Siemens 6ES7315-2EH13-0AB0 Replacement Solution for S7-300

Product Overview

Siemens 6ES7315-2EH13-0AB0 Replacement Solution for S7-300: Smooth Migration & Legacy System Upgrade

The Siemens 6ES7315-2EH13-0AB0 is a CPU 315-2 DP processor module belonging to the SIMATIC S7-300 programmable logic controller family. As Siemens progressively phases out legacy S7-300 hardware in favor of the S7-1500 platform, many plant operators and system integrators face the challenge of sourcing reliable replacement units to sustain production continuity without committing to a full control-system overhaul. TOPNLMS maintains verified stock of the 6ES7315-2EH13-0AB0 to support exactly this need — providing a direct, drop-in replacement that preserves your existing wiring, rack layout, and STEP 7 program logic.

The CPU 315-2 DP integrates a PROFIBUS DP master/slave interface alongside the standard MPI port, making it a central node in distributed I/O architectures. Plants running legacy ET 200M remote I/O stations, IM 153-x interface modules, or third-party PROFIBUS field devices can swap a failed or end-of-life 6ES7315-2EH13-0AB0 without reconfiguring the network topology or rewriting DP slave parameters. The module slots directly into any S7-300 standard rail alongside existing SM 321/SM 322 digital I/O modules, SM 331/SM 332 analog I/O modules, and CP 342-5 communication processors — no mechanical adaptation required.

Compatibility Comparison Table

Seamless Upgrade Solutions

A successful migration around the 6ES7315-2EH13-0AB0 rarely involves the CPU alone. In most S7-300 control cabinets, the CPU shares the rack with a PS 307 10A power supply module that steps down 120/230 V AC to the 24 V DC bus — verifying its output capacity before replacement prevents nuisance trips during commissioning. Distributed I/O is typically handled through ET 200M stations equipped with IM 153-2 interface modules, which communicate with the CPU over PROFIBUS DP; these interface modules are retained unchanged when swapping the CPU, provided the DP address assignments in the hardware configuration remain identical.

For plants that also need to refresh their HMI layer, the existing SIMATIC TP 177B or OP 177B operator panels connect via MPI and continue to function without driver changes after the CPU swap. Where Ethernet connectivity is required for SCADA integration or remote diagnostics, a CP 343-1 Ethernet communication processor installed in the same rack provides ISO-on-TCP and S7 communication without modifying the CPU’s PROFIBUS configuration. Signal conditioning between legacy 4–20 mA field instruments and the S7-300 analog input cards is handled by SM 331 8AI modules, which remain fully compatible and do not require recalibration after the CPU replacement.

When the migration scope extends to the field level, PROFIBUS DP/PA segment couplers and DP/PA link modules preserve connectivity to process instrumentation without rewiring. For applications where the 6ES7315-2EH13-0AB0 is being used as a stepping stone toward an eventual S7-1500 migration, the CPU 1515-2 PN with a CM 1542-5 PROFIBUS communication module provides a forward-compatible upgrade path that retains the existing PROFIBUS DP field network while adding PROFINET capability for new I/O stations. Additionally, where cabinet space is constrained, the compact SM 374 simulation module and DM 370 dummy module can be used to maintain rack slot integrity during phased hardware transitions.

Retrofit Guidance FAQ

Q: Can I reuse my existing STEP 7 project without modification?
Yes. The 6ES7315-2EH13-0AB0 is a direct hardware replacement. Upload your archived STEP 7 project to the new CPU via the Micro Memory Card (MMC). Ensure the MMC is formatted and the project compiled for the correct CPU order number before transfer. No OB, FC, FB, or DB changes are required for a like-for-like swap.

Q: Will the PROFIBUS DP network require reconfiguration?
No. The DP master configuration, slave addresses, and GSD file assignments are stored on the MMC and restored automatically on startup. Field devices including ET 200M stations, drives with PROFIBUS adapters, and third-party slaves will re-establish communication without manual intervention.

Q: Is the wiring to the MPI/DP sub-D connector compatible?
Yes. The 9-pin sub-D connector pinout for both MPI and PROFIBUS DP is standardized across all S7-300 CPU variants. Existing bus connectors and cables are reused without modification.

Q: What about physical installation space?
The 6ES7315-2EH13-0AB0 occupies a standard S7-300 slot width on the UR1 or UR2 rail. No additional DIN rail space or cabinet modification is required. The module height and depth are identical to all S7-300 CPUs, ensuring compatibility with existing cable ducts and door clearances.

Q: How do I handle the battery and real-time clock?
The CPU 315-2 DP uses an internal backup battery (order ref. 6ES7971-1AA00-0AA0) to retain RAM data and the real-time clock during power loss. Replace the battery before commissioning if the unit has been in storage. Set the real-time clock via STEP 7 online functions after first power-up.

Q: What programming cable is needed for initial setup?
Use a PC Adapter USB A2 (6ES7972-0CB20-0XA0) or an MPI/PROFIBUS-compatible programming cable to connect a laptop running STEP 7 V5.x to the CPU’s MPI port. TIA Portal can also be used in offline mode for project preparation before transfer via MMC.

Warranty Assurance

Every 6ES7315-2EH13-0AB0 unit shipped by TOPNLMS is covered by a 12-month warranty from the date of delivery. Prior to dispatch, each module undergoes functional verification including power-on self-test, communication port integrity check, and firmware version confirmation. Units are packed in anti-static ESD bags with foam cushioning to prevent transit damage.

In the event of a confirmed defect within the warranty period, TOPNLMS provides a replacement unit or full refund — whichever the customer prefers — with no return shipping cost to the buyer. Our technical support team responds to after-sales inquiries within one business day. For urgent production-down situations, expedited shipping options are available to minimize plant downtime. Stock is maintained in Xiamen, China, with DHL Express, FedEx International Priority, and UPS Worldwide Expedited available for global delivery.

Procurement teams can request a proforma invoice, packing list, and certificate of conformity for each order. All units are traceable by serial number and batch record. TOPNLMS has supplied S7-300 replacement modules to customers in manufacturing, petrochemical, water treatment, and building automation sectors across Asia, Europe, and the Middle East.