What it is and where it fits
The Siemens 3RT6028-1AK60 is a SIRIUS power contactor in the S0 frame size, designed for switching motor loads and resistive loads in control panels. It mounts on a 35 mm DIN rail per DIN EN 50022 using screw or snap-on fastening, with a width of 45 mm and a depth of 97 mm — a standard footprint that fits most panel layouts without crowding adjacent devices.
Key ratings — what they mean for your BOM
The headline motor-switching rating is 21 A in AC-3e duty at 690 V — that's the current it can make and break for standard squirrel-cage motors under normal starting conditions. AC-3e is the energy-efficient motor variant of AC-3; the same contactor also carries an AC-3 rating at 690 V, so it covers both standard and high-efficiency motor types. The maximum operational voltage across the main poles is 690 V, which covers 400 V and 480 V systems with headroom. For resistive (AC-1) loads, the contactor can switch up to 1 000 operations per hour; for motor starting (AC-3) the maximum is 750 operations per hour. The mechanical life is rated at 10 000 000 switching cycles typical, so this is a long-service part for frequent-start applications like conveyors or pumps. The coil draws 0.28 A at both 50 Hz and 60 Hz — a single coil covers both line frequencies. The contactor is rated for an ambient operating range of -25 °C to +60 °C, with storage from -55 °C to +80 °C. Pollution degree 3 means it's suitable for industrial environments with conductive pollution.
Mounting and wiring details
Main power circuit connections are screw-type terminals, accepting 2 x (0.5 to 1.5 mm²) solid or stranded, or 2 x (0.75 to 2.5 mm²). The minimum permissible conductor cross-section at both 40 °C and 60 °C is 10 mm² — that's the smallest wire size allowed for the main circuit, not the terminal range. The contactor can be mounted side-by-side with zero spacing, which saves rail space in dense panels. Mounting position allows ±180° rotation on a vertical surface, and can be tilted forward/backward by ±22.5°.
Sourcing posture
This is a stocked line item in the SIRIUS contactor family. Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing confirmed at quote time.