Siemens SIMATIC S7-400H Modules: 6ES7414-4HR14-0AB0

Technical Dossier

Product Details And Specifications

Siemens SIMATIC S7-400H Series Technical Notes

The Evolution of SIMATIC S7-400H Architecture

The S7-400H platform was introduced in the mid-1990s as Siemens' response to demand for IEC 61508-compliant redundant control in process automation. The first-generation CPUs — including the 6ES7414-4HJ00-0AB0 — established the dual-CPU synchronization model using fiber-optic sync cables and the proprietary H-Sync protocol. These early units supported STEP 7 v5.x exclusively and operated on the S7-400 UR2-H rack.

The second generation, represented by the 6ES7414-4HM14-0AB0 and 6ES7417-4HT14-0AB0, introduced expanded working memory (up to 30 MB), faster cycle times, and compatibility with PROFINET IO redundancy (S2 and R1 system redundancy modes). These CPUs also added support for isochronous PROFIBUS DP, enabling tighter synchronization with distributed I/O in high-speed process loops.

The current generation — including the 6ES7414-4HR14-0AB0 — represents the mature phase of the S7-400H lifecycle. Siemens has formally announced the S7-400 family as a product in the sustaining phase, with the SIMATIC S7-1500H (redundant variant of the S7-1500) positioned as the long-term migration target. Compatibility between S7-400H and S7-1500H requires full project re-engineering; there is no direct hardware migration path. For plants committed to S7-400H for the duration of their current asset lifecycle (typically 15–25 years for process facilities), long-term spare parts availability is the primary operational concern.

SIMATIC S7-400H Full Catalog & Functionalities (SKU List)

CPU Modules (Redundant)

• 6ES7414-4HR14-0AB0: S7-400H redundant CPU, 4 MB work memory, PROFIBUS DP integrated, H-Sync via fiber
• 6ES7414-4HM14-0AB0: S7-400H CPU, 8 MB work memory, PROFINET IO support, dual-port Ethernet
• 6ES7417-4HT14-0AB0: High-end S7-400H CPU, 30 MB work memory, extended instruction set, PROFINET IRT
• 6ES7414-4HJ00-0AB0: First-generation S7-400H CPU, 512 KB work memory, PROFIBUS DP only (obsolete)
• 6ES7417-4HL04-0AB0: S7-400H CPU, 16 MB work memory, PROFIBUS DP + MPI, legacy sync protocol

Synchronization Modules

• 6ES7960-1AA04-0XA0: H-Sync fiber-optic sync module, 1 m cable, for UR2-H rack pairing
• 6ES7960-1AB04-0XA0: H-Sync fiber-optic sync module, 2 m cable
• 6ES7960-1AC04-0XA0: H-Sync fiber-optic sync module, 5 m cable
• 6ES7960-1AD04-0XA0: H-Sync fiber-optic sync module, 10 m cable, extended rack separation

Power Supply Modules (compatible with S7-400H racks)

• 6ES7407-0DA02-0AA0: PS 407 4A power supply, 24 VDC output, 4 A, for UR2-H rack
• 6ES7407-0KA02-0AA0: PS 407 10A power supply, 24 VDC, 10 A, redundant-capable
• 6ES7407-0RA02-0AA0: PS 407 20A power supply, 24 VDC, 20 A, high-load installations

Interface / Communication Modules

• 6GK7443-1EX30-0XE0: CP 443-1 Ethernet communication processor, TCP/IP, ISO, PROFINET
• 6GK7443-5DX05-0XE0: CP 443-5 Extended PROFIBUS DP master/slave communication processor
• 6ES7460-1BA01-0AB0: IM 460-1 send interface module for distributed I/O expansion
• 6ES7461-1BA01-0AA0: IM 461-1 receive interface module, paired with IM 460-1

Quality Control for the SIMATIC S7-400H Range

S7-400H modules present specific test challenges due to their redundant backplane architecture and H-Sync protocol dependency. Standard PLC bench testing is insufficient to validate redundant CPU behavior. DriveKNMS applies the following test protocol to all S7-400H units prior to dispatch:

• Dual-rack functional test: Each CPU pair is installed in a matched UR2-H rack set and powered simultaneously. H-Sync link establishment, synchronization state (SYNCUP), and switchover behavior are verified under simulated fault conditions.
• PROFIBUS DP / PROFINET IO scan: Communication ports are tested against a reference I/O configuration to confirm master/slave negotiation and cycle time compliance.
• Memory integrity check: Work memory and load memory are tested for bit-error-rate compliance using a full write-read-verify cycle across the addressable range.
• Firmware version logging: Each unit's firmware version is recorded and cross-referenced against Siemens compatibility matrices to flag any known firmware-related field issues.
• Thermal burn-in: Units are operated at rated load for a minimum of 48 hours in a controlled thermal environment prior to final inspection.