16 A AC-3 reversing starter — what the rating means for your motor circuit
The 3RA2220-4AB26-0AP0: This is a SIRIUS reversing starter, meaning it combines two contactors and an overload relay in one package to reverse a three-phase motor without external interlocking wiring. The AC-3 rating of 16 A at 400 V covers typical squirrel-cage motors up to about 7.5 kW — that's the current during starting and plugging, not just running load.
Panel fit — S0 size and DIN rail mounting
The S0 feeder size and dimensions — 120 mm deep, 90 mm wide, 265 mm tall — tell you it fits the standard S0 footprint. Mounting is on a 35 mm DIN rail via an adapter, with screw-mount option if the panel lacks a rail. Clearance needs: 50 mm above, 32 mm in front, 10 mm below, 10 mm at the sides. That front clearance is tight — make sure the enclosure door or gland plate doesn't crowd the terminals. The supplied contactor is 3RT2026-1AP00 and the link module is 3RA2921-1AA00 — both are standard SIRIUS S0 parts, so spares and replacements are straightforward to source.
The operating temperature range of -20 to +60 °C covers most indoor panel environments; storage from -50 to +80 °C is typical for warehouse conditions.