The Siemens 6ES7972-0DA00-0AA0 is a SIMATIC DP RS485 terminating resistor designed to physically terminate PROFIBUS or MPI network segments. It screws onto the bus cable via its own screw terminal block for both supply voltage and PROFIBUS cables, drawing a typical 30 mA from a 24 V DC supply (permissible range 20.4 V to 28.8 V DC). The part handles transmission rates from 9.6 kbit/s up to 12 Mbit/s, covering the full PROFIBUS speed range.
The 12 Mbit/s maximum transmission rate matches the top speed of PROFIBUS DP — if your network runs at 1.5 Mbit/s or 12 Mbit/s, this terminator works across the board. The 24 V DC supply with a 20.4 V to 28.8 V tolerance means it can share the same bus power supply as the rest of the segment without a separate regulator. The 60 mm width and 43 mm depth fit a standard DIN-rail footprint alongside other SIMATIC DP components.
Environmental Range
That covers most industrial cabinet environments, including unheated storage areas in cold climates. Power loss is minimal at 0.72 W, so no derating or forced cooling is needed in a typical panel.