diff --git a/InvenTree/InvenTree/conversion.py b/InvenTree/InvenTree/conversion.py
index 8637ae382b..67e18dc0e7 100644
--- a/InvenTree/InvenTree/conversion.py
+++ b/InvenTree/InvenTree/conversion.py
@@ -91,7 +91,7 @@ def convert_physical_value(value: str, unit: str = None):
         # At this point we *should* have a valid pint value
         # To double check, look at the maginitude
         float(val.magnitude)
-    except (TypeError, ValueError):
+    except (TypeError, ValueError, AttributeError):
         error = _('Provided value is not a valid number')
     except (pint.errors.UndefinedUnitError, pint.errors.DefinitionSyntaxError):
         error = _('Provided value has an invalid unit')
diff --git a/InvenTree/InvenTree/tests.py b/InvenTree/InvenTree/tests.py
index 83c340e7e5..a68f7c4739 100644
--- a/InvenTree/InvenTree/tests.py
+++ b/InvenTree/InvenTree/tests.py
@@ -56,6 +56,23 @@ class ConversionTest(TestCase):
             q = InvenTree.conversion.convert_physical_value(val).to_base_units()
             self.assertEqual(q.magnitude, expected)
 
+    def test_invalid_values(self):
+        """Test conversion of invalid inputs"""
+
+        inputs = [
+            '-',
+            ';;',
+            '-x',
+            '?',
+            '--',
+            '+',
+            '++',
+        ]
+
+        for val in inputs:
+            with self.assertRaises(ValidationError):
+                InvenTree.conversion.convert_physical_value(val)
+
 
 class ValidatorTest(TestCase):
     """Simple tests for custom field validators."""
diff --git a/InvenTree/templates/js/translated/part.js b/InvenTree/templates/js/translated/part.js
index ebce845a7c..bba41ab980 100644
--- a/InvenTree/templates/js/translated/part.js
+++ b/InvenTree/templates/js/translated/part.js
@@ -1404,6 +1404,7 @@ function createPartParameter(part_id, options={}) {
 function editPartParameter(param_id, options={}) {
     options.fields = partParameterFields();
     options.title = '{% trans "Edit Parameter" %}';
+    options.focus = 'data';
 
     options.processBeforeUpload = function(data) {
         // Convert data to string