BaseUnit for ET 200SP — what fits and what doesn't
The Siemens 6ES7193-6BP00-0BU0 is a SIMATIC ET 200SP BaseUnit, type BU20-P16+A0+2B, that mounts on the standard DIN rail and accepts one I/O module in its single slot. It carries 16 process terminals to the I/O module and two terminals for the and bus, with push-in termination that accepts 0.14 to 2.5 mm² conductors. The 20 mm width keeps the slice footprint tight on a crowded rail.
Ratings and thermal limits
The AUX bus and the / bus are rated at 277 V, with a maximum current of 10 A for the AUX bus and 10 A for the / bus. The process terminals also carry a 10 A maximum, but with a derating note — the actual limit depends on the module plugged in. Horizontally installed, the BaseUnit runs from -30 °C to 60 °C; vertical installation derates the top end to 50 °C. Installation altitude goes up to 3000 m without special treatment.
Bus continuity and encoding
This BaseUnit continues the potential group from the left — no new group starts here. It bridges the AUX bus at 277 V and ties the equal potential group to the / bus or PE. Automatic encoding (FS11 and later) means the module is keyed on insertion; no manual DIP-switch setting for the slot address. The optional system-integrated shield connection lets you clamp a cable shield directly to the BaseUnit, which saves a separate grounding terminal.