Spring execute method every 15 minutes

I tried to use cron expression from this site http://ift.tt/19UHFqs

@Scheduled(cron = "0 0/15 * 1/1 * ? *")
    public void clearRps() {

    }

But it throws by: java.lang.IllegalStateException: Encountered invalid @Scheduled method 'clearRps': Cron expression must consist of 6 fields (found 7 in "0 0/15 * 1/1 * ? *")