SIEMENS 6ES7241-1CH30-0XB0 CB 1241 RS485 Communication Board – SIMATIC S7-1200 Series
Imagine a critical production line where your S7-1200 PLC needs to exchange real-time data with legacy serial devices — barcode scanners, variable frequency drives, weighing terminals, or third-party SCADA systems — but lacks a native RS-485 port. Without the CB 1241 communication board, engineers are forced into costly workarounds: additional gateway hardware, complex protocol converters, or complete system redesigns that delay commissioning by weeks. The SIEMENS 6ES7241-1CH30-0XB0 eliminates this bottleneck entirely, plugging directly onto the S7-1200 CPU board to deliver a dedicated RS-485/RS-232 serial interface with zero footprint expansion.
The 6ES7241-1CH30-0XB0 is the CB 1241 RS485 communication board — a compact, board-level expansion module designed exclusively for the SIMATIC S7-1200 CPU family. Within the S7-1200 ecosystem, it occupies a unique position: unlike signal boards (SBs) that handle I/O, the CB 1241 is purpose-built for serial communication, supporting both RS-485 and RS-232 interfaces via software configuration. It is widely deployed across global manufacturing, water treatment, building automation, and energy management sectors, making it one of the most specified serial expansion options for S7-1200 installations worldwide.
Technical Specifications
- Order Number (MLFB): 6ES7241-1CH30-0XB0
- Product Family: SIMATIC S7-1200, CB 1241
- Interface Type: RS-485 / RS-232 (software selectable)
- Connector: 9-pin D-sub (RS-232) / Terminal block (RS-485)
- Supported Protocols: USS, Modbus RTU, Freeport (ASCII/binary)
- Baud Rate: 300 bps to 115.2 kbps
- Supply Voltage: 5 VDC (supplied by CPU)
- Dimensions (W×H×D): 38 × 62 × 21 mm
- Weight: Approx. 120 g
- Operating Temperature: 0 °C to +60 °C
- Storage Temperature: −40 °C to +70 °C
- Degree of Protection: IP20
- Compatible CPUs: S7-1200 CPU 1211C, 1212C, 1214C, 1215C, 1217C (firmware V2.0 and above)
- Firmware: V2.1 and above supported
- Certifications: CE, UL, cULus, ATEX (Zone 2)
Key Features & Benefits
- Dual-mode serial interface: Supports RS-485 (2-wire, half-duplex) and RS-232 (full-duplex) via software selection — one board, two protocols.
- Board-level installation: Mounts directly on the CPU front panel without consuming DIN rail space or requiring additional power supply.
- Native Modbus RTU master/slave: Enables direct communication with thousands of Modbus-compatible field devices without additional gateways.
- USS protocol support: Seamlessly controls Siemens SINAMICS and MICROMASTER drives via the integrated USS library in TIA Portal.
- Freeport mode: Flexible ASCII/binary communication for custom serial protocols and third-party device integration.
- TIA Portal integration: Fully configured within STEP 7 Basic / TIA Portal V13 SP1 and above — no external configuration tools required.
- Compact form factor: Minimal footprint preserves panel space in space-constrained control cabinets.
- Industrial-grade reliability: Designed for 24/7 continuous operation in harsh industrial environments up to 60 °C.
Industry & Equipment Applications
- Manufacturing & Assembly: Serial communication with barcode readers, label printers, and vision systems on production lines.
- Water & Wastewater Treatment: Modbus RTU polling of flow meters, level sensors, and dosing pump controllers.
- Building Automation (BAS/BMS): Integration with HVAC controllers, energy meters, and access control systems via RS-485 bus.
- Energy Management: Data acquisition from power analyzers and smart meters using Modbus RTU protocol.
- Drive Control: USS protocol communication with SINAMICS G120, V20, and MICROMASTER 440 frequency inverters.
- Food & Beverage: Hygienic process control with serial-connected weighing and filling equipment.
- Oil & Gas: Remote terminal unit (RTU) communication in pipeline monitoring and pump station automation.
System Integration & Compatible Parts
The 6ES7241-1CH30-0XB0 is designed to integrate seamlessly within the SIMATIC S7-1200 ecosystem. Compatible and commonly paired components include:
- Host CPUs: 6ES7211-1AE40-0XB0 (CPU 1211C), 6ES7214-1AG40-0XB0 (CPU 1214C), 6ES7215-1AG40-0XB0 (CPU 1215C)
- Signal Boards: 6ES7221-3BD30-0XB0 (SB 1221 DI), 6ES7232-4HA30-0XB0 (SB 1232 AO)
- Communication Modules: 6ES7241-1AH30-0XB0 (CM 1241 RS232), 6ES7241-1CH30-1XB0 (CM 1241 RS485)
- Power Supplies: 6EP1332-1SH71 (SITOP PSU100S 24VDC/5A)
- Programming Software: TIA Portal V15.1 / V16 / V17 / V18 / V19
Our Quality Assurance Process
At Konmask.com, every SIEMENS 6ES7241-1CH30-0XB0 unit goes through a rigorous sourcing and verification process before dispatch:
- Authentic sourcing: All units are sourced from authorized distributors and verified supply chains — no grey-market or counterfeit parts.
- Visual & label inspection: Each unit is inspected for intact Siemens holographic labels, correct MLFB markings, and undamaged packaging.
- Functional verification: Where applicable, modules are bench-tested for power-on response and communication port integrity.
- ESD-safe packaging: All modules are shipped in anti-static bags with foam cushioning to prevent transit damage.
- Traceability: Batch and serial number records are maintained for full supply chain traceability.
How to Order
- Submit an inquiry via the Contact Us page or email support@konmask.com with your required quantity and delivery timeline.
- Receive a formal quotation with unit price, lead time, and shipping options within 24 business hours.
- Confirm the purchase order — we accept T/T bank transfer, PayPal, and other B2B payment methods.
- Shipment via DHL / FedEx / UPS with full tracking and commercial invoice provided.
- Post-delivery technical support available for integration and commissioning questions.
Why Choose Konmask.com?
- ✅ Specialized in industrial automation components — PLC, DCS, HMI, drives, and communication modules from leading global brands.
- ✅ B2B-focused service — dedicated account management, volume pricing, and flexible payment terms for OEMs, system integrators, and MRO buyers.
- ✅ Global shipping — reliable export logistics to 50+ countries with full customs documentation support.
- ✅ Technical expertise — our team includes experienced automation engineers who can advise on compatibility, substitution, and system design.
- ✅ Fast response — inquiry-to-quote within 24 hours; urgent orders prioritized.
- ✅ Warranty & after-sales — all products covered by our quality guarantee with clear return and replacement policy.
Frequently Asked Questions
- Q: What is the difference between 6ES7241-1CH30-0XB0 (CB 1241) and 6ES7241-1CH30-1XB0 (CM 1241)?
- A: The CB 1241 (0XB0) is a communication board that mounts directly on the CPU front panel and is powered by the CPU — it does not occupy a module slot. The CM 1241 (1XB0) is a communication module that installs in the left-side expansion slot and supports longer cable runs. Choose CB 1241 for space-saving installations; CM 1241 for extended RS-485 networks.
- Q: Can the 6ES7241-1CH30-0XB0 be used as a Modbus RTU master and slave simultaneously?
- A: No. The CB 1241 supports one active communication mode at a time — either Modbus RTU master or slave, configured in TIA Portal. Simultaneous master/slave operation on the same port is not supported.
- Q: Which TIA Portal version is required to configure the 6ES7241-1CH30-0XB0?
- A: TIA Portal V13 SP1 or higher is required. Siemens recommends using the latest available version (V19 as of 2026) for full feature support and security patches.
- Q: Is the CB 1241 compatible with S7-1200 CPUs running firmware V4.x?
- A: Yes. The 6ES7241-1CH30-0XB0 is compatible with all S7-1200 CPU firmware versions from V2.0 onwards, including V4.x and V4.5.
- Q: Do you provide a certificate of conformity or test report with the shipment?
- A: Yes. Upon request, we can provide available documentation including CE declaration of conformity and inspection records. Please specify your documentation requirements when placing your inquiry.
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Original Source: https://Konmask.com
Contact: support@konmask.com | +0086 19859288691
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