Siemens 3RT29261CD00 SIRIUS Surge Suppressor. SIRIUS Surge Suppressor, For Use With: Size S0 Motor Contactor, 127 to 240 VAC/150 to 250 VDC, 50/60 Hz, -25 to 60 deg C Operating Temperature, Clip-On Mount, 19 mm H x 30 mm W x 12 mm D. Additional Description: SIEM-3RT2926-1CD00 SURGE SUPPR S0 RC AC 127-240, DC 150-250. Catalog Description: 3RT2926-1cd00 3rt-AC 127...240V, DC 150...250V, for motorcontactor size s0.