Siemens 6ES7390-1AF30-0AA0 | SIMATIC S7-300 Mounting Rail — 530mm Aluminium Profile

Part Number: 6ES7390-1AF30-0AA0

Manufacturer: Siemens AG (Germany)

Product Type: Mounting Rail (Profile Rail) for SIMATIC S7-300

Length: 530 mm

Height: 122 mm

Weight: approx. 713 g 

The S7-300's Mechanical Backbone

The 6ES7390-1AF30-0AA0 is the 530 mm mounting rail for the Siemens SIMATIC S7-300 — the aluminium profile that every S7-300 module snaps onto and screws into. It is not a passive accessory. It is the mechanical structure of the PLC assembly. Modules must be aligned to this rail; the rail must be mounted to the cabinet; the rail must be grounded for the PLC's earth bonding.

Siemens manufactures the S7-300 profile rail in seven standard lengths from 160 mm to 2000 mm. The 530 mm version (6ES7390-1AF30-0AA0) suits medium-sized S7-300 builds — typically a CPU plus four to eight I/O and function modules, which covers a large proportion of real-world installations. When the required assembly length falls between standard sizes, the rail can be cut to any intermediate length in the field using standard metalworking tools.

The surface is galvanically isolated — the aluminium substrate is electrochemically treated to provide a corrosion-resistant, conductively consistent surface for the ground connection. Each module's earth point makes contact with this rail surface, so a corroded or coated rail creates grounding problems.

Key Specifications

FAQ

Q1: Can the 6ES7390-1AF30-0AA0 rail be cut shorter for a tight cabinet installation?

Yes. The S7-300 profile rail is made from aluminium and can be cut to any required length using a hacksaw or cold saw. After cutting, dress the cut edge to remove burrs. Ensure the mounting hole positions still accommodate the required modules. Note that end caps or rail segments shorter than required for the intended module count leave insufficient space for module clips and grounding terminals.

Q2: Is grounding the rail mandatory?

Yes. SIMATIC S7-300 modules bond their chassis ground to the profile rail. Without a proper earth connection from the rail to the cabinet PE bus, the PLC's EMC protection is compromised and module faults caused by ground potential differences become possible. The grounding terminal for the S7-300 rail is a separate order item — confirm it is included in the cabinet build.

Q3: The 6ES7390-1AF30-0AA0 is listed with lifecycle status PM400 from October 2023. What does this mean?

PM400 is Siemens' classification for products being removed from active sales. The rail remains available from stock and the aftermarket but is no longer part of Siemens' active sales program. For new S7-300 installations, Siemens now steers customers toward SIMATIC S7-1500. For existing S7-300 systems, the rail continues to serve as a replacement accessory.

Q4: Can any S7-300 module mount on this rail, regardless of module type?

Yes. The S7-300 profile rail is universal across the entire S7-300 family — CPUs, signal modules, function modules, communication processors, and interface modules all use the same mounting profile. Module position on the rail is determined by slot assignment in STEP 7, not physical rail position (except for the CPU, which must occupy slot 2).

Q5: Where is spare stock of the 6ES7390-1AF30-0AA0 sourced given the PM400 status?

Industrial automation distributors and Siemens-authorised spare parts dealers continue to hold stock. The rail is a high-volume consumable item with no active electronics, so aftermarket supply is typically robust. The part number is consistent — confirm the 530 mm length specifically when ordering, as the different length variants all share the 6ES7390-1AF30 base number.