diff --git a/apps/mosquito/api/serializers.py b/apps/mosquito/api/serializers.py
index dbdbace..bca897b 100644
--- a/apps/mosquito/api/serializers.py
+++ b/apps/mosquito/api/serializers.py
@@ -80,6 +80,7 @@ class WeatherLogSerializer(serializers.ModelSerializer):
         ]
 
     def get_power(self, obj):
+        # power max 12.6V, min 8.5V
         power = int((float(obj.power) - 8.5) / 4.1 * 100)
         return str(power)
     def get_data_time(self, obj):