3UF7121-1AA01-0 SIRIUS Measuring Module, 110-690V AC, 400A I

The Siemens SIRIUS 3UF7121-1AA01-0 is a current/voltage measuring module rated for 110 to 690 V AC at 50/60 Hz, covering common line voltages in industrial panels. It provides overload protection with trip class CLASS 5E and can handle inrush currents up to 400 A (10 x Io) for motor starting. Energy measurement accuracy is ±5% from 2.25 A to 80 A, and ±10% from 80 A to 320 A under standard line conditions (0.85 x 110 V to 1.1 x 690 V, cos φ 0.5–1, 25 °C). Mounting is screw or snap-on in any position; the module envelope is 84 x 45 x 64 mm (H x W x D) with 30 mm clearance above and below, zero on the sides. Active in production with IECEx (PTB 18.0004X) and UKCA approvals. Sourcing is straightforward — this part is available to order against an RFQ.