Description
The 6DD1662-0AC0 is a SIMADYN D CS8 Communication Support Module manufactured by Siemens, serving as a two-slot carrier that hosts plug-in communication submodules (COMBOARDs) within SIMADYN D and TDC processor racks. Positioned on the rack’s L-bus alongside PM5/PM6 processors and AP/application modules, the 6DD1662-0AC0 provides the physical, electrical, and buffering infrastructure for up to two independent fieldbus/serial channels — typically a mix of SS4, SS5, SS52, CBP1, CBP2, CBC, CBD, CBI, or CBL plug-ins. Although discontinued by Siemens (PLM PM500, Oct 1, 2017, no direct replacement), the 6DD1662-0AC0 remains a mandatory spare for any SIMADYN D rack that needs fewer than three comm paths and wants to avoid the CS7’s X03 “empty slot” diagnostic nag.
h2 Application Scenarios
On a hot-strip finishing train where the main loop-closure lives on a PM6 in a 19-inch SIMADYN D rack, the original build spec had allocated a CS7 (three-slot carrier) but only ever populated two: X01 = SS4 for DUST1-to-service-laptop plus USS to a closet of legacy SIMOVERT Master Drives, X02 = CBP2 as PROFIBUS DP-V1 master to a retrofitted SINAMICS S120 bookshelf array. The unused X03 kept throwing “CS7 slot empty” into the diagnostic buffer, which the plant’s AMS (Asset Management System) had been scraping as a low-priority alarm for six years — until a corporate audit flagged it as a “nuisance-alarm hygiene” item. The fix wasn’t to populate X03 (there was no third use case), it was to swap the CS7 for a 6DD1662-0AC0 CS8. Same two populated slots, same L-bus mapping, same 16 KB DP-RAM per slot — but the CS8 only has X01 and X02, so the backplane no longer reports a missing X03. The swap took one rack power cycle, the PM6 re-recognized the carrier in twelve seconds, and the audit finding closed. For SIMADYN D estates where “two comm paths is enough,” the 6DD1662-0AC0 is the cleaner carrier — and because it shares the same mechanical keying and L-bus protocol as the CS7, the migration is a one-for-one.
h2 Parameters
| Main Parameters | Value/Description |
|---|---|
| Product Model | 6DD1662-0AC0 (SIMADYN D CS8 Communication Support Module) |
| Manufacturer | Siemens AG |
| Product Category | Communication Support Carrier (2-slot, for plug-in COMBOARDs) |
| Compatible Processors | PM5, PM6 (SIMADYN D); also supported in TDC base racks |
| Slot Capacity | 2 × plug-in receptacles (X01, X02); no X03 (vs. CS7 which has 3) |
| Backplane Bus | L-bus (local bus to PMx / AP / FM458 modules) |
| DP-RAM per Slot | 16 KB dual-port RAM (CPU ↔ plug-in submodule buffer) |
| Supported Plug-Ins | SS4, SS5, SS52, CBP1, CBP2, CBC, CBD, CBI, CBL (PROFIBUS DP, USS, DUST, CAN, DeviceNet, etc.) |
| Supply Voltage | +5 V DC from backplane (~0.5 A + plug-in drain); +15 / –15 V for plug-in analog interface circuits |
| Dimensions (W×H×D) | 18.3 × 233.4 × 220 mm (Eurocard, single-slot SIMADYN D width) |
| Weight | approx. 0.3 kg |
| Protection / Certifications | IP20 (rack-internal); CE, UL, CSA |
| PLC / Lifecycle | PM500 Discontinued (Oct 1, 2017), deleted without replacement |
h2 Technical Principles and Innovative Values
Innovation Point 1: L-Bus Carrier Architecture with Per-Slot DP-RAM. The 6DD1662-0AC0 isn’t a protocol processor — it’s a smart carrier. Each of its two receptacles (X01, X02) is backed by 16 KB of dual-port RAM implemented on the CS8 PCB itself. The PM6 CPU can read/write the DP-RAM at any point in its task cycle while the plugged-in submodule (say, an SS4 running DUST at 115.2 kbps or a CBP2 running PROFIBUS DP at 12 Mbps) independently updates the same buffer. No data collisions, no CPU-scan theft — the comms handle themselves, the PMx picks up the result.
Innovation Point 2: Two-Slot Trim vs. CS7 Three-Slot. The CS7 (6DD1662-0AB0) offers X01/X02/X03. The 6DD1662-0AC0 offers only X01/X02. Electrically the two are near-twins on the L-bus, but the CS8 eliminates the “empty X03” diagnostic artifact that CS7 racks report when only two plugs are populated. For the majority of SIMADYN D racks that need exactly “service channel + fieldbus channel” (very common: SS4 + CBP2), the 6DD1662-0AC0 is the tidier bill-of-materials and avoids spurious alarm traffic to the upstream S7-400/1500 sequence controller.
Innovation Point 3: Protocol Agnosticism via Plug-In Ecosystem. The carrier itself speaks no protocol — the personality comes from whatever you plug into X01/X02. Common field combos on the 6DD1662-0AC0:
- X01 = SS4: DUST1 (engineering/download from PG), USS daisy-chain to SIMOVERT Master Drives over RS-485
- X02 = CBP2: PROFIBUS DP-V1 master @ 12 Mbps to SINAMICS S120, or DP slave to an S7-400/1500 that owns cell sequence
- Alternative: X01 = SS52 (PROFIBUS DP + RS232 monitor), X02 = CBC/CBD for CAN or DeviceNet
One carrier, five-plus protocol families, zero firmware changes to the PM6 application.
Innovation Point 4: EMC-Compliant Slot Shielding. Per the SIMADYN D hardware manual, empty receptacles must be covered with the supplied EMC slot covers, and the module must be tightly screwed to the subrack for noise-immune operation. The 6DD1662-0AC0 ships with the two slot covers plus the front-panel screw; in a thyristor-converter hut (switching harmonics, 6-pulse notching), that grounded cover + L-bus shielding is what keeps the DP-RAM from corrupting during a commutation spike.
h2 Application Cases and Industry Value
