What it is and what it does
The Siemens 3RN1013-2BB00 is a thermistor motor protection evaluation unit from the SIRIUS family. It monitors PTC thermistor sensors embedded in motor windings and trips the control circuit when the winding temperature exceeds the sensor's rated response threshold — preventing a burn-out before the overload relay alone would act. The unit accepts a 24 V control supply regardless of whether the panel runs AC or DC — the Type Of Voltage is AC/DC, with rated values of 24 V at 50 Hz, 60 Hz, and DC. That simplifies stocking for mixed-supply sites. It provides two changeover (CO) contacts for auxiliary signaling — one typically wired to the motor contactor coil, the other to a PLC input or alarm annunciator. There are no dedicated NO or NC contacts; the two COs give flexibility to configure the fail-safe state.
Mounting and wiring in the panel
Housing is 22.5 mm wide, 103 mm tall, 91 mm deep — a standard single-module footprint that clips onto a DIN rail (screw and snap-on mounting). The 22.5 mm width keeps the panel density high; you can fit several evaluation units side by side without crowding the gland plate. Spring-loaded terminals accept solid or ferruled stranded wire. The terminals are rated IP20, so the unit is protected against finger contact but not against moisture ingress — keep it inside the enclosure. An LED on the front confirms the operating status (display version LED: Yes). That helps a field tech quickly see if the unit is powered and whether it has tripped, without needing a meter.
Environmental limits and compliance
Rated for ambient operation from -25 °C to +60 °C — wide enough for most indoor industrial panels, including unheated mill buildings in winter. The storage range is wider, but the operating limit governs the panel's ambient design. The part carries a RoHS compliance date of May 28, 2009, indicating it meets the EU RoHS directive for substances. No UL or CSA mark is stated in the evidence; check the specific nameplate or request certification documents if your site requires them.
Sourcing reality — phased out with a defined successor
For existing BOM lines or installed bases, the 3RN1013-2BB00 can still be sourced through independent channels on a quoted-to-order basis. No last-time-buy date is published; the successor is the recommended path for new designs.