What this contactor is and what it does
The Siemens SIRIUS 3RT2026-1FB48-0ME1-ZX95 is a size S0 power contactor rated for switching motor loads up to 21 A in AC-3 duty at 480 V — that is the current-carrying capacity for starting and running a three-phase induction motor under full load, not just resistive heating. The 24 VDC coil pulls 6 A inrush and holds at the same nominal voltage, so your control transformer or DC supply needs to deliver that peak without droop. Mechanical endurance is 10 million operations typical, which for a conveyor or pump cycling a few times an hour translates to years of service before the contacts wear.
Mounting and integration into the panel
Mounts via screw or snap-on onto a 35 mm standard mounting rail per DIN EN 60715. The S0 frame footprint is 45 mm wide, 85 mm tall, and 151 mm deep — a compact block that fits standard sub-distribution boards and motor control centers. The mounting position is flexible: +/-180° rotation on a vertical surface, and can be tilted forward/backward by +/-22.5° on a vertical surface, which helps when laying out a dense panel with cable ducts and busbars. Terminals accept solid or stranded copper from 1 to 10 mm². The main contact screw torque range is 16 to 8 Nm. Clearance distances: 10 mm upwards, forwards, and downwards, 6 mm at the side.
Duty ratings and switching frequency
Switching frequency depends on the load category. For AC-1 (resistive loads) it can cycle up to 1 000 operations per hour. For AC-2 and AC-3 (slip-ring and squirrel-cage motors) the limit is 750 operations per hour. For AC-4 (plugging / inching) it drops to 250 operations per hour — the arcing time of 10 to 10 ms and DC break time of 15 to 17.5 ms tell you the contactor is designed for moderate switching speeds, not high-cycle servo applications. No auxiliary switch is included on this variant — if your circuit needs a mirror contact or a status feedback to a PLC, you will need to order a separate auxiliary switch block that clips onto the S0 frame.