diff --git a/src/Mod/Fem/femobjects/constraint_electrostaticpotential.py b/src/Mod/Fem/femobjects/constraint_electrostaticpotential.py
index caa7fe9402..358a621711 100644
--- a/src/Mod/Fem/femobjects/constraint_electrostaticpotential.py
+++ b/src/Mod/Fem/femobjects/constraint_electrostaticpotential.py
@@ -39,45 +39,71 @@ class ConstraintElectrostaticPotential(base_fempythonobject.BaseFemPythonObject)
 
     def __init__(self, obj):
         super(ConstraintElectrostaticPotential, self).__init__(obj)
-        obj.addProperty(
-            "App::PropertyFloat",
-            "Potential",
-            "Parameter",
-            "Potential"
-        ),
-        obj.addProperty(
-            "App::PropertyBool",
-            "PotentialEnabled",
-            "Parameter",
-            "Potential Enabled"
-        ),
-        obj.addProperty(
-            "App::PropertyBool",
-            "PotentialConstant",
-            "Parameter",
-            "Potential Constant"
-        ),
-        obj.addProperty(
-            "App::PropertyBool",
-            "ElectricInfinity",
-            "Parameter",
-            "Electric Infinity"
-        ),
-        obj.addProperty(
-            "App::PropertyBool",
-            "ElectricForcecalculation",
-            "Parameter",
-            "Electric Force Calculation"
-        ),
-        obj.addProperty(
-            "App::PropertyInteger",
-            "CapacitanceBody",
-            "Parameter",
-            "Capacitance Body"
-        ),
-        obj.addProperty(
-            "App::PropertyBool",
-            "CapacitanceBodyEnabled",
-            "Parameter",
-            "Capacitance Body Enabled"
-        )
+        self.add_properties(obj)
+
+    def onDocumentRestored(self, obj):
+        self.add_properties(obj)
+
+    def add_properties(self, obj):
+        if not hasattr(obj, "Potential"):
+            obj.addProperty(
+                "App::PropertyFloat",
+                "Potential",
+                "Parameter",
+                "Potential"
+            ),
+            obj.Potential = 0.0
+
+        if not hasattr(obj, "PotentialEnabled"):
+            obj.addProperty(
+                "App::PropertyBool",
+                "PotentialEnabled",
+                "Parameter",
+                "Potential Enabled"
+            ),
+            obj.PotentialEnabled = False
+
+        if not hasattr(obj, "PotentialConstant"):
+            obj.addProperty(
+                "App::PropertyBool",
+                "PotentialConstant",
+                "Parameter",
+                "Potential Constant"
+            ),
+            obj.PotentialConstant = False
+
+        if not hasattr(obj, "ElectricInfinity"):
+            obj.addProperty(
+                "App::PropertyBool",
+                "ElectricInfinity",
+                "Parameter",
+                "Electric Infinity"
+            ),
+            obj.ElectricInfinity = False
+
+        if not hasattr(obj, "ElectricForcecalculation"):
+            obj.addProperty(
+                "App::PropertyBool",
+                "ElectricForcecalculation",
+                "Parameter",
+                "Electric Force Calculation"
+            ),
+            obj.ElectricForcecalculation = False
+
+        if not hasattr(obj, "CapacitanceBody"):
+            obj.addProperty(
+                "App::PropertyInteger",
+                "CapacitanceBody",
+                "Parameter",
+                "Capacitance Body"
+            ),
+            obj.CapacitanceBody = 0
+
+        if not hasattr(obj, "CapacitanceBodyEnabled"):
+            obj.addProperty(
+                "App::PropertyBool",
+                "CapacitanceBodyEnabled",
+                "Parameter",
+                "Capacitance Body Enabled"
+            )
+            obj.CapacitanceBodyEnabled = False