Команда require_once dirname(__file__) ??

скачал библиотеку aldas/modbus-tcp-client

установил при помощи    composer require aldas/modbus-tcp-client

на команду 8 require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';

выдает 

Warning: require_once(C:\xampp\htdocs\owen/../Phpmodbus/ModbusMaster.php): Failed to open stream: No such file or directory in C:\xampp\htdocs\owen\index.php on line 8

Fatal error: Uncaught Error: Failed opening required 'C:\xampp\htdocs\owen/../Phpmodbus/ModbusMaster.php' (include_path='C:\xampp\php\PEAR') in C:\xampp\htdocs\owen\index.php:8 Stack trace: #0 {main} thrown in C:\xampp\htdocs\owen\index.php on line 8

echo " Изучаем Modbus протокол   htp";

// Autoloading via Composer
require __DIR__ . '/vendor/autoload.php';
 
require_once dirname(__FILE__) . '/../Phpmodbus/ModbusMaster.php';

// Create Modbus object
$modbus = new ModbusMaster("192.168.100.15", "TCP");

в чем причина?