Siemens SIMADYN D Modules: 6DD1640-0AC0

Technical Dossier

Product Details And Specifications

Siemens SIMADYN D Series Technical Notes

The Siemens SIMADYN D is a modular, rack-based digital control system developed by Siemens AG for high-demand industrial process control applications. It holds a significant installed base across global heavy industry sectors including petrochemical plants, nuclear power stations, oil refineries, steel mills, and large-scale drive systems. The system architecture is built around a VMEbus backplane, enabling deterministic real-time processing with cycle times in the sub-millisecond range. SIMADYN D was engineered to replace relay-based and analog control panels in continuous process environments where uptime, precision, and long-term serviceability are non-negotiable requirements. Its modular design allows individual function modules — processors, I/O cards, communication adapters, and power supplies — to be replaced independently without full system shutdown, a critical feature for facilities operating 24/7.

The Evolution of SIMADYN D Architecture

SIMADYN D was introduced in the mid-1980s as the successor to the SIMADYN C analog control platform. The transition from analog to digital signal processing marked a fundamental shift in how Siemens approached closed-loop control for drives and process automation. Early SIMADYN D configurations relied on the PM5 and PM6 processor modules operating at relatively modest clock speeds, with I/O expansion handled through dedicated analog and digital interface cards connected via the VMEbus.

Through the 1990s, Siemens introduced the PM10 and PM21 processor families, significantly increasing computational throughput and enabling more complex multi-loop control strategies within a single rack. Communication capabilities expanded with the introduction of CS31 bus adapters and PROFIBUS-DP interface modules, allowing SIMADYN D to integrate into broader plant-wide DCS architectures alongside SIMATIC S5 and later SIMATIC S7 systems.

By the 2000s, SIMADYN D had entered its mature phase. Siemens formally announced the migration path toward SIMATIC TDC (Technology and Drive Control), which shares functional equivalence with SIMADYN D but is built on a modern hardware platform with extended processor performance and current production status. Many end users operating SIMADYN D installations have elected to maintain the existing platform rather than undertake full system replacement, given the engineering cost and process risk involved. This has created sustained demand for original spare modules, tested refurbished units, and lifecycle extension services.

SIMADYN D Full Catalog & Functionalities (SKU List)

Processor Modules (CPU)

• 6DD1600-0AE0: PM5 processor module, VMEbus master, 16-bit architecture for basic closed-loop control tasks.
• 6DD1600-0AF0: PM6 processor module, enhanced cycle time performance over PM5, supports expanded I/O addressing.
• 6DD1600-0AG0: PM10 processor module, 32-bit processing, multi-tasking real-time OS, primary CPU for mid-complexity applications.
• 6DD1600-0AH0: PM21 processor module, high-speed 32-bit CPU, supports parallel processing configurations in multi-rack systems.
• 6DD1600-0BA0: PM22 processor module, extended memory capacity, optimized for large-scale drive control and multi-axis coordination.

Analog I/O Modules

• 6DD1640-0AC0: AM10 analog I/O module, 8-channel ±10V/±20mA input/output, 12-bit resolution, used for process variable acquisition and setpoint output in drive and process control loops.
• 6DD1640-0AB0: AM6 analog input module, 6-channel differential analog input, 14-bit resolution, suited for precision measurement in temperature and pressure control loops.
• 6DD1641-0AA0: AM50 analog output module, 8-channel isolated analog output, 12-bit DAC, used for actuator and drive reference signal generation.
• 6DD1642-0AA0: AM60 high-resolution analog input module, 16-bit ADC, 4-channel differential, for precision instrumentation interfaces.

Digital I/O Modules

• 6DD1660-0AA0: DM10 digital I/O module, 16 DI / 16 DO, 24VDC, standard binary signal interface for status monitoring and relay output control.
• 6DD1660-0AB0: DM20 digital input module, 32-channel 24VDC DI, high-density binary input for large-scale interlock and status acquisition.
• 6DD1661-0AA0: DM30 digital output module, 16-channel relay output, rated for inductive loads, used in motor starter and valve control circuits.
• 6DD1662-0AA0: DM40 fast digital I/O module, hardware interrupt capability, used for encoder position capture and high-speed event detection.

Communication & Interface Modules

• 6DD1681-0AA0: CS31 bus adapter module, connects SIMADYN D rack to Siemens CS31 remote I/O bus, extends I/O capacity without additional VMEbus slots.
• 6DD1682-0AA0: PROFIBUS-DP interface module, enables SIMADYN D integration into PROFIBUS networks as master or slave station.
• 6DD1683-0AA0: Ethernet TCP/IP communication module, supports supervisory data exchange with SCADA and DCS host systems.

Power Supply Modules

• 6DD1680-0AA0: PS5 rack power supply, 5VDC/10A output for VMEbus backplane, primary power source for standard SIMADYN D rack configurations.
• 6DD1680-0AB0: PS10 dual-output power supply, 5VDC and ±15VDC outputs, required for racks containing analog I/O modules with bipolar supply requirements.

Sourcing Hard-to-Find & Obsolete SIMADYN D Parts

Siemens officially discontinued active production of SIMADYN D hardware, with the recommended migration path being SIMATIC TDC. However, the installed base of SIMADYN D systems in continuous process industries — particularly in facilities with 20–40 year asset lifecycles — means that demand for original and refurbished spare modules remains active globally.

Quality Control for the SIMADYN D Range

SIMADYN D modules present specific testing challenges due to their VMEbus backplane communication architecture and mixed analog/digital signal paths. DriveKNMS applies a structured test protocol for all SIMADYN D units processed through its facility.