Se quita el valor 'identificador' del listado y se dejan PSN y SN.

src/FTTHBundle/Admin/ONUAdmin.php

@@ -70,10 +70,10 @@ class ONUAdmin extends WorkflowBaseAdmin
                 'template' => 'FTTHBundle:ONU:base_list_field_client.html.twig'
             ))
             ->add('ip')
-            ->add('serialNumber', 'string', array(
+            ->add('ponSerialNumberAux', 'string', array(
                 'template' => 'FTTHBundle:ONU:base_list_field_upper.html.twig'
             ))
-            ->add('ponSerialNumber', 'string', array(
+            ->add('serialNumber', 'string', array(
                 'template' => 'FTTHBundle:ONU:base_list_field_upper.html.twig'
             ))
             ;