diff --git a/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT/AdsTwinCATClient.cs b/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT/AdsTwinCATClient.cs
index 385b37e6..245ce4c8 100644
--- a/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT/AdsTwinCATClient.cs
+++ b/src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT/AdsTwinCATClient.cs
@@ -376,27 +376,36 @@ internal sealed class AdsTwinCATClient : ITwinCATClient
         return (MapSymbolTypeName(dataType.Name), null);
     }
 
-    private static TwinCATDataType? MapSymbolTypeName(string? typeName)
+    internal static TwinCATDataType? MapSymbolTypeName(string? typeName)
     {
         if (typeName is null) return null;
+        // A TwinCAT 2 data-type upload pads some member type names with a trailing blank
+        // ("REAL ", "DINT " on a TC 2.11 CX) — trim before matching.
+        var name = typeName.Trim();
         // SymbolLoader emits STRING(80) / WSTRING(80) with the declared bound baked into
         // the type name — strip the "(...)" suffix so sized strings map onto the bare
-        // String/WString atom the driver speaks.
-        var paren = typeName.IndexOf('(');
-        var bare = paren > 0 ? typeName[..paren] : typeName;
+        // String/WString atom the driver speaks. Only for the string kinds: any other
+        // parenthesised form ("INT (VAR_IN_OUT)" — a 4-byte reference on TC2) is not the
+        // scalar its prefix names and stays unsupported.
+        var paren = name.IndexOf('(');
+        var bare = paren > 0 ? name[..paren] : name;
+        if (paren > 0 && bare is not ("STRING" or "WSTRING")) return null;
         return bare switch
         {
             "BOOL" or "BIT" => TwinCATDataType.Bool,
             "SINT" or "BYTE" => TwinCATDataType.SInt,
-            "USINT" => TwinCATDataType.USInt,
-            "INT" or "WORD" => TwinCATDataType.Int,
-            "UINT" => TwinCATDataType.UInt,
-            "DINT" or "DWORD" => TwinCATDataType.DInt,
-            "UDINT" => TwinCATDataType.UDInt,
+            // TwinCAT 2 reports top-level globals by their ADS base-type name (INT16 / UINT16 / …),
+            // and the Beckhoff type system keeps that spelling as a built-in primitive
+            // (AdsSymbolProvider.CreateBuildInTypes) — map each like its IEC twin.
+            "USINT" or "UINT8" => TwinCATDataType.USInt,
+            "INT" or "WORD" or "INT16" => TwinCATDataType.Int,
+            "UINT" or "UINT16" => TwinCATDataType.UInt,
+            "DINT" or "DWORD" or "INT32" => TwinCATDataType.DInt,
+            "UDINT" or "UINT32" => TwinCATDataType.UDInt,
             "LINT" or "LWORD" => TwinCATDataType.LInt,
             "ULINT" => TwinCATDataType.ULInt,
-            "REAL" => TwinCATDataType.Real,
-            "LREAL" => TwinCATDataType.LReal,
+            "REAL" or "FLOAT" => TwinCATDataType.Real,
+            "LREAL" or "DOUBLE" => TwinCATDataType.LReal,
             "STRING" => TwinCATDataType.String,
             "WSTRING" => TwinCATDataType.WString,
             "TIME" => TwinCATDataType.Time,
diff --git a/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests/TwinCATSymbolTypeNameTests.cs b/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests/TwinCATSymbolTypeNameTests.cs
new file mode 100644
index 00000000..177bc036
--- /dev/null
+++ b/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests/TwinCATSymbolTypeNameTests.cs
@@ -0,0 +1,60 @@
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.Driver.TwinCAT;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.TwinCAT.Tests;
+
+/// <summary>
+///     Pins <c>AdsTwinCATClient.MapSymbolTypeName</c> — the symbol-browse type mapper — against the type
+///     names a real TwinCAT 2 PLC reports. A name the mapper does not know drops the symbol from
+///     discovery silently, so every TC2 spelling below was a symbol the browse never offered.
+/// </summary>
+[Trait("Category", "Unit")]
+public sealed class TwinCATSymbolTypeNameTests
+{
+    /// <summary>
+    ///     TwinCAT 2 reports top-level integer globals by their ADS base-type name, not the IEC name:
+    ///     the Elma cleaner Z33856 (TC 2.11, symbol upload 2026-09-24) lists 233 symbols as
+    ///     <c>INT16</c> and 121 as <c>UINT16</c> (e.g. <c>.ACTUALOPERATIONMODE</c>). The Beckhoff
+    ///     type system carries these as built-in primitives (<c>AdsSymbolProvider.CreateBuildInTypes</c>:
+    ///     INT16, UINT16, INT32, UINT32, UINT8, FLOAT, DOUBLE), so <c>IDataType.Name</c> arrives spelled
+    ///     that way and must map like its IEC twin.
+    /// </summary>
+    /// <param name="typeName">The type name as the PLC / Beckhoff type system reports it.</param>
+    /// <param name="expected">The driver atomic type it must map to.</param>
+    [Theory]
+    [InlineData("INT16", TwinCATDataType.Int)]
+    [InlineData("UINT16", TwinCATDataType.UInt)]
+    [InlineData("INT32", TwinCATDataType.DInt)]
+    [InlineData("UINT32", TwinCATDataType.UDInt)]
+    [InlineData("UINT8", TwinCATDataType.USInt)]
+    [InlineData("FLOAT", TwinCATDataType.Real)]
+    [InlineData("DOUBLE", TwinCATDataType.LReal)]
+    public void TwinCAT2_ads_base_type_names_map_like_their_iec_twins(string typeName, TwinCATDataType expected)
+        => AdsTwinCATClient.MapSymbolTypeName(typeName).ShouldBe(expected);
+
+    /// <summary>
+    ///     The same TC2 data-type upload spells struct members with a trailing blank — <c>"REAL "</c>
+    ///     (54 members on Z33856) and <c>"DINT "</c> (24) — so the name is trimmed before matching.
+    /// </summary>
+    /// <param name="typeName">A padded type name.</param>
+    /// <param name="expected">The driver atomic type it must map to.</param>
+    [Theory]
+    [InlineData("REAL ", TwinCATDataType.Real)]
+    [InlineData("DINT ", TwinCATDataType.DInt)]
+    [InlineData(" STRING(80) ", TwinCATDataType.String)]
+    public void Padded_type_names_are_trimmed(string typeName, TwinCATDataType expected)
+        => AdsTwinCATClient.MapSymbolTypeName(typeName).ShouldBe(expected);
+
+    /// <summary>The IEC spellings, sized strings and unsupported names are unchanged.</summary>
+    [Fact]
+    public void Existing_iec_mappings_are_unchanged()
+    {
+        AdsTwinCATClient.MapSymbolTypeName("INT").ShouldBe(TwinCATDataType.Int);
+        AdsTwinCATClient.MapSymbolTypeName("STRING(8)").ShouldBe(TwinCATDataType.String);
+        AdsTwinCATClient.MapSymbolTypeName("WSTRING(20)").ShouldBe(TwinCATDataType.WString);
+        AdsTwinCATClient.MapSymbolTypeName("ST_LOGDATA").ShouldBeNull();
+        AdsTwinCATClient.MapSymbolTypeName("INT (VAR_IN_OUT)").ShouldBeNull();
+        AdsTwinCATClient.MapSymbolTypeName(null).ShouldBeNull();
+    }
+}