SIMATIC CPU Central Processing Unit 6ES7416-2XN05-0AB0 6ES7 416-2XN05-0AB0 6ES7416-2XNO5-OABO

6ES7416-2XN05-0AB0 | SIMATIC S7-400 CPU 416-2 — 5.6MB Working Memory / MPI/DP + PROFIBUS DP / CiR / 21 Expansion Units / 4.5W 

5.6MB of Working Memory — The CPU 416-2 in the S7-400 Range

The CPU 416-2 sits near the top of the SIMATIC S7-400 CPU family. Its 5.6MB working memory — split equally between 2.8MB code and 2.8MB data — accommodates the largest and most complex S7-400 programmes. Hundreds of PID loops, extensive PROFIBUS I/O with large process image tables, recipe databases, diagnostic alarm buffers, and historian data structures all fit within this memory allocation without the programme developer having to manage memory constraints in the user code.

The two built-in communication interfaces provide independent network domains. The MPI/DP combined interface handles either MPI (for programming terminals and HMI) or PROFIBUS DP master/slave operation. The dedicated PROFIBUS DP second interface adds a second independent DP network. Two DP master networks allow large S7-400 installations to separate drive networks from instrumentation networks, keeping their traffic profiles isolated.

Twenty-one expansion unit slots support extensive I/O infrastructure directly from this CPU. Combined with PROFIBUS DP distributed I/O on both interfaces, the CPU 416-2 scales to the largest continuous process automation configurations.

Key Specifications

CiR — Configuration in Run

CiR (Configuration in RUN) allows the S7-400 system configuration — adding or modifying I/O modules, PROFIBUS DP slaves, and their address assignments — while the CPU continues executing the user programme and controlling outputs. The CPU 416-2 supports CiR with a basic synchronisation time of −100ms and an incremental time of 10µs per I/O byte involved in the change. This capability eliminates planned shutdowns for configuration changes in production environments where continuous operation is a requirement.

Application Scenarios

Large-scale process control: Oil and gas processing, chemical reactors, power generation, and large water treatment installations where programme complexity demands maximum memory.

Multi-network PROFIBUS architectures: Separate DP networks for variable-speed drives and process instrumentation — each on its own interface, each running at optimised baud rates.

Maintenance spare for installed CPU 416-2 systems: An exact part number match preserves the programme, hardware configuration, and communication architecture of the installed system.

FAQ

Q1: What is the difference between the CPU 416-2 (6ES7416-2XN05-0AB0) and the CPU 416-3?

The CPU 416-2 has 5.6MB working memory and two interfaces (MPI/DP + DP). The CPU 416-3 has 3.2MB working memory but adds a third interface (IFM) for direct inter-rack synchronisation. Choose the 416-2 for maximum memory; choose the 416-3 when the third IFM interface is required for the installed system architecture.

Q2: What does the successor 6ES7416-2XP07-0AB0 provide over this unit?

The 6ES7416-2XP07-0AB0 (CPU 416-2, XP07 variant) provides 8MB working memory (4MB code + 4MB data), compared to 5.6MB for this unit. Both carry the same MPI/DP and PROFIBUS DP interface pair and are physically compatible with the same S7-400 racks.

Q3: Can the CPU 416-2 operate in S7-400H redundant systems?

No. Redundant S7-400H configurations require specifically designated H-class CPUs (CPU 412H, CPU 414H, CPU 417H) with synchronisation module interfaces. The standard CPU 416-2 is for non-redundant S7-400 systems. An H-class CPU must be specified if hot-standby redundancy is required.

Q4: Does this CPU support STEP 7 Classic only, or also TIA Portal?

The CPU 416-2 is programmed with STEP 7 Classic (V5.x). TIA Portal supports standard S7-400 CPUs in certain configurations, but engineering and legacy programme maintenance for installed CPU 416-2 systems is typically done in STEP 7 Classic. Verify TIA Portal compatibility with the specific installed firmware revision.

Q5: What is the significance of the −100ms CiR basic load value?

The negative value indicates that for CiR changes with a basic complexity (no additional I/O bytes), the CPU cycle time can be shortened rather than extended during the reconfiguration event. The 10µs per I/O byte term adds scan time proportionally for each byte of I/O involved in the change. For changes affecting many I/O bytes, the total CiR synchronisation time equals −100ms plus (n × 10µs), where n is the number of I/O bytes.