Schneider Electric fault record

SCF: Motor or Output Short-Circuit Fault

The drive reports SCF or trips instantly when the output bridge is enabled.

Deep search-intent fault page10 min read

Scope of this technical record

ATV61 / ATV71 SCF routing for users deciding whether a short-circuit indication belongs to motor phase-to-phase fault, output-to-ground fault, cable leakage, incorrect motor parameters, parallel motors or an internal power-bridge condition.

Safety boundary

Treat SCF as a potentially destructive output fault. Do not repeat start commands into a suspected short. Isolate motor/cable correctly and verify discharge before internal access.

ATV61 / ATV71 SCF route

1SCF variant
2Insulation
3Output terminals
4Transistor test
5IGBT boundary

SCF is a stop-condition route: prove motor and cable before bridge work.

ATV61 / ATV71 SCF short-circuit image

Schneider ATV61 ATV71 SCF short circuit insulation transistor test IGBT boundary diagram
The SCF image is deliberately conservative: prove insulation and output terminals before power-bridge repair.

Searcher intent coverage

SCF users need a safe stop/continue decision. The page treats SCF as destructive until motor, cable and transistor-test evidence say otherwise.

Observed situationDecision neededEvidence that satisfies the search
Instant SCFMotor/cable short or IGBT shortInsulation and transistor-test evidence
SCF3Ground pathPhase-to-ground insulation and moisture evidence
SCF4Power componentStatic bridge and power-component evidence

What SCF users need to know first

SCF is not a harmless reset code. Schneider public material for ATV61/ATV71 short-circuit faults points to motor short-circuit to ground or phase-to-phase, and related Schneider FAQ material highlights output short/grounding, motor parameters and leakage with parallel motors. The first editorial job is to stop repeat energizing until the external output path is separated.

The searcher’s real question is: can I safely restart, or do I need to isolate the motor cable and inspect the output bridge? The answer depends on timing and evidence. SCF at enable after a cable change is different from SCF after a power-board repair or SCF in a wet motor terminal box.

SCF timing map

Observed SCF patternFirst boundaryStop condition
Instant at enableMotor cable, terminal short, output bridgeStop repeated starts
After washdown/humidityMotor terminal box, cable insulation, contaminationOpen/inspect external output path
After motor replacementWrong wiring, phase short, motor data mismatchVerify wiring/nameplate before drive blame
With several motors in parallelLeakage current and cable/motor configurationReview installation limits and insulation
Persists with output path isolatedInternal bridge/current detection routeEscalate only with documented isolation

Safe sequence for SCF

First photograph the terminal condition and record exactly when SCF appears. Then isolate motor and cable using the correct procedure. Insulation testing must not be performed through the drive. Inspect terminal boxes, cable glands, shield termination, moisture tracks, loose strands and recent wiring work.

If the external output path is proven healthy and SCF persists under a controlled safe setup, the focus moves to static output bridge checks, gate-driver evidence and current/short-circuit detection. If a power bridge is replaced, driver and cause checks must be recorded before energizing; otherwise the same short can destroy the replacement.

SCF evidence split

EvidenceExternal routeDrive-side route
Motor/cable insulation poorStrong external routeDo not replace bridge first
Loose strand or wet terminal box foundStrong external routeRepair installation and retest safely
SCF clears with output removedExternal route primaryInternal fault not proven
SCF remains with output removed and testedExternal route weakerPower bridge/current-detection route stronger
Previous bridge replacement failedCause not removedDriver/cause investigation required

What evidence makes the page genuinely useful

A good SCF page asks for facts that change the next decision: type code, voltage class, whether the fault is SCF1/SCF2/SCF3 where shown, timing, motor/cable isolation result, terminal-box photos, moisture/cable-route evidence and previous repair work. Without that, the article can only say “short circuit possible,” which is not enough for a repair decision.

The strongest service conclusion is not a long paragraph; it is a boundary statement: external cable/motor fault confirmed, output bridge likely after isolation, parameter/configuration issue suspected, or unsafe to continue without qualified test procedure.

SCF repair-boundary notes

ConclusionRequired evidenceNext decision
External short confirmedInsulation or visual evidence outside driveRepair motor/cable before any drive replacement
Parameter/configuration suspectMotor data or parallel motor evidenceCorrect setup and retest under safe load
Internal bridge suspectExternal path isolated and static evidence abnormalEscalate to bridge/driver repair
Insufficient evidenceOnly panel code availableCollect field evidence before quote

Field record checklist

  • ATV type code, voltage class and exact SCF subtype if shown
  • Timing: enable, acceleration, running, after washdown or after repair
  • Motor/cable isolation and insulation evidence
  • Terminal box, cable gland, shield and output terminal photos
  • Motor nameplate and parallel motor configuration if applicable
  • Static bridge/driver evidence after external path is proven

Technical basis and reference documents

This is an independent editorial technical reference. Original manufacturer documentation remains controlling for installation, repair and commissioning decisions.

Schneider Electric SCF FAQSchneider Electric

Public FAQ points to motor short-circuit to ground or phase-to-phase and immediate inverter-bridge protection context.

Schneider Electric ground short-circuit FAQSchneider Electric

Public FAQ lists output short/grounding, motor parameters and significant leakage with parallel motors as causes.

Diagnostic workflow