The Siemens 3RK1301-0AB10-1AB4 is a SIMATIC-branded reversing motor starter — a single device that handles forward/reverse control of a three-phase motor without external contactors. It integrates the reversing contactor pair, overload protection, and fieldbus interface in one 130 mm wide housing that plugs onto a terminal module (fastening method: pluggable on terminal module). This is a panel-mount unit sized for a standard enclosure; the 150 mm depth and 290 mm height leave room for wiring ducts and gland plates on a typical 600 mm deep cabinet. Rated supply is 24 V DC (20.4 to 28.8 V permissible range), which powers the internal electronics and coil. The starter accepts two digital inputs for start/stop and direction commands, and it reports status via 2 bytes of input data and 2 bytes of output data on the fieldbus.
The overload relay is adjustable to trip class 5, 10, 15, or 20. That means the thermal model trips in 5, 10, 15, or 20 seconds at 7.2× the set current. For a pump or fan with a slow acceleration curve, class 20 gives the motor time to start without nuisance tripping; for a fast-cycling conveyor, class 5 keeps the winding protected. The reversing function is built in (reverse starting: Yes), so the same unit handles direction change without an extra contactor. Direct start is not supported — this is strictly a reversing starter, not a non-reversing one.
Fieldbus and environmental limits
Both PROFINET and PROFIBUS DP protocols are on board — the starter can be addressed as a standard IO device on either network. Vibration resistance is 2g, shock resistance 5g at 11 ms, which covers most industrial machinery (conveyors, machine tools, packaging lines). Pollution degree 3 at 400 V and 2 at 500 V per IEC 60664 / IEC 61131 means it's rated for industrial environments with conductive dust or occasional condensation.