diff --git a/app/Filament/Resources/MotorTestingMasterResource.php b/app/Filament/Resources/MotorTestingMasterResource.php
index f6759bfce..8772b08ed 100644
--- a/app/Filament/Resources/MotorTestingMasterResource.php
+++ b/app/Filament/Resources/MotorTestingMasterResource.php
@@ -108,6 +108,12 @@ class MotorTestingMasterResource extends Resource
                                 }
                             })
                     ->selectablePlaceholder(false)
+                    ->afterStateUpdated(function ($state, callable $set, callable $get) {
+
+                        if ($state == 'Single' && $get('connection') == 'Star-Delta') {
+                            $set('phase', 'Three');
+                        }
+                    })
                     ->default('Single')
                     ->required()
                     ->reactive(),
@@ -151,6 +157,11 @@ class MotorTestingMasterResource extends Resource
                                 ->toArray();
                         }
                     })
+                    ->afterStateUpdated(function ($state, callable $set) {
+                        if ($state == 'Star-Delta') {
+                            $set('phase', 'Three');
+                        }
+                    })
                     ->required()
                     ->default('Star')
                     ->reactive(),