diff -r d968d586ad16 -r 9622418ac28c dialogs/LDPowerRailDialog.py
--- a/dialogs/LDPowerRailDialog.py	Thu Mar 28 13:39:58 2019 +0100
+++ b/dialogs/LDPowerRailDialog.py	Thu Mar 28 14:06:53 2019 +0100
@@ -155,7 +155,7 @@
         self.RefreshPreview()
         event.Skip()
 
-    def RefreshPreview(self):
+    def DrawPreview(self):
         """
         Refresh preview panel of graphic element
         Override BlockPreviewDialog function
@@ -166,5 +166,4 @@
                                     self.GetPowerRailType(),
                                     connectors=self.PinNumber.GetValue())
 
-        # Call BlockPreviewDialog function
-        BlockPreviewDialog.RefreshPreview(self)
+        return BlockPreviewDialog.DrawPreview(self)