What it is and what it carries
The Siemens 6ES7193-6BP20-2BB1 is a SIMATIC ET 200SP BaseUnit — the mechanical and electrical carrier for a single I/O module in the ET 200SP distributed I/O system. It accepts one Pro-slot I/O module and provides 12 process terminals (push-in type) plus connections to the / power bus and an AUX bus rated at 10 A. The 20 mm width and 35 mm depth keep panel density high; the 117 mm height matches the standard ET 200SP profile. Automatic encoding means the BaseUnit tells the controller which module type is plugged in — no DIP switches or configuration errors on a swap.
Current limits and thermal derating
The AUX bus carries up to 10 A, and the / bus also supports 10 A. Process terminals are limited to 5 A. The part is rated for horizontal installation up to 60 °C and vertical installation up to 50 °C, with a minimum of -30 °C in both orientations. If you are packing modules tight in a vertical cabinet, that 10 °C derating is the number to watch — keep airflow or drop the ambient target.
Panel integration and wiring
Push-in terminals accept 0.14 mm² to 2.5 mm² (AWG 26 to 14) solid or ferruled stranded wire. No screwdriver needed for solid wire — strip to 8–10 mm and push. The BaseUnit snaps onto the DIN rail and bridges the AUX bus to the left neighbor, so you get a continuous potential group without extra jumper wiring. Isolation is tested at 3 100 V DC between the backplane bus and supply voltage.