), central_sys.id),
     )
diff --git a/custom_components/ocpp/sensor.py b/custom_components/ocpp/sensor.py
index 69e5cdb0..54f355aa 100644
--- a/custom_components/ocpp/sensor.py
+++ b/custom_components/ocpp/sensor.py
@@ -1,17 +1,29 @@
 """Sensor platform for ocpp."""
 
-from homeassistant.const import CONF_MONITORED_VARIABLES
-from homeassistant.helpers.entity import Entity
+import datetime
+
+import homeassistant
+from homeassistant.components.sensor import STATE_CLASS_MEASUREMENT, SensorEntity
+from homeassistant.const import (
+    CONF_MONITORED_VARIABLES,
+    DEVICE_CLASS_CURRENT,
+    DEVICE_CLASS_ENERGY,
+    DEVICE_CLASS_POWER,
+    DEVICE_CLASS_TEMPERATURE,
+    DEVICE_CLASS_VOLTAGE,
+)
+
+from ocpp.v16.enums import UnitOfMeasure
 
 from .api import CentralSystem
-from .const import CONF_CPID, DOMAIN, ICON
+from .const import CONF_CPID, DEFAULT_CPID, DOMAIN, ICON
 from .enums import HAChargerDetails, HAChargerSession, HAChargerStatuses
 
 
 async def async_setup_entry(hass, entry, async_add_devices):
     """Configure the sensor platform."""
     central_system = hass.data[DOMAIN][entry.entry_id]
-    cp_id = entry.data[CONF_CPID]
+    cp_id = entry.data.get(CONF_CPID, DEFAULT_CPID)
 
     entities = []
 
@@ -36,7 +48,7 @@ async def async_setup_entry(hass, entry, async_add_devices):
     async_add_devices(entities, False)
 
 
-class ChargePointMetric(Entity):
+class ChargePointMetric(SensorEntity):
     """Individual sensor for charge point metrics."""
 
     def __init__(
@@ -51,6 +63,7 @@ def __init__(
         self.metric = metric
         self._state = None
         self._extra_attr = {}
+        self._last_reset = homeassistant.util.dt.utc_from_timestamp(0)
 
     @property
     def name(self):
@@ -65,7 +78,17 @@ def unique_id(self):
     @property
     def state(self):
         """Return the state of the sensor."""
-        return self.central_system.get_metric(self.cp_id, self.metric)
+        old_state = self._state
+        new_state = self.central_system.get_metric(self.cp_id, self.metric)
+        self._state = new_state
+        if (
+            (self.device_class is DEVICE_CLASS_ENERGY)
+            and (new_state is not None)
+            and (old_state is not None)
+            and (new_state < old_state)
+        ):
+            self._last_reset = datetime.datetime.now()
+        return self._state
 
     @property
     def available(self) -> bool:
@@ -103,6 +126,41 @@ def extra_state_attributes(self):
         """Return the state attributes."""
         return self.central_system.get_extra_attr(self.cp_id, self.metric)
 
+    @property
+    def state_class(self):
+        """Return the state class of the sensor."""
+        return STATE_CLASS_MEASUREMENT
+
+    @property
+    def device_class(self):
+        """Return the device class of the sensor."""
+        if self.unit_of_measurement in [
+            UnitOfMeasure.wh.value,
+            UnitOfMeasure.kwh.value,
+        ]:
+            return DEVICE_CLASS_ENERGY
+        elif self.unit_of_measurement in [
+            UnitOfMeasure.w.value,
+            UnitOfMeasure.kw.value,
+        ]:
+            return DEVICE_CLASS_POWER
+        elif self.unit_of_measurement in [
+            UnitOfMeasure.celsius.value,
+            UnitOfMeasure.fahrenheit.value,
+        ]:
+            return DEVICE_CLASS_TEMPERATURE
+        elif self.unit_of_measurement in [UnitOfMeasure.a.value]:
+            return DEVICE_CLASS_CURRENT
+        elif self.unit_of_measurement in [UnitOfMeasure.v.value]:
+            return DEVICE_CLASS_VOLTAGE
+        else:
+            return None
+
+    @property
+    def last_reset(self):
+        """Return the time when a metered value wwas ;ast reset."""
+        return self._last_reset
+
     async def async_update(self):
         """Get the latest data and update the states."""
         pass
diff --git a/custom_components/ocpp/switch.py b/custom_components/ocpp/switch.py
index dd0f3a51..9fe1d108 100644
--- a/custom_components/ocpp/switch.py
+++ b/custom_components/ocpp/switch.py
@@ -4,13 +4,13 @@
 from homeassistant.components.switch import SwitchEntity
 
 from .api import CentralSystem
-from .const import CONF_CPID, DOMAIN, ICON, SWITCHES
+from .const import CONF_CPID, DEFAULT_CPID, DOMAIN, ICON, SWITCHES
 
 
 async def async_setup_entry(hass, entry, async_add_devices):
     """Configure the sensor platform."""
     central_system = hass.data[DOMAIN][entry.entry_id]
-    cp_id = entry.data[CONF_CPID]
+    cp_id = entry.data.get(CONF_CPID, DEFAULT_CPID)
 
     entities = []