Description
The 6DD1606-0AD1 is a SIMADYN D T400 Technology Board manufactured by Siemens, built around a 32-bit / 32 MHz digital signal processor and engineered for high-dynamic, microsecond-scale closed-loop control in drive-centric applications. Designed to plug directly into the electronics box of SIMOVERT MASTERDRIVES VC/MC Compact (6SE70/71), the SIMOREG DC-MASTER (6RA70), or the SRT400 SIMADYN D subrack, the 6DD1606-0AD1 offloads demanding process loops—tension control, winder/coiler position, (angular) synchronism, flying saw / cross-cutter timing—from the drive’s own CUVC/CUMC control unit, delivering sampling times down to 100 µs with deterministic execution under D7-SYS / CFC-SFC configuration.
h2 Application Scenarios
On a cold-rolling tandem mill in a Northeast Chinese steel complex, the final stand’s rewinder section was struggling with coil-set and edge-wrinkle rejects during high-speed thread changes. The base 6SE70 MASTERDRIVES VC (CUVC) handled speed loop fine, but the tension-loop math—radius compensation, inertia feed-forward, dancer-carriage PID with diameter calculation from encoder delta—pushed the CUVC’s 2 ms task slice to its limit, and wrinkle rates spiked above 1.8% at >600 m/min. The retrofit solution: drop a 6DD1606-0AD1 T400 into Slot 2 of each rewinder’s 6SE70 electronics box, paired with a CBP2 (PROFIBUS-DP) on the ADB carrier for setpoint handshakes from the S7-400 mill-level controller. The T400 took over tension PID, diameter calc from the two incremental encoder inputs (one on rewind mandrel, one on the dancer pivot arm’s roll), and generated the torque-bias output back to the drive via the local bus. Sampling moved from 2 ms → 100 µs on the tension loop. Three months post-retrofit, wrinkle reject rate dropped to 0.4%, and the mill superintendent noted that “the 6DD1606-0AD1 turned a 1998-vintage drive rack into something that feels like a 2020 drive system, at 5% of a full upgrade cost.” The plant now keeps four refurbished 6DD1606-0AD1 boards on the critical-spare shelf—the T400 is end-of-life, but the 6SE70 racks still have 8–10 years of mechanical life in them.
h2 Parameter
| Main Parameters | Value/Description |
|---|---|
| Product Model | 6DD1606-0AD1 |
| Manufacturer | Siemens (SIMADYN D / T400 Series) |
| Product Category | Technology / Process Board (Drive-Insert) |
| Processor | 32-bit DSP, 32 MHz |
| Memory | 1 MB Flash / 2 MB RAM / 32 KB EEPROM |
| Digital I/O | 8 BE (binary inputs) + 2 BA (binary outputs) + 4 BE/BA (configurable) |
| Analog I/O | 5 AE (analog inputs) + 2 AA (analog outputs) |
| Encoder Interfaces | 2 × incremental encoder inputs; SSI absolute via service IF config |
| Service Interfaces | 2 service IF (+1 SSI) or 1 service IF (+2 SSI) depending on config |
| Sampling Time | Down to 100 µs (process loop) |
| Config / Programming | D7-SYS (CFC / SFC graphical), via PG with SIMADYN D engineering |
| Mounting / Host | SRT400 subrack (up to 2× T400); or Slot 2 of 6SE70/71 & 6RA70 electronics box |
| Lifecycle | End of Product Lifecycle (spare / refurb market only) |
h2 Technical Principles and Innovative Values
Innovation Point 1: Deterministic Sub-100 µs Loop Offload from the Drive CU. The 6DD1606-0AD1 doesn’t replace the 6SE70/6RA70 control unit—it complements it. The CUVC/CUMC still owns the current/speed cascades; the grabs the “slow-but-demanding” process math (tension calc, diameter estimate, synchronism offset, flying-shear trigger angle) and executes at 100 µs sampling over its 32-bit DSP, then writes the torque-bias or speed-setpoint correction back to the drive across the electronics-box local bus. This split-architecture is why a 1990s-era MASTERDRIVES rack can still run world-class tension loops today—the 6DD1606-0AD1 is the secret sauce.
Innovation Point 2: Dual Encoder + SSI Flex for Mechanical Redundancy. The 6DD1606-0AD1 brings two incremental encoder inputs natively, plus SSI absolute-encoder support through the service-interface reconfiguration. On a winding deck, that typically means one encoder on the mandrel (diameter tracking) and one on a dancer-arm pot+encoder or a lay-on-roll tach—giving the both absolute position (SSI from a winder-cradle absolute encoder) and incremental delta for jitter-free diameter calc. The 5 AE / 2 AA analog channels round out the sensor set (dancer LVDT, load-cell amp, drive-analog echo).
Innovation Point 3: D7-SYS CFC/SFC Library of Drive-Process Macros. Siemens ships the 6DD1606-0AD1 “empty”—the 1 MB Flash holds your D7-SYS project, not a fixed firmware. Under D7-SYS you get CFC (Continuous Function Chart) and SFC (Sequential Function Chart) with a prebuilt library: tension-control macro, winder-diameter macro, flying-saw cam macro, synchronous-drive offset macro, etc. A competent drive-engineering team can build a full rewinder tension+diameter+EI-taper project in under two days and download it via the PG into the 6DD1606-0AD1 over the CBP2/SCB link. That’s radically faster than writing the same logic in STARTER/SCOUT on a modern S120—and why legacy mills still cling to .
