diff --git a/homeassistant/components/saj/sensor.py b/homeassistant/components/saj/sensor.py
index 795823b9e9fff53f0bef62b8ad2974f5edec8b82..8e59899de272525aa22448c2c81f49a1ba5ca381 100644
--- a/homeassistant/components/saj/sensor.py
+++ b/homeassistant/components/saj/sensor.py
@@ -10,6 +10,7 @@ import voluptuous as vol
 from homeassistant.components.sensor import (
     PLATFORM_SCHEMA,
     STATE_CLASS_MEASUREMENT,
+    STATE_CLASS_TOTAL_INCREASING,
     SensorEntity,
 )
 from homeassistant.const import (
@@ -34,7 +35,6 @@ from homeassistant.core import CALLBACK_TYPE, callback
 from homeassistant.exceptions import PlatformNotReady
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.event import async_call_later
-from homeassistant.util import dt as dt_util
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -177,10 +177,10 @@ class SAJsensor(SensorEntity):
         self._serialnumber = serialnumber
         self._state = self._sensor.value
 
-        if pysaj_sensor.name in ("current_power", "total_yield", "temperature"):
+        if pysaj_sensor.name in ("current_power", "temperature"):
             self._attr_state_class = STATE_CLASS_MEASUREMENT
         if pysaj_sensor.name == "total_yield":
-            self._attr_last_reset = dt_util.utc_from_timestamp(0)
+            self._attr_state_class = STATE_CLASS_TOTAL_INCREASING
 
     @property
     def name(self):