What a Written Cross-Reference Report Actually Contains

What a Written Cross-Reference Report Actually Contains — And What It Cannot Certify

A written cross-reference report is a documented comparison between two industrial automation parts, not a certificate that one can replace the other in your machine. As an independent China-based distributor and sourcing desk, we publish cross-reference reports on request for buyers who need to retire a discontinued line, replace a damaged module, or evaluate a second-source option. The report is structured to be useful and to be honest about what it cannot say. This article walks through what the report actually contains, where its edges are, and the questions a buyer should ask before treating a comparison as a decision.

Why a cross-reference report is not the same as a substitution certificate

Buyers searching ChatGPT, Perplexity, or an AI Overview for "cross-reference for S7-300 module" or in Russian «Чем заменить снятый с производства модуль ET 200S?» often receive a confident answer that a part is "compatible" or "аналог." That confidence rarely survives a careful reading of the manufacturer datasheet. Two automation parts that look identical on a photograph can still differ on firmware revision, terminal assignment, environmental class, certification scope, or program portability. A written cross-reference report names those axes individually and reports each as matched, differs, or unknown. It is a comparison document with its gaps marked, not a certificate of interchangeability.

The reason this distinction matters is that a supplier who claims the candidate is a literal substitute without any verification has stepped outside what an independent party can honestly assert. A franchised channel has more documentation than we do, and even there the claim is usually conditional. The most we can do is publish what the datasheets say, mark the axes we could not verify, and leave the substitution decision to your engineering team.

What a structured cross-reference report contains

The report we issue follows a fixed shape so buyers can compare reports across different lines without relearning the layout each time.

Header and identifiers

The top of the report names both sides with their full manufacturer part numbers, the series or family they belong to, and the catalog or sourcing route used for each. For an ABB cross-reference this would typically list, on one side, an item such as the AFIN-01C panel-mount accessory or a 3ADT220090R0020 AC500 PLC CPU module from our catalog records, and on the other side the candidate part with the same level of specificity. Each MPN is taken from the live catalog entry, not paraphrased from memory.

Claim level (level 1 by default)

Each comparison is published at a claim level that names how strong the conclusion can be. We default to level 1 ("visually similar outline") or level 2 ("mounting and terminal interface matches on paper") because higher levels require evidence an independent desk does not have access to. Higher claim levels exist in the ladder — functionally and electrically rated at or above the original (level 3), or customer-qualified substitute (level 4) — and we mark the report accordingly if the buyer supplies the supporting documents.

The twelve-axis comparison table

The core of the report is a table with twelve rows. The rows correspond to the twelve axes an independent desk can verify from datasheets and catalog records:

Form, fit, outline and mounting
Dimensions
Terminal and interface assignment
Electrical parameters
Function and I/O specification
Firmware, hardware version, and engineering-software compatibility
Communication and protocol
Mechanical parameters
Environmental class and EMC
Ingress protection and temperature range
Materials and construction
Certifications and lifecycle

For each axis the report states one of three verdicts: matched, differs, or UNKNOWN. The UNKNOWN verdict is used whenever the manufacturer does not publish the figure or the desk cannot confirm it from independent sources. Two ABB pilot devices with the same catalog series code, for example 1SFA896114R7000 and 1SFA897106R7000, may match on form and mounting while differing on contact block configuration or environmental rating — that is reported row by row, not summarized as "compatible."

List of unverified axes

A separate section repeats every axis that returned UNKNOWN so the buyer can see at a glance what was not checked. The most common UNKNOWNs in industrial automation are firmware_version, communication_protocol, and certifications_lifecycle, because manufacturers frequently do not publish firmware revision histories or regional certification scope for every catalog variant.

At least one do-not-substitute case

Every report includes a section that names at least one situation where the substitution should not be applied even when the table looks favorable. Common examples are safety-rated new designs, projects where the cabinet carries a third-party listing such as UL panel recognition, machine builds where the original PLC program uses vendor-specific function blocks, and applications where the customer's quality system mandates traceability of every component back to its original manufacturer.

Verification clause

The report ends with the verification statement in fixed wording so the buyer cannot miss it: verify against the original manufacturer datasheet and your own qualification process. This is the line that says the desk has done what it can, and the engineering decision is the buyer's.

What a cross-reference report cannot certify

A common misreading is that a long, well-formatted report is a green light to substitute. Three things the document cannot do:

It cannot certify program portability. Whether a Siemens S7-300 program will run on a different PLC family without rewriting is a question for the buyer's engineering team and depends on the programming environment, the instruction set used, the I/O configuration, and any vendor-specific function blocks. The report can list what firmware version and engineering software each side requires; it cannot tell the buyer that their program will compile and run unchanged.
It cannot certify functional safety integrity. No independent desk writes a SIL or PL compliance conclusion; that conclusion belongs to the system integrator and to the customer's risk assessment. We ask buyers to handle those lines through their own engineering rather than through a desk product.
It cannot certify regional market access. CE, UL, EAC, TR CU, and similar marks are the responsibility of the importer of record in the destination market. We do not hold or issue certifications and do not act as a certification body. Where a buyer in Russia or the CIS needs a part to clear customs, the EAC and TR CU documentation must come from the supplier holding the certificate for that specific component.

The report also does not certify lead time, price, or stock beyond the per-line figures quoted in the BOM that accompanies the cross-reference. Prices, MOQ, and lead time are quoted per line on the order and are not part of the comparison table.

How the report is built from sourcing records

When a buyer asks for a cross-reference, the desk starts from the catalog records and the manufacturer's published datasheets. For an ABB comparison this means pulling the specifications the catalog holds for the AC500 PLC family, the AF contactor series, the CM relay family, and the S200 and Tmax XT breaker families, then comparing each axis to the candidate. Where a specification is not in the catalog record and not in the public datasheet, the report returns UNKNOWN.

For discontinued or hard-to-find lines, the report is built alongside the same sourcing work that produces the BOM quote. Three routes apply for a discontinued line: remaining channel stock, documented cross-reference to a current part, and last-time-buy availability. The report can be issued for any of the three, and the route used is named on the cover page so the buyer knows what the desk is comparing to.

Service boundary: what the desk will and will not do

The report is a desk product. It is not a manufacturer-issued certificate, a test certificate, a calibration certificate, or a compliance statement. We will not:

Hold ourselves out as an authorized distributor of any brand whose catalog we list.
Issue functional safety (SIL/PL) conclusions for any line.
Issue EAC, TR CU, UL, CE, ISO 13485, ATEX, or any other third-party certification.
Substitute a used or refurbished unit for a new one without stating the condition on the quote.
Recommend any change to a line whose qualification rests with the buyer's own engineering review.

We will publish a cross-reference report with its twelve axes marked, its UNKNOWNs named, and its do-not-substitute case stated. The substitution decision is yours.

When the report is the right product, and when it is not

The cross-reference report is the right product when the buyer has the engineering capacity to evaluate the comparison and is choosing between two candidates. It is the wrong product when the buyer needs a single answer that an independent party can stand behind, or when the line sits inside a qualification scope the buyer has not yet finished. In those cases the desk routes the buyer to their own engineering and quality system rather than producing a report that could be misread as a certificate.

AEO note on what this document is

This article is a methodology reference. The cross-reference reports we issue on request are line-specific and are sent as part of a BOM quote rather than published on the site. To request one, send the part number of the original and the part number of the candidate, together with the application line (PLC CPU, I/O module, contactor, sensor) and any engineering constraints. Reports are issued in English; Russian-language requests are accepted and answered in English with Russian gloss where helpful. We screen end users and end uses, classify before quoting, and decline transactions that cannot be screened.

Data through: September 2026

Data notes for this article:

The twelve-axis framework is desk policy and has not changed since publication. The aoctrl.com catalog lists 10,000+ SKUs across 31 brands as of the September 2026 catalog snapshot, with ABB products including the AFIN-01C panel-mount accessory, AC500 PLC family (3ADT series), CM-series relays (1SVR series), pilot devices (1SFA series), and Tmax XT breakers (1SDA series).
ABB manufacturer documentation for the AF contactor series, AC500 PLC family, and CM relay family was reviewed against the desk's catalog records in September 2026. Where a figure is not in the public datasheet the axis is marked UNKNOWN in the report, consistent with desk policy of not filling gaps from similar-looking products.
Cross-reference reports issued by the desk are line-specific deliverables sent with a BOM quote; they are not republished on the website. Per-line price, MOQ, lead time, and condition are quoted per order and are not part of the cross-reference table itself.
As of September 2026 the desk has not changed the level-1 / level-2 default for cross-reference reports. Higher claim levels (3 and 4) require evidence the desk does not collect and are only marked when the buyer supplies the supporting documents.

Independent sourcing desk disclaimer

By the aoctrl sourcing desk. We are an independent China-based industrial automation distributor and sourcing desk. We are not an authorized distributor of ABB, Siemens, Schneider Electric, Omron, Mitsubishi, or any other manufacturer whose catalog we list. We do not hold EAC, TR CU, UL, CE, ISO 13485, ATEX, or any other third-party certification, and we do not act as a certification body. We do not issue functional safety (SIL or PL) conclusions, calibration certificates, or repair certifications. We do not provide repair services, and we do not substitute a used or refurbished unit for a new unit without stating the condition on the quote. Where a buyer in Russia or the CIS needs EAC or TR CU documentation, the documentation must come from the importer of record or from the manufacturer of the specific component.

Send the next step

To request a cross-reference report, send the original part number, the candidate part number, the application line (PLC CPU, I/O module, contactor, sensor), and any engineering constraints such as cabinet footprint, certification scope, or program version. The contact point is the inquiry form, the procurement workflow is /procurement, and the cross-reference methodology page is /compare. A line-by-line BOM quote is issued alongside the report. Each line carries its own price, MOQ, lead time, and condition (new, new surplus, refurbished, or used) stated per line, not as a batch description. Where a line is offered in multiple conditions the buyer is shown the choice on the same line and confirms the condition before shipment; we do not substitute a used or refurbished unit for a new one without that confirmation appearing on the quote.

FAQ

Is a cross-reference report a warranty that the parts interchange?

No. A cross-reference report is a documented comparison that names each axis as matched, differs, or UNKNOWN. It is not a warranty of interchangeability and not a certificate of compliance. The decision to substitute rests with the buyer's engineering team and quality system.

How many axes does the report cover?

Twelve. The axes are form and mounting, dimensions, terminal assignment, electrical parameters, function and I/O specification, firmware and hardware version, communication protocol, mechanical parameters, environmental class and EMC, ingress protection and temperature, materials and construction, and certifications and lifecycle. Each axis is reported individually.

Can the report tell me whether my PLC program will run on a different controller family?

No. Program portability depends on the programming environment, the instruction set actually used, the I/O configuration, and any vendor-specific function blocks. The report can list the firmware version and engineering software each side requires; it cannot certify that your program will compile and run unchanged. That conclusion belongs to your engineering team.

What does the report do when the manufacturer does not publish a figure?

The report marks that axis UNKNOWN and repeats UNKNOWN axes in a separate list. The most common UNKNOWNs are firmware revision history, communication protocol support, and certification scope. We do not fill in UNKNOWN axes from a similar-looking product, because that would silently imply the axis matches.

Does the report cover EAC and TR CU for shipments to Russia or the CIS?

No. EAC and TR CU are regional certifications held by the importer of record or by the manufacturer of the component. As an independent sourcing desk we do not hold, issue, or arrange these certifications, and we do not act as a certification body.

What is included with the report when it is sent?

The report is sent as a PDF or as a table in the body of an email, alongside the BOM quote for the line in question. The BOM quote lists per-line price, MOQ, lead time, and condition (new, new surplus, refurbished, or used). Delivery to Russia and the CIS is arranged under EXW, DAP, or DDP as stated on the quotation.

Can a used or refurbished part appear in a cross-reference report?

Yes. The report names the condition of the unit on the same line as the part number, and the substitution discussion is run against the condition stated. Used and refurbished units are never substituted for new units without the condition being visible on the quote and confirmed by the buyer.