Product Overview

The Siemens 6DD1660-0BF0​ is a SIMATIC TDC Communication Module designated CP 52M0, configured specifically as a Global Data Memory (GDM) expansion module carrying 2 MB of SRAM. While the 6DD1660 family broadly covers communication processors within the SIMATIC TDC rack ecosystem, the Siemens 6DD1660-0BF0​ variant is the memory-centric subtype — its role is to provide shared, deterministic data-exchange space that multiple TDC CPU modules (PM6, PM7, or FM458-1DP-based multicore CPUs in a TDC rack) can read and write with minimal latency, without saturating the 64-bit TDC backplane with message traffic.SIMATIC TDC itself is Siemens’ highest-tier multi-processor control platform, positioned above SIMADYN D and S7-400 in raw I/O bandwidth and closed-loop update rate, targeting applications where microsecond-level determinism and thousands of I/O across distributed racks matter — multi-stand rolling mills, paper-machine drive sections, hydro generator excitation multi-rack, full-vehicle engine/dynamometer test rigs, wind tunnels, and large crane sync systems. In that architecture, the GDM sits on a dedicated rack (UR5213, 21-slot) that is separate from the CPU racks (UR5214/UR5225). The Siemens 6DD1660-0BF0​ occupies slot 1 of the UR5213 GDM rack as the CP 52M0 memory hub; slots 2–12 carry CP52IO interface modules that star-connect via duplex SC fiber (62.5/125 µm, up to 200 m) to CP52A0 access modules in each coupled CPU subrack. Up to 44 subracks can be coupled synchronously through one GDM, meaning a maximum of 836 TDC CPU modules share the 2 MB SRAM pool on the Siemens 6DD1660-0BF0.Physically, the Siemens 6DD1660-0BF0​ is a narrow-format module — 20 mm width (single TDC slot), 233 mm height, 160 mm depth, ~0.465 kg — drawing 5 V / 3.3 V / ±12 V from the TDC rack backplane (typical 4.5 W loss), no separate PSU. The 2 MB SRAM is battery-backed through the UR5213 rack’s central backup concept (battery/supercap on the rack PSU), so GDM contents survive controlled shutdowns. Siemens placed the Siemens 6DD1660-0BF0​ into PM400 “Phase-Out Started” effective 01.10.2023, meaning new orders from Siemens direct are closing and the module now lives in the aftermarket/spare-channel lifecycle. For plants running active multi-rack TDC cells, maintaining a shelf of Siemens 6DD1660-0BF0​ units is the pragmatic way to protect uptime without undertaking a TDC→SINAMICS/SIMOTION/S7-1500 R/H migration, which for a multi-rack TDC cell is a major capital project.

Technical Specifications