Schneider Electric Altivar Machine ATV320 fault SCF1: Motor short circuit
SCF1 on a Schneider Altivar ATV320 is a motor short circuit error: the drive detected a short circuit or grounding at its output, between the drive and the motor or inside the motor.
Diagnose this with AI
Try Free Drive Diagnostic Upload a keypad photo, the fault history or a parameter export from your Schneider Electric Altivar Machine ATV320. InduQT compares the evidence and suggests the next useful checks.
When it happens
- Instantly at the run command
- While running, after cable damage or moisture ingress
- After motor or cable work
Likely causes and checks
1Motor cable damaged or shorted
- Points to it
- Trips at the instant of the run command; cable recently moved, crushed or wet.
- Check
- Lock out, wait 15 minutes, confirm DC bus below 42 Vdc, disconnect the motor cable at the drive and insulation-test it phase-to-phase and to ground.
2Motor winding or insulation failure
- Points to it
- Cable tests good; motor old, overheated or exposed to moisture.
- Check
- Insulation-test the motor windings with the motor disconnected from the drive.
3Cable capacitance or switching effects on long runs
- Points to it
- Insulation tests good; long motor cable.
- Check
- Schneider lists connecting chokes in series with the motor and reviewing [Switching frequency] SFR.
4Speed loop or brake adjustment
- Points to it
- Trips on hoisting or brake-controlled axes around brake release.
- Check
- Check the speed loop and brake settings and consider increasing [Time to restart] TTR, as Schneider lists.
Telling it apart
- SCF1 is a short at the output; SCF3 is earth leakage (Schneider notes it with several motors in parallel); SCF4 is an IGBT short (power component); SCF5 is a load short during the power-on sequence.
- OCF with healthy insulation points to load and settings rather than wiring.
- SCF1 needs a power reset unless [Extended Fault Reset] HRFC = YES.
Relevant parameters
| Parameter | Name | Why it matters |
|---|---|---|
| SFR | Switching frequency | Schneider lists switching-frequency changes among the SCF1 remedies; confirm the direction for the installation. |
| TTR | Time to restart | Increasing it is a listed remedy. |
Evidence to collect
- Error history entry for SCF1
- Insulation test results for cable and motor, each disconnected from the drive
- Motor cable length and any output choke
- SFR and TTR settings
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