diff --git a/src/rpi-cpu2mqtt.py b/src/rpi-cpu2mqtt.py
index 65b06ac..8386502 100644
--- a/src/rpi-cpu2mqtt.py
+++ b/src/rpi-cpu2mqtt.py
@@ -293,6 +293,7 @@ def config_json(what_config):
         data["state_class"] = "measurement"
         data["payload_on"] = "on"
         data["payload_off"] = "off"
+        data["device_class"] = "update"
     else:
         return ""
     # Return our built discovery config