diff --git a/src/easyscience/Objects/new_variable/descriptor_number.py b/src/easyscience/Objects/new_variable/descriptor_number.py
index 95c6fc5e..4fd25709 100644
--- a/src/easyscience/Objects/new_variable/descriptor_number.py
+++ b/src/easyscience/Objects/new_variable/descriptor_number.py
@@ -101,7 +101,7 @@ def full_value(self) -> Variable:
 
     @full_value.setter
     def full_value(self, full_value: Variable) -> None:
-        raise AttributeError(f'Full_value is read-only. Change the value and variance seperately. Or create a new {self.__class__.__name__}.')  # noqa: E501
+        raise AttributeError(f'Full_value is read-only. Change the value and variance seperately. or create a new {self.__class__.__name__}.')  # noqa: E501
     
     @property
     def value(self) -> numbers.Number:
@@ -122,7 +122,7 @@ def value(self, value: numbers.Number) -> None:
         """
         if not isinstance(value, numbers.Number) or isinstance(value, bool):
             raise TypeError(f'{value=} must be a number')
-        self._scalar.value = float(value)
+        self._scalar.value = value
 
     @property
     def unit(self) -> str:
diff --git a/src/easyscience/Objects/new_variable/parameter.py b/src/easyscience/Objects/new_variable/parameter.py
index 56dad214..b48f6a91 100644
--- a/src/easyscience/Objects/new_variable/parameter.py
+++ b/src/easyscience/Objects/new_variable/parameter.py
@@ -147,8 +147,24 @@ def full_value(self) -> Variable:
         return self._scalar
 
     @full_value.setter
+    @property_stack_deco
     def full_value(self, scalar: Variable) -> None:
-        raise AttributeError(f'Full_value is read-only. Change the value and variance seperately. Or create a new {self.__class__.__name__}.')  # noqa: E501
+        """
+        Set the value of self. This creates a scipp scalar with a unit.
+
+        :param full_value: New value of self
+        """
+        if not self.enabled:
+            if global_object.debug:
+                raise CoreSetException(f'{str(self)} is not enabled.')
+            return
+        if not isinstance(scalar, Variable) and len(scalar.dims) == 0:
+            raise TypeError(f'{scalar=} must be a Scipp scalar')
+        if not isinstance(scalar.value, numbers.Number) or isinstance(scalar.value, bool):
+            raise TypeError('value of Scipp scalar must be a number')
+        self._scalar = scalar
+        if self._callback.fset is not None:
+            self._callback.fset(scalar)
 
     @property
     def value(self) -> numbers.Number:
@@ -199,7 +215,7 @@ def value(self, value: numbers.Number) -> None:
 
         value = self._constraint_runner(self._constraints.virtual, value)
 
-        self._scalar.value = float(value)
+        self._scalar.value = value
         if self._callback.fset is not None:
             self._callback.fset(self._scalar.value)
 
diff --git a/tests/unit_tests/Objects/new_variable/test_parameter.py b/tests/unit_tests/Objects/new_variable/test_parameter.py
index 5269d81b..017e76bd 100644
--- a/tests/unit_tests/Objects/new_variable/test_parameter.py
+++ b/tests/unit_tests/Objects/new_variable/test_parameter.py
@@ -292,9 +292,15 @@ def test_full_value_no_match_callback(self, parameter: Parameter):
         assert parameter._callback.fget.call_count == 1
 
     def test_set_full_value(self, parameter: Parameter):
-        # When Then Expect
-        with pytest.raises(AttributeError):
-            parameter.full_value = sc.scalar(2, unit='s')
+        # When
+        self.mock_callback.fget.return_value = sc.scalar(1, unit='m')
+
+        # Then
+        parameter.full_value = sc.scalar(2, unit='m')
+
+        # Expect
+        parameter._callback.fset.assert_called_once_with(sc.scalar(2, unit='m')) 
+        assert parameter._scalar == sc.scalar(2, unit='m')
     
     def test_copy(self, parameter: Parameter):
         # When Then