diff --git a/apps/iot/src/iot_device.erl b/apps/iot/src/iot_device.erl
index 57bd8a9..779aebb 100644
--- a/apps/iot/src/iot_device.erl
+++ b/apps/iot/src/iot_device.erl
@@ -188,7 +188,7 @@ report_event(DeviceUUID, NewStatus) when is_binary(DeviceUUID), is_integer(NewSt
     FieldsList = [#{
         <<"key">> => <<"device_status">>,
         <<"value">> => NewStatus,
-        <<"unit">> => <<"">>,
+        <<"unit">> => 0,
         <<"type">> => <<"DI">>,
         <<"name">> => <<"设备状态"/utf8>>,
         <<"timestamp">> => Timestamp
diff --git a/apps/iot/src/iot_host.erl b/apps/iot/src/iot_host.erl
index f195fbe..14df359 100644
--- a/apps/iot/src/iot_host.erl
+++ b/apps/iot/src/iot_host.erl
@@ -533,7 +533,7 @@ report_event(UUID, NewStatus) when is_binary(UUID), is_integer(NewStatus) ->
     FieldsList = [#{
         <<"key">> => <<"host_status">>,
         <<"value">> => NewStatus,
-        <<"unit">> => <<"">>,
+        <<"unit">> => 0,
         <<"type">> => <<"DI">>,
         <<"name">> => <<"主机状态"/utf8>>,
         <<"timestamp">> => Timestamp