php ftp problem

I am using the following code to ftp images to the server.  This code works fine for small files but Fails for files that are 1mb or more.

I need to ftp files of 8 and 9MB Is there a setting to allow larger ftp's?


<?

// set up basic connection
$ftp_server = "ftp.mysite.com";
$conn_id = ftp_connect($ftp_server);

// login with username and password
$ftp_user_name = "name";
$ftp_password = "password";
$login_result = ftp_login($conn_id, $ftp_user_name, $ftp_password);


// check connection
if ((!$conn_id) || (!$login_result)) {
       echo "FTP connection has failed!\n";
       echo "Attempted to connect to $ftp_server for user $ftp_user_name";
       exit;
   } else {
       echo "Connected to $ftp_server, for user $ftp_user_name";
   }
 
// upload the file  

$destination_file = './new.pdf';
$source_file = $_FILES['imagefile']['tmp_name'];
$upload = ftp_put($conn_id, $destination_file, $source_file, FTP_ASCII);

// check upload status
if (!$upload) {
       echo "FTP upload has failed!";
   } else {
       echo "Uploaded $source_file to $ftp_server as $destination_file";
   }
   
// close the FTP stream
ftp_close($conn_id);
?>