Scope of this technical record
Use this hub when an ATV61 / ATV71 case needs to route output faults, DC-link voltage faults or command/reference trouble into the right field and drive evidence path.
ATV61 / ATV71 service work involves hazardous DC-link voltage, motor cables and braking circuits. Isolate and verify discharge before internal access or motor-cable work.
ATV61 / ATV71 output-fault service route
The refined Schneider cluster keeps OCF and SCF on evidence order before repair or replacement decisions.
Service decision matrix
This cluster answers one service question: is the ATV61 / ATV71 output fault a setup/load case, field output case, or drive-side repair case?
| Technician situation | Decision needed | Evidence that resolves it |
|---|---|---|
| OCF on acceleration | Load/ramp versus output hardware | Motor data, ramp, load and brake evidence |
| SCF on enable | External short versus bridge fault | Insulation, terminal and transistor/static evidence |
| Fault after module replacement | Root cause still present? | Driver/current feedback and external path proof |
Route ATV61 / ATV71 cases by symptom family
OCF and SCF ask whether output current or short-circuit evidence is real and where it originates. OSF and USF ask whether the DC link is being driven high or low by supply, load, precharge, braking or sensing evidence. Command/reference cases ask whether the drive is being told to run correctly before a hardware fault is assumed.
The hub is built for field-service decisions. A pump or fan fault, a hoist/brake-release problem, a terminal-source problem and a failed power stage can look similar from the operator panel. The route must separate them before a power board or module is ordered.
What to collect before replacing an ATV board
For OCF/SCF, collect fault timing, motor data, acceleration, brake release, motor-cable insulation and output static evidence. For OSF/USF, collect input voltage, contactor/fuse state, DC bus reading, deceleration ramp, braking path and load inertia. For command problems, collect local/remote state, terminal photos, run permissive and analog or communication reference evidence.
The same series page links the output, voltage and terminal routes because a real service case may move from one to another. For example, a USF report may actually begin with a line-contactor problem, while a no-run report may be a terminal-source problem rather than a failed inverter.
ATV61 / ATV71 first-route selector
| Observed condition | First evidence route | Avoid this shortcut |
|---|---|---|
| OCF | Load, ramp, motor data, motor cable and current-feedback route | Power board first |
| SCF | Motor/cable short, output bridge and gate-driver boundary | Repeated reset |
| OSF | High line, regeneration, ramp, braking resistor/chopper and bus feedback | Control board first |
| USF | Input supply, fuses, contactor, precharge and DC-link route | Capacitor assumption only |
| Ready but no run | Command source, terminal wiring, run permissive and reference route | Replacing inverter hardware |
Field record checklist
- Exact ATV61/ATV71 type and frame
- Fault code and first trip order
- Machine state and load condition
- Motor/cable insulation result
- Input and DC-link evidence
- Terminal wiring photos and command source
Technical basis and reference documents
This is an independent editorial technical reference. Original manufacturer documentation remains controlling for installation, repair and commissioning decisions.
Defines OCF as a hardware current limit trip and lists motor-control, inertia, load and blockage checks.
Routes SCF1 through drive output, motor cable, motor insulation and transistor-test evidence.
Supports L1/L2/L3 and PA/PC DC-bus measurement evidence for undervoltage cases.
Fault records
The Altivar drive trips on OCF at run command, during acceleration or when the load changes.
The drive reports SCF or trips instantly when the output bridge is enabled.
The Altivar drive reports OSF at power-up, while idle, during deceleration, on a regenerative load, or after braking hardware has been changed.
The Altivar drive reports USF at power-up, drops ready state, trips after a run command, or shows undervoltage when the plant supply or line contactor changes state.
Board and assembly records
Captures OSF and USF evidence around line voltage, fuses, contactor timing, precharge, DC-link measurement, brake chopper, braking resistor and previous repair history before a power-board decision.
Captures command source, run permissive, analog reference, relay outputs and external fault evidence before hardware replacement decisions.
Supports OCF/SCF routing by recording motor disconnected result, output static checks, gate-driver concerns and previous module replacement evidence.
Circuit and diagnostic records
Routes OSF and USF evidence through the full energy path: L1/L2/L3 input, fuses, contactor, rectifier, precharge, DC-link capacitors, PA(+)/PC(-) bus measurement, brake chopper and braking resistor route.
Routes OCF and SCF evidence through motor cable, motor insulation, output terminals, optional output devices, IGBT bridge, current detection and gate-driver integrity.
Captures start/stop, run permissive, direction, analog reference, relay-output and external fault evidence before a drive hardware conclusion is made.
ATV61/ATV71 trips on OCF overcurrent or SCF short circuit at start, ramp or load.
ATV61/ATV71 reports OSF overvoltage or USF undervoltage during power-up, line transition, run, load change, stop or deceleration.
Drive is ready but does not run, runs from keypad but not terminals, or speed reference is missing/unstable.
Turn this record into a qualified service request
A repair decision is much more reliable when the request includes the exact identity of the drive, the first fault evidence and the machine condition when the symptom appeared.
- Complete drive type code / MLFB or nameplate model
- Fault code, fault value and first event before reset
- When the event appears: power-up, enable, ramp, run, decel or stop
- Motor/cable connected or isolated during the symptom
- Visible board, option-card, module and connector identifiers
- Previous repair history, replacement parts and repeat-failure pattern