diff --git a/components/rx/trunk/rxdbdateedit.pas b/components/rx/trunk/rxdbdateedit.pas
index bd3a99d21..a8fee0607 100644
--- a/components/rx/trunk/rxdbdateedit.pas
+++ b/components/rx/trunk/rxdbdateedit.pas
@@ -372,7 +372,7 @@ end;
 
 procedure TRxDBCalcEdit.UpdateData(Sender: TObject);
 begin
-  if Assigned(FDataLink.Field) then
+  if Assigned(FDataLink.Field) and FDataLink.Edit then
   begin
     if Self.Text<>'' then
       FDataLink.Field.AsFloat := Self.AsFloat