Siemens 6ES7972-0DA00-0AA0 SIMATIC DP Terminating Resistor

The Siemens 6ES7972-0DA00-0AA0, also cataloged as the 6ES7972-0DA00-0AA0 Terminating Resistor, serves as the primary SIMATIC DP Terminating Resistor utilized to execute electrical line termination across PROFIBUS and MPI network segments. It stabilizes physical wave reflections and signal differential voltages natively at the bus segment endpoints via a dedicated 24 VDC active bias configuration to maintain communication integrity parallel to master control network platforms.

Hardware Specifications

Industrial Control & Drive Integration

• Backplane Bus Communication Velocity Licences and Segment Stability: The active terminating resistor provides stationary line biasing independent of the operational states of individual connected PLC nodes. This continuous potential layout maintains the signal voltage levels, preventing data dropouts that could degrade backplane bus communication velocity parameters across upstream master controllers.
• Profinet / EtherNet/IP Deterministic Networks Coexistence: While high-level architectures route primary plant telemetry over Profinet / EtherNet/IP deterministic networks, this module continuously balances the underlying serial layers. By absorbing signaling wave echoes, it maintains quiet RS-485 signaling zones free from data corruption.
• I/O Density Scaling and Continuous Line Biasing: This active component permits individual network nodes at the end of the trunk to be switched off or hot-swapped without destabilizing the bus topology. It maintains line matching for the remaining active nodes, ensuring continuous operation during localized I/O density scaling adjustments or module swaps.

Frequently Asked Questions

Q: What specific hardware behaviors manifest if the external 24 VDC power supply to this active terminating resistor is cut off?

A: Without active 24 VDC power, the internal bias resistors lose their potential reference points, reducing the network's noise margin. This state often causes intermittent frame corruption, checksum errors, or a total breakdown of communication on the connected serial segment.

Q: Can this unit be used to replace standard passive connectors with integrated slide switches at intermediate network drops?

A: No. This module is an active terminal block designed strictly for the physical ends of a network line. Installing it at an intermediate drop would bridge the line topology inappropriately, attenuating the signal amplitude and disrupting communications across the bus.