Siemens 3RT7027-1AV05 — S0 Contactor, Active, AC-3 Rated
The Siemens 3RT7027-1AV05 is a current-production SIRIUS S0 contactor, 3-pole with 3 normally-open main contacts, controlled by an AC coil. It's rated for AC-3 switching duty up to 690 V, with a maximum operating current of 6 A at 230 V and 3 A at 400 V. The screw-type terminals on both main and auxiliary circuits accept 2x (0.5…1.5 mm²) or 2x (0.75…2.5 mm²) solid/stranded wire. Front and terminal protection is IP20, so it's suited for enclosed panel mounting — not washdown environments.
Mounting and Integration
Mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022. The S0 frame footprint is 55 mm wide, 85.5 mm tall, 91 mm deep. Side-by-side mounting is permitted, and the mounting position allows ±180° rotation on a vertical surface, plus ±22.5° tilt forward/backward. Pollution degree 3 rated — suitable for industrial enclosures where conductive dust or humidity is present.
Ratings and Performance
Rated insulation voltage 690 V, surge voltage resistance 6 kV. At AC-3 duty, maximum switching rate is 800 operations per hour; at AC-4, 250 ops/hr. The DC-13 rating at 220 V is 0.3 A — relevant for switching DC solenoids or brake coils in the same panel. Coil holding power is 0.24 W DC; closing power 0.82 W DC. Auxiliary contacts are rated for PLC-level signals (17 V, 5 mA) — reliable for direct input to a controller without interposing relays.
Coordination and Protection
For type 2 coordination ('no damage to the contactor on short circuit'), the required upstream fuse is gL/gG NH 3NA: 50 A. For type 1 coordination (contactor may need replacement after fault), the same fuse type rated 125 A is specified. Operating temperature range is -10 to +55 °C; storage from -25 to +70 °C. Shock resistance: 12.5g at 5 ms, 7.8g at 10 ms sine pulse.