PE pick-up for SIRIUS motor starters — 63 A, 15 mm wide
The Siemens 3RA6870-4AB is a protective earth (PE) pick-up module in the SIRIUS motor starter family, rated for 63 A operational current at 400 V AC. It provides a dedicated PE tap connection for the main circuit, allowing the protective earth conductor to be wired directly to the motor starter assembly rather than looped through a separate terminal block. At 15 mm wide, this module occupies one single-width slot on the DIN rail, matching the footprint of the SIRIUS 3RA2 contactor assemblies it pairs with. The plug-in fixing means it snaps onto the rail without tools and locks in place — no mounting screws needed.
In a motor starter circuit, this matches the full-load current of motors up to roughly 30 kW at 400 V (assuming typical power factor and efficiency). The screw-type terminals accept conductors from 16 mm² down to 10 mm² for the load-side outgoing feeder, with a stripped length of 10 mm and tightening torque of 2 to 2.5 N·m. Pollution degree 3 means the module is rated for industrial environments where conductive dust or occasional condensation may occur — typical for motor control centers (MCCs) and panel shops. The operating temperature range of -20 to +60 °C covers most indoor industrial installations without derating, though the 2000 m maximum altitude should be noted for high-elevation sites.
Active production — sourcing this part
For panel builders and MRO buyers: this PE pick-up is a standard line item in the SIRIUS 3RA2/3RA6 system, so lead times typically align with the broader SIRIUS portfolio. No official successor or cross-reference exists — it is the current production part for this function.
Environmental and mechanical qualification
The module is qualified for shock resistance to semi-sinusoidal 6 m/s² at 10 ms and vibration resistance per the profile: 4 to 5.8 Hz at 15 mm displacement, then 5.8 to 500 Hz at 2 m/s² acceleration, 10 cycles. This covers machine-mounted applications such as conveyors, pumps, and compressors where the starter sees mechanical stress from the driven equipment. Storage and transport temperature range is -55 to +80 °C, which is standard for SIRIUS components and allows for unheated warehouse storage or container shipping. The functional designation per EN 61346-2 and IEC 81346-2 is 'X', indicating a protective earth component in the equipment identification scheme.