Transformer FAT witness and hold points should define who must be notified, who may stop or release work, and what evidence allows the next activity to begin. Agree these controls in the inspection and test plan (ITP) before fixing attendance dates. Include absence and waiver rules, corrective action and retesting, report approval, and permission to ship. “FAT included” does not settle those decisions. Cover: concept illustration of planning documents beside a transformer, not a photograph or record of an actual HEAKOR factory test.
This guide is for EPC procurement and quality teams buying liquid-immersed substation transformers for IEC-based industrial projects. It addresses the contractual release process, not a test procedure or a universal list of mandatory witness activities.
Define witness, hold and review points in the project ITP
The ITP legend should explain the consequence of each control point, not just assign a letter. A witness point can allow work to proceed after valid notice if the buyer does not attend; a hold point prevents further work until the specified release condition is satisfied. These meanings must be confirmed in the project documents.
For example, the City of San Marcos's 2019 transformer procurement distinguishes a witness point that permits continuation after nonattendance from a hold point requiring inspection, witnessing or prior written authorization. This is a specific U.S. purchaser's arrangement in section 19000.1.4, not an IEC rule for every project.
Define document-review points separately: is a report submitted for information, review or approval before another activity? Also distinguish the test category from attendance. Witnessing describes an observation arrangement; it does not turn a routine test into a type test or establish compliance by itself.
Use a control-point matrix to agree when work can continue
For each point, record the trigger, accountable role, decision evidence and continuation rule. The following is a buyer's planning framework, not a completed or approved ITP. Add the actual activities, acceptance criteria, named contacts and agreed deadlines for your order.
| Control point | Trigger and timing to agree | Decision owner and record | Condition for continuing |
|---|---|---|---|
| Readiness for notice | Required drawings, test schedule and procedures reach the agreed status. | Supplier QA issues the readiness package; buyer identifies any prerequisite approval. | Formal notice meets the agreed readiness conditions. |
| Witness activity | Notice identifies the activity, location, date, time zone and required lead time. | Named buyer coordinator confirms attendance or waiver; retain the notice. | Apply the explicit nonattendance rule, not an assumed permission. |
| Hold activity | Activity reaches the designated stop; specify the release-response deadline. | Authorized release role records inspection acceptance or the permitted written waiver. | Do not pass the hold point without the required release. |
| Deviation and retest | Record a nonconformance, interrupted test or change affecting results. | Responsible engineer approves disposition; QA records corrections and retest scope. | Complete the approved actions and renew notice where required. |
| Report review | Submit the agreed report package by its separate deadline. | Named technical reviewer records acceptance, comments or rejection. | Achieve the document status required for the next milestone. |
| Shipment release | Required results, documents and open-item dispositions are available. | Named dispatch-release authority issues the specified release record. | Ship only when the order's release conditions are met. |
Make the notice usable before anyone books travel
Define when the notice period starts and what makes a notice valid. State whether the interval uses calendar or working days, how receipt is acknowledged, and whether changed dates or incomplete prerequisites require a new notice. Do not turn one purchaser's lead time into a general transformer requirement.
Include the factory location, proposed sequence and duration, activities to be witnessed, pre-read documents, contact details and attendance method. Identify the documents that must already be approved. For a remote session, agree the viewing and communication arrangements and what happens if the connection fails. Remote attendance is not automatically an acceptable substitute for an on-site witness requirement.
Separate nonattendance, waiver and hold-point release
A missing witness is not the same as an authorized waiver. Before testing, resolve whether valid notice alone permits continuation at that particular point. If the documents are silent or inconsistent, obtain the designated party's decision rather than treating silence as consent.
Record a waiver against the specific activity and date, with any conditions. Identify whether the person attending may only observe, may release a hold point, or may approve a technical deviation. Do not assume an inspector can exercise all three powers. Waiving attendance should not be recorded as waiving the test or its acceptance criteria.
Agree corrective action and retesting before a problem occurs
The retest decision should follow the documented issue and authorized engineering disposition. Record what happened, the affected activity, the proposed correction and the reason for repeating or extending tests. Do not substitute an informal “retest passed” message for the required review.
Specify who decides which results remain usable, which activities must be repeated, and whether another witness notice or hold-point release is required. Keep the original outcome and approved disposition with the subsequent evidence. A scheduling coordinator should not silently narrow the retest scope to preserve a shipping date.
Keep report approval and shipment release distinct
Attendance records, technical approval and permission to dispatch answer different questions. In its December 2020 General Technical Requirements, POWERGRID separately requires approval of specified test results and written dispatch clearance. Its clauses also address reporting and completion certification. These are purchaser-specific provisions, particularly sections 8.3.5 and 8.3.12, not universal FAT milestones.
For your order, identify which open items block shipment and whether any may remain open under a written disposition. Define submission, review and resubmission deadlines separately. Reports also need to belong to the correct supplied equipment; the transformer test report traceability guide covers that separate check.
Where this framework stops
The project specification and approved engineering documents govern the actual test scope and acceptance limits. IEC 60076-1:2011 addresses power transformers within its stated scope; its public catalogue description is not an ITP or an attendance agreement. Factory release also does not establish site readiness or permission to energize. POWERGRID's quality-assurance policy, for example, distinguishes manufacturing inspection plans from field quality plans.
Frequently asked questions
Does every routine test need a buyer's witness?
Do not assume so. Agree the tests to be performed and the attendance points separately, following the applicable specification and order. A test can remain required even when buyer attendance is waived.
Can one inspection agency release every hold point?
Only if its documented authority covers those releases. Identify any decisions reserved for the buyer, consultant or responsible engineer, and establish an escalation contact before the inspection.
What if the factory changes the FAT date?
Apply the agreed change-notice procedure. Confirm the revised readiness status, notice period and attendance plan rather than assuming the original invitation covers the new date.
Does a signed witness sheet mean final acceptance?
Not by itself. Specify what each signature confirms. Observing an activity, approving its results, releasing shipment and accepting equipment after site checks may be separate decisions.
Can a FAT plan be copied from another transformer order?
Use it only as a starting point. Review the equipment, test scope, contractual definitions, authority, location, notice requirements and release documents for the new order.
Define your FAT requirements with HEAKOR
For a liquid-immersed substation transformer enquiry, include the rating, voltages, frequency, destination, applicable specification, proposed ITP, target dates and required attendance method. List the requested witness and hold points, pre-read documents, authorized roles and report/dispatch conditions. The technical document centre helps organize document requirements.
Submit Your Project Specification to establish the requested quotation scope. Test availability, attendance arrangements, document scope and timing require project-specific confirmation; this guide does not establish that any witness service is included in an offer.