Technical Specifications

Main Features and Advantages

The Siemens 6DD1682-0CH2​ delivers a compelling combination of massive scalability, deterministic performance, and industrial robustness that makes it the definitive chassis for SIMATIC TDC high-performance automation systems. Its most defining characteristic is the 64-bit high-speed parallel backplane bus: the Siemens 6DD1682-0CH2​ provides a data superhighway that allows up to 20 CPUs—such as the CPU551 with its 64-bit MIPS R5000 RISC processor—to operate in lockstep synchronization with <1 ms update time across the Global Data Memory. This architectural capability means the Siemens 6DD1682-0CH2​ can scale computational power to unprecedented levels: up to 44 UR5213 racks can be interconnected via fiber-optic GDM links, creating a distributed control system with virtually unlimited processing capacity.Integrated power delivery for complete autonomy:Unlike passive backplanes that require external power supplies, the Siemens 6DD1682-0CH2​ incorporates a complete power subsystem with triple-fan cooling in the upper rack section. The Siemens 6DD1682-0CH2​ converts wide-range 85–264V AC or 198–253V DC input into five regulated DC rails (+5V/36A, +3.3V/44A, +12V/4.6A, -12V/4A) with a total 320W budget—sufficient to power a fully populated rack of CPU551, SM500, CP51M1, CP50M1, and CP52A0 modules simultaneously. The power supply of the Siemens 6DD1682-0CH2​ includes >20 ms hold-up time during power failures, ensuring graceful system behavior during mains interruptions. All outputs are sustained short-circuit-proof and require no minimum load, giving engineers complete freedom in rack configuration.Advanced thermal management:The Siemens 6DD1682-0CH2​ integrates three system fans that provide forced-air cooling across all 21 slots. The fan assembly is continuously monitored—if a single fan fails, the corresponding backplane bus signal (FANAL*) is activated and can be detected by the configuration software, while the power supply itself remains operational. This intelligent fan management of the Siemens 6DD1682-0CH2​ ensures that even in the event of partial cooling degradation, the system continues running while alerting maintenance personnel. The 0°C to +60°C operating range of the Siemens 6DD1682-0CH2​ covers virtually all industrial deployment scenarios.Comprehensive diagnostics and signaling:The Siemens 6DD1682-0CH2​ is engineered for maximum serviceability. Four front-panel status LEDs provide at-a-glance indication of system health, power status, and fan operation. Three floating 230V signaling relays (SYSFAIL, POWER, FAN FAIL) enable external evaluation of rack state—allowing integration with plant-wide alarm systems, DCS, or maintenance management platforms. The Siemens 6DD1682-0CH2​ also includes a battery slot for an AA lithium cell that backs up critical monitoring functions across all 21 slots. These diagnostic capabilities transform the Siemens 6DD1682-0CH2​ from a simple chassis into an intelligent infrastructure component that actively participates in system health management.GDM-optimized 5-row connector:The Siemens 6DD1682-0CH2​ features a 5-row female connector specifically designed for Global Data Memory (GDM) expansion. This connector allows the rack to participate in fiber-optic GDM networks linking up to 44 UR5213 racks, enabling synchronization of scan time and clock time, shared alarm functions, and near-unlimited expansion of computing power. The GDM architecture of the Siemens 6DD1682-0CH2​ is what makes SIMATIC TDC the platform of choice for the world’s most demanding multi-axis, multi-rack control applications.Critical legacy system enabler:The Siemens 6DD1682-0CH2​ holds the distinction of being explicitly “deleted without replacement” by Siemens (PM500). While the newer UR6021 (6DD1682-0CH3) can serve as a substitute, it comes with restrictions—new CPU555 modules cannot be used with old modules in UR6021, and a different backup battery (3.6V 2.3Ah, 6ES7971-0BA00) is required. For existing UR5213-based systems, the Siemens 6DD1682-0CH2​ remains the only fully compatible chassis. This makes the Siemens 6DD1682-0CH2​ an absolute necessity for plants operating SIMATIC TDC—a failed rack chassis can halt an entire production line, and with no direct alternative available, having genuine Siemens 6DD1682-0CH2​ units in strategic stock is the only way to protect against catastrophic unplanned downtime.