{"id":3926,"date":"2026-06-19T09:00:00","date_gmt":"2026-06-19T09:00:00","guid":{"rendered":"https:\/\/xbrele.com\/?p=3926"},"modified":"2026-06-09T15:27:00","modified_gmt":"2026-06-09T15:27:00","slug":"vacuum-contactor-fat-sat-acceptance-matrix","status":"publish","type":"post","link":"https:\/\/xbrele.com\/fr\/vacuum-contactor-fat-sat-acceptance-matrix\/","title":{"rendered":"Guide de la matrice de r\u00e9ception FAT\/SAT des contacteurs \u00e0 vide"},"content":{"rendered":"

A vacuum contactor FAT\/SAT acceptance matrix is the structured, line-by-line document that records every verification activity performed on a vacuum contactor — first at the manufacturer’s facility (Factory Acceptance Test) and then at the installation site (Site Acceptance Test) — along with the specific pass\/fail threshold, the responsible party, and the authorized sign-off for each item.<\/p>\n

This guide covers what the matrix must include, how to evaluate supplier submissions, and what a complete handover package requires — from purchase specification through final sign-off.<\/p>\n

\"Overview
A complete FAT\/SAT matrix tracks each verification item from documentation review through final sign-off.<\/figcaption><\/figure>\n
\n

Quick Diagnosis: Common FAT\/SAT Failure Modes<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
Symptom<\/th>\nFirst Test<\/th>\nLikely Root Cause<\/th>\nNext Action<\/th>\n<\/tr>\n<\/thead>\n
Insulation resistance below 100 Mohm at FAT<\/td>\nRe-test after 30-min dry-out at 40 deg C<\/td>\nMoisture ingress or contaminated interrupter<\/td>\nInvestigate gland seals and enclosure integrity; replace interrupter if IR does not recover<\/td>\n<\/tr>\n
Hi-pot leakage current spike<\/td>\nReduce voltage; re-apply slowly<\/td>\nCracked vacuum interrupter or inadequate creepage<\/td>\nReplace interrupter; do not re-test without root-cause resolution<\/td>\n<\/tr>\n
One contact resistance pole 2-5x higher than others<\/td>\nVerify contact spring force with go\/no-go gauge<\/td>\nUneven contact wear, misalignment, or contaminated surface<\/td>\nDisassemble, inspect contact faces, re-test<\/td>\n<\/tr>\n
Contactor fails to close at 85% rated coil voltage<\/td>\nMeasure voltage at coil terminals, not panel supply<\/td>\nUndersized control cable causing voltage drop<\/td>\nReplace control cable to specified cross-section; re-measure<\/td>\n<\/tr>\n
Pole-to-pole operating time asymmetry > 3 ms<\/td>\nCheck mechanism alignment with manufacturer tooling<\/td>\nMechanical binding or worn pivot<\/td>\nRealign mechanism; re-test timing<\/td>\n<\/tr>\n
Audible re-strike after load interruption at SAT<\/td>\nVacuum integrity hi-pot across open contacts<\/td>\nDegraded vacuum in interrupter<\/td>\nReplace interrupter; do not re-energize<\/td>\n<\/tr>\n
B-phase lug temperature 20+ deg C above A and C<\/td>\nMicro-ohmmeter on B-phase termination<\/td>\nUnder-torqued or incorrectly re-made connection<\/td>\nRe-torque to specification; repeat thermographic scan after 30-min run<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n

What the Acceptance Matrix Must Cover<\/h2>\n

At its most precise, the acceptance matrix is a tabular record structured around four columns: the specific test or document item, the acceptance criterion derived from IEC 62271-106 or ANSI\/IEEE C37.66 or the project specification, the actual measured result (not a checkbox), and a dated signature from the inspector or commissioning engineer.<\/p>\n

    \n
  1. Documentation verification — type test certificates, routine test reports, vacuum integrity certificates, and drawing packages matched to the serial number under test.<\/li>\n
  2. Dielectric and insulation tests — power-frequency withstand, partial discharge measurement, and insulation resistance referenced to the rated voltage class and ambient temperature.<\/li>\n<\/ol>\n
    \n

    Documents Required Before Testing Can Begin<\/h2>\n

    Missing documentation is the most common reason FAT sessions are delayed or invalidated. The table below maps each required document to its owner, the stage at which it must be available, and the consequence of absence.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    Document<\/th>\nOwner<\/th>\nRequired At<\/th>\nRisk If Missing<\/th>\n<\/tr>\n<\/thead>\n
    Approved single-line and schematic drawings<\/td>\nSupplier<\/td>\nFAT start<\/td>\nCannot verify wiring against design intent<\/td>\n<\/tr>\n
    Vacuum contactor datasheet (rated voltage, current, BIL, endurance class)<\/td>\nSupplier<\/td>\nFAT start<\/td>\nNo baseline for electrical test limits<\/td>\n<\/tr>\n
    Bill of Materials with part numbers and revision<\/td>\nSupplier<\/td>\nFAT start<\/td>\nCannot confirm correct components were installed<\/td>\n<\/tr>\n
    Type-test certificates (IEC 62271-106 or equivalent)<\/td>\nSupplier<\/td>\nFAT start<\/td>\nNo evidence that design class was ever validated<\/td>\n<\/tr>\n
    Calibration certificates for all test instruments<\/td>\nBuyer \/ Test Lab<\/td>\nFAT start<\/td>\nTest results are inadmissible without traceable calibration<\/td>\n<\/tr>\n
    Factory test procedure with acceptance limits<\/td>\nSupplier<\/td>\nFAT start<\/td>\nNo agreed pass\/fail criteria; disputes likely<\/td>\n<\/tr>\n
    Insulation coordination study<\/td>\nBuyer \/ Engineer<\/td>\nFAT start<\/td>\nCannot confirm BIL and clearance choices are site-appropriate<\/td>\n<\/tr>\n
    Site specification \/ purchase order technical annex<\/td>\nBuyer<\/td>\nFAT start<\/td>\nSupplier may test to generic standard, not project requirements<\/td>\n<\/tr>\n
    Packing and shipping specification<\/td>\nSupplier<\/td>\nFAT end<\/td>\nNeeded to verify contactor survives transit before SAT<\/td>\n<\/tr>\n
    Site survey data (altitude, ambient temp, humidity, pollution degree)<\/td>\nBuyer<\/td>\nSAT start<\/td>\nCannot apply derating factors or confirm installation class<\/td>\n<\/tr>\n
    Installation and commissioning manual<\/td>\nSupplier<\/td>\nSAT start<\/td>\nNo reference for torque values, clearances, or interlock checks<\/td>\n<\/tr>\n
    Transport and storage inspection record<\/td>\nBuyer \/ Logistics<\/td>\nSAT start<\/td>\nNo evidence of condition between FAT and site arrival<\/td>\n<\/tr>\n
    As-built drawings (post-FAT revision)<\/td>\nSupplier<\/td>\nSAT start<\/td>\nSAT wiring checks reference pre-FAT drawings, not actual hardware<\/td>\n<\/tr>\n
    FAT sign-off report<\/td>\nBuyer + Supplier<\/td>\nSAT start<\/td>\nSAT cannot begin on equipment with no accepted FAT record<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    \n

    Electrical and Mechanical Tests Required at Factory Acceptance<\/h2>\n

    Every measurement taken during FAT becomes a reference point for SAT comparison and future maintenance benchmarks.<\/p>\n

    Electrical Tests<\/h3>\n

    Hi-Pot Dielectric Withstand<\/strong><\/p>\n

    \n\n\n\n\n\n\n\n\n
    Rated Voltage (kV)<\/th>\nAC Hi-Pot Level (kV rms, 1 min)<\/th>\nDC Hi-Pot Level (kV)<\/th>\n<\/tr>\n<\/thead>\n
    <= 3.6<\/td>\n10<\/td>\n14<\/td>\n<\/tr>\n
    7.2<\/td>\n20<\/td>\n28<\/td>\n<\/tr>\n
    12<\/td>\n28<\/td>\n40<\/td>\n<\/tr>\n
    17.5<\/td>\n38<\/td>\n54<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n

    Vacuum Integrity Test<\/strong><\/p>\n

    \n\n\n\n\n\n\n\n
    Contactor Rating<\/th>\nTypical Acceptable Contact Resistance<\/th>\n<\/tr>\n<\/thead>\n
    Up to 400 A<\/td>\n<= 100 micro-ohm per pole<\/td>\n<\/tr>\n
    400 A – 800 A<\/td>\n<= 60 micro-ohm per pole<\/td>\n<\/tr>\n
    > 800 A<\/td>\nPer manufacturer’s datasheet<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n

    Mechanical Tests<\/h3>\n\n\n\n\n\n\n\n
    Parameter<\/th>\nTypical Acceptable Range<\/th>\n<\/tr>\n<\/thead>\n
    Contact gap (12 kV class)<\/td>\n8-12 mm per pole<\/td>\n<\/tr>\n
    Contact wipe<\/td>\n2-4 mm per pole<\/td>\n<\/tr>\n
    Pole-to-pole gap variation<\/td>\n<= 1 mm<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    \"Factory
    FAT benchmarks establish the baseline for dielectric, resistance, timing, and mechanical acceptance.<\/figcaption><\/figure>\n

    FAT Test Summary<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n
    Test<\/th>\nStandard Reference<\/th>\nPass Criterion<\/th>\nFailure Action<\/th>\n<\/tr>\n<\/thead>\n
    Hi-pot dielectric withstand<\/td>\nIEC 62271-106<\/td>\nNo breakdown; leakage < limit<\/td>\nReplace interrupter; investigate insulation<\/td>\n<\/tr>\n
    Vacuum integrity<\/td>\nIEC 62271-106 \/ manufacturer spec<\/td>\nNo gap breakdown; pressure < 10^-3 Pa<\/td>\nReplace interrupter before shipment<\/td>\n<\/tr>\n
    Contact resistance<\/td>\nIEC 62271-1<\/td>\nWithin limit; poles within 10% of each other<\/td>\nInspect contacts; verify spring force<\/td>\n<\/tr>\n
    Insulation resistance<\/td>\nIEC 60060-1<\/td>\n>= 1,000 Mohm at 1 kV<\/td>\nInvestigate moisture or contamination<\/td>\n<\/tr>\n
    Coil pickup\/drop-out voltage<\/td>\nManufacturer spec<\/td>\nCloses at 85%; opens at <= 75% rated<\/td>\nAdjust or replace coil assembly<\/td>\n<\/tr>\n
    Mechanical endurance cycling<\/td>\nIEC 62271-106<\/td>\nNo failure in 50-100 cycles<\/td>\nIdentify binding point; re-test<\/td>\n<\/tr>\n
    Operating time<\/td>\nManufacturer spec<\/td>\nWithin +\/-15% of baseline; pole asymmetry <= 3 ms<\/td>\nRealign mechanism<\/td>\n<\/tr>\n
    Contact wipe and gap<\/td>\nManufacturer spec<\/td>\nWithin dimensional tolerance<\/td>\nAdjust mechanism; re-measure<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    \n

    Tools and Acceptance Sources Reference<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    Instrument \/ Source<\/th>\nPurpose<\/th>\nAcceptance Reference<\/th>\n<\/tr>\n<\/thead>\n
    DC micro-ohmmeter (>= 100 A injection)<\/td>\nContact resistance measurement<\/td>\nManufacturer datasheet; IEC 62271-1<\/td>\n<\/tr>\n
    1 kV \/ 2.5 kV megohmmeter<\/td>\nInsulation resistance<\/td>\nIEC 60060-1; project specification<\/td>\n<\/tr>\n
    AC hi-pot test set (calibrated)<\/td>\nDielectric withstand<\/td>\nIEC 62271-106 voltage tables<\/td>\n<\/tr>\n
    Contact timing analyzer<\/td>\nClose and open time measurement<\/td>\nManufacturer spec; +\/-15% of FAT baseline<\/td>\n<\/tr>\n
    Calibrated torque wrench<\/td>\nTerminal and busbar connection torque<\/td>\nManufacturer installation manual<\/td>\n<\/tr>\n
    Feeler gauge \/ manufacturer go\/no-go tooling<\/td>\nContact gap and wipe<\/td>\nManufacturer dimensional spec<\/td>\n<\/tr>\n
    Infrared thermometer \/ thermal camera<\/td>\nTermination temperature rise during loaded SAT<\/td>\nIEC 60529 \/ project thermal limits<\/td>\n<\/tr>\n
    Power quality analyzer or oscilloscope<\/td>\nInrush current capture at first load energization<\/td>\nProject protection coordination study<\/td>\n<\/tr>\n
    Relay test set<\/td>\nEnd-to-end protection trip injection<\/td>\nProject relay settings schedule<\/td>\n<\/tr>\n
    OEM installation and commissioning manual<\/td>\nTorque values, clearances, interlock sequences<\/td>\nManufacturer document<\/td>\n<\/tr>\n
    Project specification \/ purchase order technical annex<\/td>\nSite-specific acceptance thresholds<\/td>\nBuyer-issued document<\/td>\n<\/tr>\n
    IEC 62271-106<\/td>\nFAT\/SAT test levels and procedures<\/td>\nIEC (current edition)<\/td>\n<\/tr>\n
    ANSI\/IEEE C37.66<\/td>\nVacuum contactor requirements (North American projects)<\/td>\nIEEE (current edition)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    \n

    Site Acceptance Testing: Structure and Field Scenario<\/h2>\n

    SAT confirms that a vacuum contactor performs correctly within its actual installed environment, validating integration: cabling, control voltage levels, upstream protection coordination, enclosure thermal behavior, and specific load characteristics.<\/p>\n

    Stage 1 — Pre-Energization Checks (de-energized, locked out)<\/strong>
    \nStage 2 — Control Power and Functional Verification<\/strong><\/p>\n

    Field Scenario: 6.6 kV Contactor at a Coastal Pump Station MCC<\/h3>\n
    \"Site
    SAT reveals installation issues such as voltage drop, moisture ingress, and hot terminations that FAT cannot catch.<\/figcaption><\/figure>\n
    \n

    How to Evaluate and Compare Supplier FAT\/SAT Matrix Completeness<\/h2>\n

    Score each supplier’s submission against the criteria below. Assign points only when verifiable evidence — test records, calibration certificates, sign-off sheets — is attached.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    Evaluation Category<\/th>\nMax Points<\/th>\nWhat Earns Full Score<\/th>\nCommon Shortfall<\/th>\n<\/tr>\n<\/thead>\n
    Dielectric and insulation tests<\/td>\n20<\/td>\nHi-pot at rated voltage plus BIL impulse, individual serial numbers logged, pass\/fail limits stated<\/td>\nHi-pot performed on batch sample only; no per-unit record<\/td>\n<\/tr>\n
    Contact gap and travel measurement<\/td>\n15<\/td>\nGap measured with calibrated gauge, travel curve plotted, min\/max limits per spec<\/td>\nGap stated as “within tolerance” with no numerical result<\/td>\n<\/tr>\n
    Vacuum integrity verification<\/td>\n15<\/td>\nHi-pot or power-frequency withstand across open contacts per IEC 62271-106; dated result per unit<\/td>\nVacuum integrity assumed from factory date code; no test performed<\/td>\n<\/tr>\n
    Coil operate\/release voltage<\/td>\n10<\/td>\nTested at 85% and 110% of rated control voltage at actual site ambient temperature<\/td>\nTested only at nominal voltage in conditioned lab<\/td>\n<\/tr>\n
    Mechanical endurance sample<\/td>\n10<\/td>\nCycle count documented with minimum threshold stated; spring force verified post-test<\/td>\nEndurance data from type-test report only; not from production batch<\/td>\n<\/tr>\n
    Environmental condition logging<\/td>\n10<\/td>\nAmbient temperature, humidity, altitude, and vibration recorded at time of each SAT test<\/td>\nSAT forms lack environmental data fields<\/td>\n<\/tr>\n
    Calibration traceability<\/td>\n10<\/td>\nAll instruments traceable to national standard; calibration due dates visible on certificates<\/td>\nCalibration stickers present but expiry dates not checked against test date<\/td>\n<\/tr>\n
    Sign-off chain completeness<\/td>\n10<\/td>\nManufacturer, independent inspector, and client representative signatures on each test record<\/td>\nClient sign-off blank or obtained after energization<\/td>\n<\/tr>\n
    Non-conformance handling<\/td>\n5<\/td>\nOut-of-tolerance results documented with disposition: rework, retest, or accept-with-deviation<\/td>\nNC events absent from record (statistically implausible for large orders)<\/td>\n<\/tr>\n
    Revision and change control<\/td>\n5<\/td>\nMatrix version number, revision history, and applicability to specific purchase order referenced<\/td>\nGeneric template with no project-specific identification<\/td>\n<\/tr>\n
    Total<\/td>\n110<\/td>\n<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    Interpretation:<\/strong>
    \n– 95-110 points: Matrix is substantially complete. Proceed to contract with minor clarification requests.<\/p>\n

    \n

    Sign-off Criteria and Handover Record Requirements<\/h2>\n

    Final acceptance converts a tested contactor into a commissioned asset. Without a defined sign-off protocol, test data loses its traceability value.<\/p>\n

    Witness Levels<\/h3>\n\n\n\n\n\n\n\n
    Witness Level<\/th>\nDefinition<\/th>\nTypical Role<\/th>\n<\/tr>\n<\/thead>\n
    W — Witness<\/td>\nHold point; work stops until authorized witness signs<\/td>\nOwner’s engineer, third-party inspector<\/td>\n<\/tr>\n
    R — Review<\/td>\nRecord reviewed and approved before next stage<\/td>\nEngineering manager, QA lead<\/td>\n<\/tr>\n
    I — Information<\/td>\nCopy filed; no hold required<\/td>\nSite commissioning team<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

    Mandatory Handover Documents<\/h3>\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    Document<\/th>\nContent Required<\/th>\nSign-off Authority<\/th>\n<\/tr>\n<\/thead>\n
    FAT test report<\/td>\nAll factory test results, instrument calibration certificates, NCR log with dispositions<\/td>\nManufacturer QA + witness engineer<\/td>\n<\/tr>\n
    SAT commissioning record<\/td>\nSite test results mapped to FAT baseline, as-installed wiring diagrams<\/td>\nSite commissioning lead + owner’s engineer<\/td>\n<\/tr>\n
    Non-conformance report log<\/td>\nEvery deviation raised, corrective action taken, re-test result, closure signature<\/td>\nQA manager<\/td>\n<\/tr>\n
    Instrument calibration register<\/td>\nCertificate reference, expiry date, and traceability standard for every instrument used<\/td>\nTest supervisor<\/td>\n<\/tr>\n
    Insulation resistance baseline record<\/td>\nPhase-to-phase and phase-to-earth IR values at handover, for future maintenance trending<\/td>\nCommissioning lead<\/td>\n<\/tr>\n
    Contact resistance baseline record<\/td>\nPer-phase resistance values at handover<\/td>\nCommissioning lead<\/td>\n<\/tr>\n
    Operating time record<\/td>\nClose and open time measurements at handover<\/td>\nCommissioning lead<\/td>\n<\/tr>\n
    As-built drawing package<\/td>\nFinal single-line, control schematic, terminal schedule<\/td>\nEngineering lead<\/td>\n<\/tr>\n
    Warranty activation form<\/td>\nSerial numbers, factory test date, SAT completion date, warranty period start<\/td>\nOwner’s contract manager<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    \"Handover
    Final acceptance depends on signed test records, calibration traceability, and a complete handover package.<\/figcaption><\/figure>\n
    \n

    Procurement Checklist: Specifying a Compliant FAT\/SAT Package<\/h2>\n

    Use this checklist before issuing a purchase order or inviting a vendor to bid.<\/p>\n