SIEMENS 6ES7315-2EH14-0AB0

What is the 6ES7315-2EH14-0AB0 and where is it used?

The 6ES7315-2EH14-0AB0 is a Siemens SIMATIC S7-300 CPU 315-2 PN/DP. It is a central processing unit designed for automation applications where traditional S7-300 architectures, PROFIBUS/MPI and PROFINET connectivity are combined within a single controller. The CPU provides a combined MPI/PROFIBUS DP interface supporting data rates of up to 12 Mbit/s, together with a PROFINET interface featuring an integrated 2-port switch. This makes it particularly suitable for machines and existing installations where decentralised I/O, HMIs, drives and service connections must be integrated reliably. Operation requires a SIMATIC Micro Memory Card (MMC).

Overview of the key technical data and what it means

From a performance perspective, the CPU is positioned in the mid-range of the S7-300 family. It operates from a 24 V DC supply, provides 384 KB of work memory, and uses an MMC of up to 8 MB as removable load memory. In practice, this provides sufficient resources for typical machine and production-line applications, battery-free retentive data storage and a solid foundation for diagnostics and communication tasks. On the communications side, the CPU supports up to 124 PROFIBUS DP nodes and up to 128 PROFINET IO devices. Additional features include an integrated web server, a diagnostic buffer with up to 500 entries, and extensive built-in diagnostic functions. The permitted operating temperature range is 0 to 60 °C.

Product status, life-cycle status and obsolescence

For procurement, maintenance and production management teams, the lifecycle status is particularly important. Siemens officially classifies the 6ES7315-2EH14-0AB0 as a spare part, and the Siemens Industry Mall identifies its lifecycle status as PM410: Product Cancellation, effective from 01 October 2025. The EICHLER product page likewise lists the status as EOP: 2025-10-01. This is a clear indication that active obsolescence management is required: spare-parts inventories should be reviewed, critical replacement components secured, project-specific configurations archived, and repair or replacement strategies defined. In the Siemens product sources reviewed, no officially designated successor was identified for this exact order number. As a result, any migration or replacement strategy should always be assessed on a system-specific basis.

Available EICHLER services and their practical relevance

For operators of older S7-300 installations, the services offered by EICHLER are particularly relevant when downtime must be minimised and existing projects should continue operating without the risks associated with major system modifications. According to the product page, repair, exchange, used equipment and new equipment options are available. Repair is listed with a turnaround time of 2–5 days and includes technical cleaning, preventive maintenance, comprehensive functional testing and a minimum 24-month warranty. An optional test report is also available. Organisations that need to minimise downtime as much as possible may benefit more from an exchange service, whereas those balancing budget constraints and long-term availability may choose used or new equipment. These services are intended exclusively for business customers.

Is the 6ES7315-2EH14-0AB0 still active in the Siemens lifecycle?

No. Siemens no longer classifies the module as an active standard product and instead lists it as a spare part with the lifecycle status PM410: Product Cancellation, effective from 01 October 2025. For operators, this means that the CPU remains technically relevant but its long-term availability should no longer be taken for granted. Anyone using this CPU in a production-critical environment should therefore secure spare-parts stock, repair options and comprehensive documentation of the hardware version, software version and parameterisation.

Does the CPU 315-2 PN/DP require a Micro Memory Card?

Yes. Siemens explicitly states that this CPU requires a SIMATIC Micro Memory Card (MMC) for operation. The MMC functions as the load memory and stores the project data permanently. In practice, the card should only be removed when the power supply is switched off or the CPU is in STOP mode, and only when no write operation is active. A damaged or incorrectly prepared MMC can result in start-up problems, SF alarms or an inconsistent project state.

Can I use PROFIBUS and PROFINET simultaneously with the 6ES7315-2EH14-0AB0?

Yes. This is one of the key strengths of the CPU. The module provides an RS-485 interface for MPI/PROFIBUS DP communication as well as a PROFINET interface with two ports and an integrated switch. On the PROFIBUS side, it supports both master and device functions, while on the PROFINET side it supports features including IO Controller, IO Device, web server functionality and open Ethernet communication. This makes the CPU particularly useful in retrofit projects where existing PROFIBUS networks must remain operational while new devices are integrated via PROFINET.

Which software is required for project engineering, diagnostics and service?

Siemens specifies STEP 7 V5.5 or later for project engineering. In addition, the CPU offers integrated diagnostic functions such as a diagnostic buffer, status and control functions, breakpoints and an integrated web server. For maintenance personnel, this is important because faults can be analysed not only via LED indicators but also through structured diagnostic tools and online diagnostics. In older installations with multiple service providers, these capabilities can significantly reduce the time required to identify the root cause of a fault.

How many devices and IO nodes can the CPU support?

The CPU supports up to 124 PROFIBUS DP devices and up to 128 PROFINET IO devices. It also provides a process image capacity of up to 2,048 bytes of inputs and 2,048 bytes of outputs. For procurement and engineering teams, these figures provide a useful indication of whether the CPU remains sufficient for an existing machine or production cell, or whether future expansion may be limited by communication capacity or system size constraints.

When is repair, exchange, used equipment or new equipment the most appropriate option?

Repair is generally the best choice when the existing CPU should remain part of the installation and a rapid return to operation can be achieved with predictable effort. An exchange unit is often preferable during an unplanned production stoppage when a fully functional replacement is required immediately. Used equipment can be attractive when budget considerations and short-term availability are more important than obtaining a factory-new device. New equipment is typically chosen when maximum assurance regarding stock availability and procurement standards is required. According to the referenced EICHLER product page, all four options are available for this CPU, together with an optional test report, providing additional verification and documentation where required.