SIRIUS Power Contactor, S0 Frame – 3RT2026-1BB44-ZX95
The Siemens 3RT2026-1BB44-ZX95 is a SIRIUS power contactor in the S0 frame size, designed for switching motor and resistive loads in industrial control panels. It mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715, with a mounting position flexibility of ±180° rotation on a vertical surface and ±22.5° tilt forward/backward. The coil is rated 24 VDC with a pickup ratio of 0.8 x rated value and a dropout ratio of 1.1 x rated value, meaning it reliably pulls in at 19.2 V and drops out at 26.4 V. Main contacts are rated 16 A (AC-3) and 8 A (AC-1), with a mechanical life of 10 million operations typical. Switching frequency varies by duty: up to 1000 cycles/hour at AC-1, 750 at AC-2 and AC-3, 250 at AC-4. For motor starting (AC-3e), it's rated 750 cycles/hour. The contactor handles motor loads up to 3 hp at 230 V and 3 A at 400 V.
Ratings and What They Mean for Fit
The S0 frame size (45 mm wide, 85 mm tall, 151 mm deep) is a standard footprint for 16 A contactors in Siemens' SIRIUS line — it fits existing panel layouts designed for this frame. The 16 A AC-3 rating governs motor switching; the 8 A AC-1 rating covers resistive loads like heaters. For auxiliary contacts, the 24 VDC rating is 6 A, derating to 0.3 A at 220 VDC — important for DC control circuits. Wire capacity accepts solid or stranded conductors from 1 to 10 mm², with dual-wire capability for 2x (0.5–1.5 mm²) or 2x (0.75–2.5 mm²). Clearance distances: 10 mm upwards, downwards, and forwards; 6 mm at the sides. Operating temperature range is -25 to +60 °C, storage -55 to +80 °C. Arcing time is 10–18 ms at DC, 10 ms at AC. The screw-type terminals are standard for panel wiring — no special tooling needed.