Siemens DDC TXM1.8X-ML Universal Module

The Siemens DDC TXM1.8X-ML Universal Module is a high-performance TX-I/O™ component designed for seamless integration into Desigo building automation systems. Engineered for versatile field-level control, this module features eight individually configurable I/O points that support digital inputs (maintained, pulse, or counter), analog inputs (0..10V, 4..20mA, or resistance sensors), and analog outputs (0..10V, 4..20mA on points 5-8). As a veteran technician knows, the "ML" designation is critical, signifying the integrated LCD display and local override facility, allowing for immediate point diagnostics and manual control as per ISO 16484-2 and VDI 3814 standards. Its DIN rail mounting footprint is compact, utilizing a separate terminal base and plug-in module architecture that simplifies system commissioning. Use these modules to streamline control cabinet wiring by utilizing self-establishing bus connections, which eliminate the need for complicated internal jumpers when scaling your PXC automation station.

• Universal Port Flexibility: Each of the 8 points can be independently mapped for DI, AI, or AO (points 5-8) to match specific field device requirements.
• Local Override Control: Integrated LCD and manual switches allow for direct field-level troubleshooting without needing a laptop or front-end access.
• Hot-Swappable Design: The plug-in electronics module can be replaced in seconds without disturbing existing field wiring on the terminal base.
• Superior Signal Processing: Supports precise 4-20mA monitoring and high-speed counter pulses up to 100 Hz for accurate flow and energy metering.
• DIN Rail Efficiency: Compact 64mm width minimizes panel space while providing high density I/O capability for HVACR applications.

Common Questions

How do I configure the signal type for each point?
Signal configuration is handled through the Desigo toolset (such as ABT Site). However, the TXM1.8X-ML provides local feedback on the LCD, displaying the current signal type and real-time process value for each of the eight points, which is invaluable during initial startup.

Can I use this module for safety-critical hardware interlocks?
No, following industry standards, the local override facility on the module executes commands directly without software interlocks. All safety-relevant functions (like high-pressure cutouts or fire shutdowns) must be implemented with external, hardwired solutions.

Is the terminal base included with the plug-in module?
Typically, the TX-I/O system utilizes separate components. This product is the plug-in I/O module. Ensure your terminal base (TXS1.S or similar) and the appropriate address key are installed in the cabinet before mounting this unit.

What happens to the remaining modules if I pull one TXM1.8X-ML for service?
The TX-I/O bus is designed for continuity. Pulling an I/O module into the "parking" position or removing it entirely does not interrupt the communication bus, allowing the rest of the PXC Series island to function normally.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.