SIRIUS S0 power contactor — 27 A at 480 V
The Siemens 3RT2027-2AP04-ZX95 is a SIRIUS-branded power contactor in the S0 frame size, rated for 27 A at 480 V AC-3 duty — the motor-switching rating that governs real load handling on a 480 V line. Spring-type terminals on the coil save the panel builder a screwdriver step on the control wiring, though the main contact terminals accept solid or stranded 1 to 10 mm². Mounting is screw or snap-on onto 35 mm DIN rail per EN 60715, with ±180° rotation and ±22.5° tilt allowed on a vertical surface.
DIN-rail fit and clearances
The S0 frame occupies 45 mm width, 102 mm height, and 144 mm depth. Minimum clearances: 10 mm upwards, downwards, and forwards; 6 mm at the side. That side clearance is tighter than some panel builders expect — adjacent devices or wire duct need that 6 mm, not zero.
Switching frequency and contact ratings
Maximum switching rates: 1,000 cycles/hour at AC-1 (resistive), 750 cycles/hour at AC-2, AC-3, and AC-3e, and 250 cycles/hour at AC-4 (–,). The AC-4 limit reflects the heavier arc duty of plugging or inching. Auxiliary contact block is not fitted as standard; the main contact rating is 18 to 8 A. Arcing time is 10 ms.