ACFM Buying Guide: Match Instrument, Probe and Reporting Scope
An ACFM instrument and a case of probes are not a complete purchasing specification. Define the material, geometry, intended result and reporting workflow, then confirm that the quoted model and probe arrangement support them together.
For: U.S. NDT equipment coordinators, quality staff and inspection business owners
Describe the surface-crack question precisely
Alternating current field measurement, or ACFM, is used in configured applications for detecting and sizing surface-breaking cracks. The buying question should identify the component, material, access, surface condition and required result. A request that merely says crack detector leaves too much room for a proposal that addresses a different task. Ask the technical owner to define the accepted application and the evidence needed to establish it.
Separate detection, location, length reporting and depth reporting in the requirements. A demonstration of one does not automatically establish all of the others for every condition. This guide concerns equipment selection and records. It does not prescribe scanning technique, probe frequency, defect acceptance limits or sizing procedures. Those are controlled by the applicable technical requirements and authorized personnel. Purchasing supports that process by obtaining a clearly bounded configuration and usable evidence.
Identify the instrument variant on the quotation
Eddyfi's Amigo2 comparison distinguishes the Amigo2 and Amigo2 SE variants; the listed SE scope is limited to single-element probes. That is a concrete example of why a family name is insufficient. If the planned service requires an array, the buyer must confirm the exact model and supported options rather than assuming every instrument carrying the same family name accepts the same probe functions.
Record the offered model designation, installed options and software configuration. Ask the supplier to identify any upgrade path separately, including whether it is currently available and what it requires. A possible future upgrade should not be counted as delivered capability. If the demonstration uses a different variant, resolve that difference before comparing its results with the quotation. The acceptance record should identify what the organization actually receives and can use within its approved application scope.
Map each probe to an intended component feature
Create a probe-to-task matrix. Each row should name the component feature, material, access constraint, required output, proposed probe and supporting evidence. The ACFM probe catalog includes different body styles and application considerations such as geometry and access. Use that variety as a prompt to obtain a specific response, rather than treating all probes in a kit as interchangeable surface sensors.
Have the technical owner review the proposed mapping. A probe that physically reaches a location may still need application evidence for the intended result. Conversely, a probe demonstrated on an open specimen may not have the access needed on the actual component. Preserve the relevant drawings or representative photographs supplied for review. When the supplier proposes an alternative body style, document the reason and verify that the replacement is included in both the trial and final quotation.
Compare single-element and array packages by the real task
Ask what an array changes in the proposed workflow and what supporting hardware or software it requires. Do not reduce the comparison to the number of sensing elements. The technical owner should evaluate the required coverage and interpretation, while purchasing records the configured capability and the work needed to produce an accepted report. A broader nominal sensing arrangement is not a universal guarantee of complete coverage on every geometry.
Request a representative demonstration of the task using each serious candidate configuration. Record the areas examined, access limitations, location information and retained evidence. Include review effort and any additional passes or follow-up required by the approved plan. The resulting comparison should explain why one configuration is useful for the organization's workload. It should not imply that a faster demonstration on one favorable specimen establishes superiority across all components or replaces application-specific technical review.
Treat coating claims as application-specific
A through-coating capability can reduce disruption in a suitable application, but a generic statement about coatings does not settle every surface condition. Identify the coating type and other relevant information available for the intended work, then request a documented supplier response. The technical owner determines what evidence is needed. Purchasing should preserve the response and any exclusions instead of promising universal inspection through any coating before the application has been reviewed.
Ask whether the quoted probe and software arrangement is the one used in the supporting evidence. A special application variant should appear explicitly in the equipment list. If the supplier's documentation concerns a different material or coating condition, mark it as background information rather than direct proof for the proposed task. The purchase decision can include a staged trial or a limited initial scope. What matters is that the boundary remains visible in the accepted service description.
Keep legacy compatibility tied to its configuration data
The Amigo2 product page describes support for certain legacy probes through their relevant configuration files. Compatibility therefore involves more than a connector. If the organization wants to reuse existing probes, provide their exact identities and ask the supplier what records, files and review are required. Do not assume that a physically connected legacy probe is ready for every application supported by a newer probe family.
Build a legacy-probe reconciliation list showing identity, available documentation, required configuration file, supported instrument and application disposition. Preserve the original evidence and the supplier's response. If a necessary file is missing or its identity is uncertain, treat that as an unresolved item rather than substituting a similarly named file. The technical owner should approve the resulting configuration. Purchasing can then distinguish genuinely reusable assets from items that require further work or should remain outside the new package.
Clarify where probe information is stored
Eddyfi describes newer probe families with probe information stored in probe memory. Ask which information the proposed software reads automatically and which remains a user responsibility. Do not assume that automatic recognition confirms every application setting or validates the intended material. The buyer should understand the record relationship without trying to replace the technical setup process.
Demonstrate connecting the intended probes and opening their saved projects in a controlled trial. Ask the reviewer to identify the probe used and the relevant configuration from the retained evidence. If probe metadata are visible during acquisition but absent from an export, determine whether the customer or internal reviewer needs them elsewhere. Record the supported handover. The objective is a reliable association between the physical probe and the examination record, including when several probes are used during the same job.
Specify the record behind a reported size
Ask what evidence accompanies a reported crack length or depth in the proposed workflow. The technical owner determines which signals, location references, configuration information and review notes must be retained. Purchasing should ensure the system can save and deliver that package. A summary table of sizes may be convenient, but it should not be assumed to contain everything needed for a later technical review.
Request a sample project and its final report. Have an authorized reviewer trace a selected result back to the relevant recorded evidence. Identify which information is inherent in the project and which is entered manually. If the report includes an interpretation or disposition, preserve its relationship to the measured or estimated quantity. The procurement exercise should make the chain understandable without implying that the software's ability to calculate or display a value establishes its suitability for every application.
Plan physical location references before the demonstration
Define how the customer expects a reported indication to be located on the component. This may involve a weld identifier, drawing reference, coordinate convention and supporting images. The technical owner selects the appropriate approach. Ask the supplier to show how the proposed system records and exports that information, including any encoder or annotation functions included in the quote.
Use fictional component identifiers with several similar features during the trial. Ask another reviewer to find the reported location using only the delivered package. A result that depends on the original operator pointing to the component is not a complete demonstration of the intended record handover. Document any manual steps needed to associate photographs, notes and data. Include those steps in the workload estimate so the package is evaluated by the final usable evidence rather than the acquisition screen alone.
Distinguish topside and underwater configurations
The manufacturer's catalog separates topside and underwater probe arrangements. It also describes configurations where a probe is used underwater while the instrument remains dry. Do not transfer a probe's environmental statement to the complete instrument, connector or cable arrangement. Ask for the documented scope of the exact system proposed for the intended environment and have the responsible site and technical owners review it.
If an organization expects to serve both environments, keep the two configurations distinct in the purchasing matrix. Identify the required probes, cables, interfaces, documentation and support items for each. A common software family does not make every physical component suitable for both roles. This guide does not authorize underwater deployment or provide handling instructions. It helps the buyer ensure that a broad commercial description is replaced by a complete, reviewable configuration statement before the equipment is committed to a job.
Evaluate remote review as a separate function
A connected instrument may support file transfer, screen sharing or other collaboration features. Ask which function the proposed workflow actually needs. Viewing a live screen, reviewing saved data and controlling an examination are different capabilities with different dependencies. Do not assume one feature establishes all of them. Obtain the current supported software and account requirements for the quoted version.
Test the intended handover using approved nonproduction records. The remote reviewer should receive the information needed for the assigned role and understand whether the record is provisional or final. Record any dependency on internet access, cloud storage or a particular software license. If the organization must work offline, demonstrate that workflow explicitly. The purchasing requirement should describe the supported review path, including its limitations, rather than treating connectivity as a substitute for a defined evidence package.
Work through a fictional array-compatibility mismatch
A hypothetical inspection company already owns single-element ACFM probes and plans to add an array for a new component family. Its initial quotation names a product family but omits the instrument variant. The demonstration uses an array-capable configuration. During review, the buyer asks for the exact model and discovers that the lower-priced offer does not include the intended array capability. The team requests a corrected quotation before using the demonstration result in its business case.
The technical owner separately evaluates the proposed array application and the compatibility of the existing probes. The final matrix identifies which probes can be reused, which require configuration records and which new items are needed. This fictional example is not a claim about a supplier's sales practice. It illustrates how model identity, legacy compatibility and application evidence are distinct purchasing questions that can otherwise be hidden under one familiar technology name.
Include reporting time and access rights in the cost
Ask the supplier to demonstrate the complete path from a saved examination to the required report and archive. Record manual annotation, review and export steps. A short acquisition demonstration does not establish the total effort needed to deliver a customer-ready package. If a specialist prepares the demonstration report using additional software, identify whether that capability is included and available to the organization's own reviewers.
Confirm the number and type of software rights needed for acquisition, analysis and retained-record access. Ask what remains available after a subscription or support arrangement ends, if applicable. Preserve the answer in the commercial record. A lower initial price may leave a different continuing obligation for review access. Compare the supported total workflow under the organization's actual assumptions instead of treating every proposal with a display and export button as commercially equivalent.
Receive the package against a configuration matrix
At delivery, reconcile the instrument variant, probes, cables, encoders where included, software and supporting evidence. Check the actual identities and option scope against the accepted offer. Record deviations and assign a disposition owner. Do not quietly substitute a probe from another kit to make the shipment appear complete unless the appropriate technical review establishes that substitution as acceptable for the intended role.
Retain the final probe-to-task matrix with the application evidence and example report. NDT Connect can coordinate equipment identities, status, due dates and notes; it does not interpret ACFM signals, calculate crack sizes or store examination datasets. Keep the technical records in the selected inspection system. The procurement file should make it possible for a future coordinator to identify the supported configuration without relying on the person who attended the original demonstration.
Preserve exclusions when the service expands
Review the application statement when the organization proposes a materially different component, material, coating or environment. The availability of unused probes in the case does not establish an approved service for that new task. Record the additional question and obtain the necessary technical and supplier evidence. This allows useful expansion while keeping the original acceptance record intact.
Maintain a concise list of unresolved or excluded applications alongside the accepted scope. That list helps sales and scheduling staff avoid promising a capability simply because the equipment appears capable in a general brochure. Update it when evidence supports a change, with the responsible owner's decision recorded in the controlled file. The equipment purchase then remains connected to a defensible service description as the organization's workload evolves.
Frequently Asked Questions
Does every model in an ACFM instrument family support arrays?
No. Verify the exact model and installed capability; the cited Amigo2 comparison distinguishes the single-element-only SE variant.
Can legacy probes be reused solely because the connector fits?
No. Confirm the supported instrument, required configuration data and application evidence for each probe.
Does an underwater probe rating cover the whole system?
No. Obtain the documented environmental scope for the complete proposed instrument, probe, cable and connector arrangement.
References & Standards Cited
- Eddyfi: Amigo2 model and probe support comparison View source ↗
- Eddyfi: Sensu 2 topside ACFM probes View source ↗
- Eddyfi: ACFM probe catalog View source ↗
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