SIRIUS S0 power contactor — 3RT1026-3AL16
The Siemens 3RT1026-3AL16 is a SIRIUS S0-frame power contactor rated for 11 kW at 400 V in AC-2 duty, meaning it handles moderate overloads typical of slip-ring motor starting or mixed resistive-inductive loads. The 24 VDC coil pulls in reliably across the 0.8 to 1.1 x Us tolerance band at 60 Hz. Three normally-open main contacts switch the power circuit; two auxiliary contacts (one NO, one NC) are integrated for feedback or interlocking. The S0 frame footprint — 65 mm wide, 85 mm tall, 91 mm deep — fits alongside other SIRIUS S0 components on the same rail without extra spacing, and side-by-side mounting is explicitly permitted.
At AC-2 at 400 V the contactor is rated 11 kW; the AC-4 rating at 400 V is 15.5 A, which governs plugging and inching duty where the contactor makes and breaks motor current at full stall. The AC-12 rating of 10 A covers resistive loads in control circuits. For motor starting (AC-3), the 11 kW figure at 400 V is the practical selection point — pair it with a 35 A gL/gG fuse for Type 2 coordination, or a 100 A fuse for Type 1. The coil draws 10 A at 24 V rated value, with a pickup/dropout range of 0.8 to 1.1 x Us at 60 Hz.
Main current circuit uses screw-type terminals accepting 2x (0.25 to 2.5 mm²) solid, 2x (1 to 2.5 mm²) stranded, or up to 2x 10 mm² single-core. AWG equivalents are 2x (16 to 12) solid and 2x (14 to 10) stranded, with a maximum 1x 8 AWG. The auxiliary contact terminals accept 2x (0.25 to 2.5 mm²) solid.