Problems with Cron settings in Automation

I'm trying this Cron settings:
30 22 * * Sat,Sun
/*
Control HORARIO
BAJAR persiana FIN de SEMANA
*/
public void Run()
{
DriverHelper.ProcessCommad(Domains.MYSENSORS, "N21S0", "ControlDown", "");
System.Threading.Thread.Sleep(35000);
DriverHelper.ProcessCommad(Domains.MYSENSORS, "N21S0", "ControlStop", "");
}

This case is only for Weekends.

In weekdays Works sometimes but I never know when:
15 22 * * Mon-Fri