Description
Siemens 6GK5212-2BB00-2AA3 | SCALANCE X212-2 Managed Switch
Architect’s Product Breakdown
The Siemens 6GK5212-2BB00-2AA3 (SCALANCE X212-2) is a high-density managed Industrial Ethernet switch engineered for large control cabinets requiring extensive local RJ45 connections alongside long-distance optical uplinks. Equipped with 12 RJ45 ports and 2 multimode BFOC (ST) fiber interfaces, this unit acts as a central star or line hub within factory floor cells.
The integration of two 100 Mbps BFOC optical ports allows engineers to build noise-immune glass fiber backbones up to 5 kilometers long. This isolates network lines passing between buildings, outdoor substations, or areas with high electromagnetic interference (EMI), such as heavy motor drives and induction furnaces.
Operating as a full PROFINET IO device, the X212-2 integrates directly into TIA Portal and STEP 7 engineering environments. PLC logic can monitor port link states, cable break faults, and power supply health via standard PROFINET alarms. It includes an integrated Redundancy Manager (RM) for High-Speed Redundancy (HSR) and Media Redundancy Protocol (MRP) rings, alongside an optional C-PLUG slot for rapid, parameter-free hardware swaps.
6GK5212-2BB00-2AA3
Key Technical Specifications
| Parameter | Technical Specification |
| Manufacturer | Siemens AG |
| Product Line | SCALANCE X-200 (Compact Managed Switch) |
| Copper Interfaces | 12x RJ45 Ports (10/100 Mbit/s, Auto-Sensing / Auto-Crossover) |
| Optical Interfaces | 2x Multimode 100 Mbit/s BFOC (ST) Sockets |
| Max Optical Range | Up to 5 km (using 50/125 µm or 62.5/125 µm Glass Fiber) |
| Network Protocols | PROFINET IO Device, Web-Based Management (WBM), SNMP v1/v2/v3 |
| Redundancy Protocols | Integrated Redundancy Manager (RM), MRP (Media Redundancy Protocol) |
| Supply Voltage | Dual Redundant 24 VDC (Range: 18 VDC to 32 VDC) |
| Signal Contact | 1x Fault Signaling Relay Output with SET Button |
| Configuration Backup | Optional C-PLUG Slot (Removable Media) |
| Operating Temperature | -40°C to +60°C (-40°F to 140°F) |
Field Engineer’s Pitfall Guide (Unique Value)
- CROSSING TRANSMIT/RECEIVE FIBER LEADS: Always verify Tx and Rx crossover when terminating BFOC connectors. Unlike copper RJ45 ports with Auto-MDIX, optical ports cannot automatically swap transmit and receive paths. The Tx socket on Port 13/14 must connect directly to the Rx socket on the far-end device; crossing these leads will result in no link light and loss of communication.
- EXCEEDING BEND RADIUS ON GLASS FIBER CABLES: Maintain a minimum bend radius of at least 10 times the cable diameter. Sharp bends inside cabinet trunking cause light leakage and signal attenuation, which manifests as intermittent packet drops or high CRC error rates in the switch’s Web-Based Management (WBM) diagnostic log.
- LEAVING BFOC OPTICAL PORTS UNPROTECTED: Keep protective dust caps installed on unused optical sockets. Dust or airborne oil mist inside an exposed BFOC socket will dirty the internal lens, causing severe optical signal loss when a patch cable is eventually connected.
QA & Testing SOP (Transparency)
- Visual & Port Hardware Audit: Inspection of all 12 RJ45 spring contacts, BFOC ceramic ferrules, terminal block screws, and DIN-rail mounting latches.
- Power Supply & Relay Validation: Redundant 24 VDC power channels tested under load; fault signaling contact trip point verified by dropping voltage on Input L1.
- Optical Power & Link Testing: BFOC optical ports tested with a calibrated optical power meter to confirm transmit levels stay within spec (-19 dBm to -14 dBm).
- Traffic Burn-In & MRP Ring Test: Full wire-speed packet traffic injected across all 14 ports for 4 hours; ring failover latency verified under 200 ms inside an MRP loop.
- Clean OS Reset & Anti-Static Pack: Factory IP configuration restored, optical dust caps fitted, unit sealed in static-shielding bags, and packed in reinforced foam shipping boxes.
Technical FAQ
What type of fiber cables are required for the 6GK5212-2BB00-2AA3?
This switch uses multimode glass fiber optic cables (either 50/125 µm or 62.5/125 µm) terminated with BFOC (ST) bayonet connectors. It is not compatible with single-mode fiber or plastic optical fiber (POF) lines.
What is the maximum distance supported by the fiber ports?
The multimode BFOC optical interfaces support distances up to 5 kilometers without signal repeaters, provided cable attenuation remains within normal operating tolerances.
Can I run this switch without configuring it in TIA Portal?
Yes. Out of the box, the SCALANCE X212-2 operates as an unmanaged Layer 2 switch with default settings. However, to utilize managed features such as VLANs, MRP ring redundancy, and PROFINET diagnostic reporting, you can configure it via its internal Web-Based Management (WBM) or import its GSDML file into TIA Portal / STEP 7.
How does the SET button next to the signaling contact work?
The SET button calibrates the fault monitoring baseline. When pressed, the switch records all currently connected ports as the “normal” state. If any monitored link drops unexpectedly afterward, the internal fault relay opens to alert an upstream PLC or alarm horn.
Does the switch include a C-PLUG, or is it purchased separately?
The C-PLUG configuration storage plug is optional and sold separately (order code 6GK1900-0AB00). When installed, it automatically backs up all switch settings, allowing an instant hardware swap if the unit is damaged in the field.
