diff --git a/src/telemetry.rs b/src/telemetry.rs
index 79c1ddf..3cba9ed 100644
--- a/src/telemetry.rs
+++ b/src/telemetry.rs
@@ -4,6 +4,20 @@ use uuid::Uuid;
 
 use crate::model::ScanMode;
 
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "snake_case")]
+pub enum ValueType {
+    Null,
+    Bool,
+    Int,
+    UInt,
+    Float,
+    Text,
+    Bytes,
+    Array,
+    Object,
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
 #[serde(rename_all = "snake_case")]
 pub enum PointQuality {
@@ -69,7 +83,7 @@ pub struct PointMonitorInfo {
     pub timestamp: Option<DateTime<Utc>>,
     pub quality: PointQuality,
     pub value: Option<DataValue>,
-    pub value_type: Option<String>,
+    pub value_type: Option<ValueType>,
     pub value_text: Option<String>,
 }
 
@@ -85,7 +99,7 @@ pub struct PointValueChangeEvent {
     pub point_id: Option<Uuid>,
     pub client_handle: u32,
     pub value: Option<DataValue>,
-    pub value_type: Option<String>,
+    pub value_type: Option<ValueType>,
     pub value_text: Option<String>,
     pub quality: PointQuality,
     pub protocol: String,
@@ -101,7 +115,7 @@ pub struct WsPointMonitorInfo {
     pub timestamp: Option<String>,
     pub quality: PointQuality,
     pub value: Option<serde_json::Value>,
-    pub value_type: Option<String>,
+    pub value_type: Option<ValueType>,
 }
 
 impl From<&PointMonitorInfo> for WsPointMonitorInfo {
@@ -146,9 +160,17 @@ pub fn opcua_variant_to_data(value: &opcua::types::Variant) -> DataValue {
     }
 }
 
-pub fn opcua_variant_type(value: &opcua::types::Variant) -> String {
-    match value.scalar_type_id() {
-        Some(t) => t.to_string(),
-        None => "unknown".to_string(),
+pub fn opcua_variant_type(value: &opcua::types::Variant) -> ValueType {
+    use opcua::types::Variant;
+    match value {
+        Variant::Empty => ValueType::Null,
+        Variant::Boolean(_) => ValueType::Bool,
+        Variant::SByte(_) | Variant::Int16(_) | Variant::Int32(_) | Variant::Int64(_) => ValueType::Int,
+        Variant::Byte(_) | Variant::UInt16(_) | Variant::UInt32(_) | Variant::UInt64(_) => ValueType::UInt,
+        Variant::Float(_) | Variant::Double(_) => ValueType::Float,
+        Variant::String(_) => ValueType::Text,
+        Variant::ByteString(_) => ValueType::Bytes,
+        Variant::Array(_) => ValueType::Array,
+        _ => ValueType::Text,
     }
 }