Mage :: getModel（） - > getCollection（）不返回产品

Question

I'm trying to retreive the products from one certain shop in magento. The thing is that the script seems only to work when there are no other shops.

error_reporting(E_ALL);
ini_set('display_errors', '1');
chdir ( dirname ( __FILE__ ) );
$my_folder = dirname ( realpath ( __FILE__ ) );
date_default_timezone_set ( 'Europe/Amsterdam' );
define('MAGENTO_ROOT', $my_folder);
$mageFilename = MAGENTO_ROOT . '/app/Mage.php';
require_once($mageFilename);
$app = Mage::app();
Mage::app()->setCurrentStore(1);
$url = Mage::getBaseUrl(Mage_Core_Model_Store::URL_TYPE_WEB);

function getMainWithVariantsProducts(){

    $productModel = Mage::getModel('catalog/product')->getCollection()
    ->addAttributeToSelect('*')
    ->addAttributeToFilter('type_id', array('eq' => 'configurable'))
    ->setPageSize(100000);

    $main = array();
    $variants = array();

    foreach ($productModel as $_product) {
        echo "<pre>";
        print_r($_product);
        echo "</pre>";
    }
}


mainProduct();

So When I try with it a Magento server with 1 shop it works, ben when I try it with another Magento server it doesn't work.