The Siemens 3RT7027-1AQ05 is a size S0 3-pole contactor rated for AC-3 and AC-3e duty up to 690 V maximum. The auxiliary contact ratings are load-specific: 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V. That means the same auxiliary set can handle a 230 V control relay coil or a 690 V signal contact, but the current drops with voltage — size your control load to the applicable row. Contact reliability is specified for PLC-level signals (17 V, 5 mA), so this contactor can directly drive a 24 VDC PLC input without a separate interface relay — no exceptions. The coil closing power is 0.82 W DC and holding power 0.24 W DC. That low holding draw means the control transformer or DC supply can be sized for the inrush, not the continuous load — a common gotcha when a panel has multiple contactors.
IP20 on the front and terminals means finger-safe against accidental contact, but it is not sealed — keep it inside a panel rated for the environment. Wire sizes: solid or stranded 2×(0.5 to 1.5 mm²) and 2×(0.75 to 2.5 mm²), same range for finely stranded with ferrule.
The 3RT7027-1AQ05 is available to order against an RFQ.