Siemens SIMATIC S7-300 CP 342-5 Modules: 6ES7023-8TP60-Z Z-G91-K80

Technical Dossier

Product Details And Specifications

Siemens SIMATIC S7-300 Series Technical Notes

The Siemens SIMATIC S7-300 is one of the most widely deployed programmable logic controller (PLC) platforms in global heavy industry. Installed across petrochemical refineries, nuclear power auxiliary systems, offshore platforms, chemical processing plants, and large-scale manufacturing facilities, the S7-300 series has maintained a dominant position in distributed control system (DCS) and discrete automation architectures since its commercial introduction in the mid-1990s. The 6ES7023-8TP60-Z Z-G91-K80 is a configurable variant of the CP 342-5 PROFIBUS communication processor module within this platform, equipped with application-specific configuration options encoded in the Z-suffix ordering code (Z-G91-K80), indicating factory-configured firmware or hardware customization for specific fieldbus topologies.

The S7-300 backplane bus architecture supports modular expansion across up to 32 modules per rack segment, with inter-rack communication via IM (Interface Module) pairs. This scalability made the platform the reference standard for mid-range automation in industries where continuous uptime and deterministic scan cycles are non-negotiable operational requirements.

The Evolution of SIMATIC S7-300 Architecture

The S7-300 platform was introduced by Siemens in 1994 as the successor to the S5-115U series, adopting a 32-bit processor architecture and the STEP 7 programming environment (IEC 61131-3 compliant). Early CPU variants such as the CPU 312 and CPU 314 established the modular rail-mount form factor that remains physically compatible with current-generation modules.

The introduction of PROFIBUS-DP as the primary fieldbus protocol in the late 1990s drove the development of the CP 342-5 and CP 343-5 communication processor family, of which the 6ES7023-8TP60-Z is a member. These modules enabled the S7-300 to function as both PROFIBUS master and slave, a critical capability for integration into multi-vendor DCS environments.

By the mid-2000s, Siemens introduced PROFINET-capable CPUs (e.g., CPU 315-2 PN/DP), gradually shifting new installations toward Ethernet-based fieldbus. However, the installed base of PROFIBUS-centric S7-300 systems in legacy plants remained substantial. As of 2023, Siemens has announced the formal end-of-life transition for the S7-300 platform, with the SIMATIC S7-1500 designated as the migration target. This transition does not eliminate the demand for S7-300 spare parts; rather, it intensifies it, as plant operators with 15–25 year asset lifecycles require continued access to replacement modules without full system migration.

Compatibility note: S7-300 modules are not electrically or mechanically interchangeable with S7-400, S7-1200, or S7-1500 series components. Backplane bus pinout, rack rail dimensions, and firmware environments are platform-specific.

SIMATIC S7-300 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly sourced modules within the SIMATIC S7-300 platform. Modules are classified by functional category.

Communication Processors (CP)

6ES7342-5DA02-0XE0: CP 342-5 PROFIBUS-DP master/slave communication processor, 12 Mbit/s.
6ES7342-5DA03-0XE0: CP 342-5 revised firmware revision, enhanced diagnostic buffer capacity.
6ES7343-1EX30-0XE0: CP 343-1 Industrial Ethernet TCP/IP communication processor, 10/100 Mbit/s.
6ES7343-1GX31-0XE0: CP 343-1 Advanced with PROFINET IO controller capability.
6ES7023-8TP60-Z Z-G91-K80: CP 342-5 configurable variant with Z-suffix factory options G91 and K80 for application-specific PROFIBUS topology.
6ES7340-1AH02-0AE0: CP 340 point-to-point RS-232C serial communication module.
6ES7340-1BH02-0AE0: CP 340 point-to-point RS-422/RS-485 serial communication module.

Central Processing Units (CPU)

6ES7314-1AG14-0AB0: CPU 314, 128 KB work memory, MPI/PROFIBUS interface, standard mid-range controller.
6ES7315-2AG10-0AB0: CPU 315-2 DP, integrated PROFIBUS-DP master/slave interface, 256 KB work memory.
6ES7315-2EH14-0AB0: CPU 315-2 PN/DP, integrated PROFINET IO controller and PROFIBUS-DP interface.
6ES7317-2AK14-0AB0: CPU 317-2 DP, 1 MB work memory, high-speed processing for complex automation tasks.
6ES7318-3EL01-0AB0: CPU 319-3 PN/DP, maximum S7-300 performance class, dual PROFINET and PROFIBUS interfaces.

Digital Input/Output Modules (DI/DO)

6ES7321-1BL00-0AA0: SM 321 digital input module, 32 channels, 24 VDC, sink/source compatible.
6ES7322-1BL00-0AA0: SM 322 digital output module, 32 channels, 24 VDC, 0.5 A per channel.
6ES7323-1BL00-0AA0: SM 323 combined DI/DO module, 16 DI + 16 DO, 24 VDC.

Analog Input/Output Modules (AI/AO)

6ES7331-7KF02-0AB0: SM 331 analog input module, 8 channels, configurable ±10 V / 0–20 mA / thermocouple / RTD.
6ES7332-5HF00-0AB0: SM 332 analog output module, 8 channels, ±10 V / 0–20 mA, 12-bit resolution.
6ES7334-0CE01-0AA0: SM 334 combined AI/AO module, 4 AI + 2 AO, 8-bit resolution, cost-optimized variant.

Power Supply Modules (PS)

6ES7307-1BA01-0AA0: PS 307 power supply, 24 VDC / 2 A output, 120/230 VAC input.
6ES7307-1EA01-0AA0: PS 307 power supply, 24 VDC / 5 A output, stabilized, rail-mount.

Sourcing Hard-to-Find & Obsolete SIMATIC S7-300 Parts

For plant operators running S7-300 systems in environments where a full migration to S7-1500 is not feasible within the current maintenance cycle — due to capital expenditure constraints, process continuity requirements, or regulatory approval timelines — DriveKNMS provides multi-year spare parts reservation agreements to guarantee module availability against planned maintenance schedules.

Quality Control for the SIMATIC S7-300 Range

SIMATIC S7-300 modules present specific test challenges due to their backplane bus communication architecture. Unlike standalone devices, CP and SM modules require active rack communication to validate core functionality. DriveKNMS employs a dedicated S7-300 test bench incorporating a live S7-300 rack with CPU, PS, and IM modules, enabling full functional validation under operational conditions.

Test procedures for CP modules such as the 6ES7023-8TP60-Z Z-G91-K80 include: PROFIBUS segment connectivity verification at 9.6 kbit/s through 12 Mbit/s baud rates; master/slave role switching validation; diagnostic buffer read-out via STEP 7 or TIA Portal in S7-300 compatibility mode; and firmware version confirmation against Siemens product lifecycle records. SM analog modules undergo calibration verification against traceable reference standards for both voltage and current measurement channels. All modules are inspected for backplane connector pin integrity, capacitor condition on power rails, and EEPROM data retention prior to dispatch.