Siemens sirius 3rf2 solid state contactors siemens 3rf2310 1aa02 this 105a 24 to 230v ac solid state contactor is from the sirius 3rf23 range features a high power thyristor with high reverse voltage the space saving design features integrated heatsinks and the unit is touch safe without accessories siemens 3rf2310 1aa02 sirius semiconductor contactor 24 230 vac 105a