The Siemens 3RT1026-1AG60 is a SIRIUS S0-frame power contactor with screw-type terminals on the main circuit, rated for motor switching at 11 kW in AC-2 duty at 400 V and 15.5 A in AC-4 duty at 400 V. It also handles 11 kW at 690 V, so it covers 400 V and 690 V motor loads without a frame size bump. It mounts on a 35 mm DIN rail per EN 50022, with a 45 mm width and 85 mm height — a standard S0 footprint that fits alongside other SIRIUS components in a control panel. Side-by-side mounting is allowed, with a 6 mm clearance required at the side. The front face carries an IP20 rating (finger-safe), while the terminal area is IP00 — expect exposed live parts at the wiring points inside an enclosure. Pollution degree 3 means it's rated for industrial environments with conductive contamination.
Motor ratings and coordination
The AC-2 rating (11 kW at 400 V) covers slip-ring motor starting and reversing; the AC-4 rating (15.5 A at 400 V) covers plugging and inching duty where the contactor makes and breaks stalled-rotor current. For general squirrel-cage motor starting (AC-3), the 690 V rating at 11 kW gives a sense of the thermal capacity — the contactor is sized for motors up to that power class. Short-circuit coordination: with type 2 coordination (limited damage), use a gL/gG fuse rated 35 A. With type 1 coordination (replace contactor after fault), a 100 A gL/gG fuse is allowed. These figures govern the upstream protection selection for the motor branch circuit. Auxiliary contacts are rated for switching at various control voltages: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 0.3 A at 220 V DC. The DC switching capacity drops sharply with voltage — the 220 V DC rating at 0.3 A is typical for a contactor of this size.
Termination and wiring
Main circuit screw terminals accept solid/stranded conductors: 2x (1... 2.5 mm²), 2x (2.5... 6 mm²), or a single 10 mm². Auxiliary terminals take 2x (0.5... 1.5 mm²) or 2x (0.75... 2.5 mm²), max 2x 4 mm². AWG equivalents are 2x (16... 12) and 2x (14... 10) for main, with a single 8 AWG maximum. Coil operating range: 0.8... 1.1 × rated voltage at 50 Hz, 0.85... 1.1 at 60 Hz. The coil is rated for both 50 Hz and 60 Hz supply, with a nominal voltage of 100 V at 50 Hz and 100... 110 V at 60 Hz.
Lifecycle and sourcing
For a BOM freeze or critical spare, this part is a fast mover — the S0 frame is one of the most common contactor sizes in European panel builds. Keep one on the shelf if your line runs 11 kW motors at 400 V.