Remove suffix (…) from post excerpt

Hi, I tried to add the following codes to the functions.php in order to remove the “…” behind my post summaries. However both codes do not seem to work.
(Btw: I use summaries as post excerpts, not the first number of characters from the posts).

function trim_excerpt($text) {
  return rtrim($text,'[...]');
}
add_filter('get_the_excerpt', 'trim_excerpt');

Or

function new_excerpt_more( $more ) {
	return '';
}
add_filter('excerpt_more', 'new_excerpt_more');