public static function readTime5($time) {
		if (empty($time) || $time=='NULL') return null;
		if (is_numeric($time)) {
			return '00:' . $time;
		} else {
			$temp = explode(':', $time);
			return str_pad(intval($temp[0]), 2, '0', STR_PAD_LEFT) . ':' .str_pad(intval($temp[1]), 2, '0', STR_PAD_LEFT);
		}
	}