Siemens 3RT7025-1AH20 — SIRIUS S0 Contactor
The Siemens 3RT7025-1AH20 is a 3-pole SIRIUS S0 contactor rated for AC-3 switching up to 690 V.
AC-3 rated operational voltage maxes at 690 V, covering 400 V and 480 V motor circuits common in European and North American panels. Rated operational current at 400 V is 3 A in AC-3 duty — sized for smaller motor loads (typically 0.75–1.5 kW range depending on the motor's rated current). The 6 A rating at 230 V AC-3 gives headroom for 230 V three-phase motors in that same power band. Switching frequency limits: 800 operations per hour at AC-3, 250 per hour at AC-4. Coil consumption is 0.72 W closing, 0.24 W holding at DC. The holding power is the steady-state draw once the contactor picks. IP20 on the front and terminals means finger-safe but not washdown-rated — suitable for enclosed panels, not open outdoor or wet-area mounting.
Screw terminals on both main and auxiliary/control circuits accept 2x 0.5–2.5 mm² solid or stranded, or 2x 0.5–1.5 mm² finely stranded with ferrule.