WEG CFW500 troubleshooting
The CFW500 is WEG’s compact general-purpose frequency inverter. Faults show as Fxxxx and alarms as Axxxx. On a fault the inverter blocks the IGBTs and the motor coasts to a stop; an alarm warns of a condition that may lead to a fault if it is not corrected. The inverter keeps the last three faults with the current, DC link voltage, frequency and temperature at the trip.
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Try Free Drive Diagnostic Upload a photo of the alarm screen, the fault history or a data export. InduQT compares the evidence and suggests the next useful checks.
How it reports faults
- In the fault state the main HMI display shows the fault number as Fxxxx. Press ESC to browse; Fxxxx moves to the secondary display until the fault is reset. Alarms show as Axxxx the same way.
- P0048 shows the present alarm and P0049 the present fault.
- Fault history keeps the last three faults: P0050, P0060 and P0070 hold the fault numbers; P0051/P0061/P0071 the output current; P0052/P0062/P0072 the DC link voltage; P0053/P0063/P0073 the output frequency; P0054/P0064/P0074 the IGBT temperature; P0055/P0065/P0075 the logical status (P0680) at the trip.
- A fault can be reset by a digital input programmed for Fault Reset (once the cause is gone) or by bit 7 of the control word. P0340 sets an automatic reset time (0 = disabled); auto-reset is locked if the same fault occurs three times within 30 seconds of the reset.
Fault codes
| Code | Name |
|---|---|
| F0021 | Undervoltage on the DC link |
| F0022 | Overvoltage on the DC link |
| F0070 | Overcurrent/short-circuit |
| F0072 | Motor overload |
| F0074 | Ground fault |
| F0051 | IGBTs overtemperature |
Evidence to collect
- Photo of the HMI showing the Fxxxx code
- Fault history P0050–P0055 (and P0060–P0075 for earlier faults)
- Inverter model, rated current (P0295), supply voltage setting (P0296) and software version
- Motor rating plate and motor rated current (P0401)
- What the machine was doing at the trip
Work on fuel trains, burners, pressure vessels and electrical equipment must be done by qualified personnel following the manufacturer’s documentation and local codes. Never bypass a safety device or interlock.