The Siemens 3RT1316-2AV00 is a SIRIUS S00 power contactor with four normally-open main contacts, spring-loaded terminals for the main current circuit, and a rated operational voltage of 400 V at 50/60 Hz. It delivers 4 kW at 400 V in AC-2 duty, which covers slip-ring motor starting and plugging applications — the AC-2 rating is the one that governs real motor-switching life here, not the higher AC-3 figure a smaller-frame contactor might carry.
Spring-loaded terminals accept 2x (0.25 to 2.5 mm²) solid or stranded, or 2x (24 to 14 AWG). For Type 1 coordination, the required backup fuse is gL/gG 35 A; for Type 2 coordination, it's gL/gG 20 A.
