Yaskawa GA800 A.146 Fault — What It Means
The GA800 fault code A.146 does not appear in publicly available Yaskawa alarm tables or technical documentation at this time. Yaskawa GA-series drives use alphanumeric fault and alarm codes that are model-specific and sometimes depend on installed option cards such as encoder feedback or communication modules. Because the exact meaning of A.146 is not verified, you must consult the alarm code table in your GA800 instruction manual or contact Yaskawa technical support with your drive’s nameplate model number and serial number. The drive will log the fault in its fault history menu, which will show the exact code and any accompanying data that can help narrow the circuit or subsystem involved.
In general, Yaskawa VFD troubleshooting starts with reading the digital operator display, pulling the fault history, inspecting all field wiring for loose connections or damage, checking the motor and load for mechanical binding or insulation faults, and clearing the fault only after the underlying issue is corrected. If the fault returns immediately after a power cycle, the cause is still present in the wiring, motor, load, or a control or option board inside the drive. Do not replace the entire drive or any board until you have verified the fault definition and followed the diagnostic steps in the manual.
Before You Replace Anything
Technicians sometimes replace the entire VFD or the control board without first checking field wiring, motor insulation, and encoder or option-card connections. Always pull the fault history, verify all terminations, and consult the manual’s alarm table before ordering parts.
Common Causes
- Undefined or option-specific alarm code (~40%) The A.146 code may be specific to an installed option card or firmware revision not covered in general documentation.
- Field wiring fault (~25%) Loose or damaged control wiring, encoder cable, or shield grounding can trigger obscure alarm codes on GA-series drives.
- Encoder or feedback device fault (~20%) If a pulse-generator or encoder option is installed, a wiring break, ground fault, or failed encoder can produce an uncommon alarm.
- Control board or option card hardware fault (~10%) A failed component on the control board or an option module may generate an alarm code that does not appear in the base drive table.
- Parameter corruption or firmware mismatch (~5%) Corrupted drive parameters or a firmware version that uses a non-standard alarm set can display unexpected codes.
Quick Diagnosis
Answer these to narrow it down fast.
Does the drive display the same A.146 code after a power cycle?
No: The fault may have been transient noise or a momentary load condition. Monitor the drive and check for loose connections.
Is an encoder, PG card, or communication option installed in the drive?
No: The fault is likely related to main power, motor wiring, or the control board. Inspect incoming line and motor leads.
Does the drive's fault history show any accompanying data or a secondary alarm?
No: Without supporting data, contact Yaskawa support with your full model number and serial to identify the code.
Step-by-Step Fix
- Verify the displayed code by reading the digital operator keypad carefully and confirming it shows A.146, not a similar-looking code such as A.145 or A.148.
- Pull the fault history from the drive’s menu to see if the fault has logged multiple times or if there is additional diagnostic data stored with the alarm.
- Consult your GA800 instruction manual alarm code table or download the latest manual from the Yaskawa website using your drive’s exact model number from the nameplate.
- Inspect all field wiring including incoming line power, motor leads, control wiring, encoder or PG cables if installed, and shield and ground terminations at both the drive and motor ends.
- Check the motor and load for mechanical binding, bearing failure, or any condition that would cause excessive current or a feedback signal loss.
- Power cycle the drive after correcting any wiring or mechanical issues, then monitor the operator display to see if the fault clears or returns immediately.
- Contact Yaskawa technical support if the code is not listed in your manual or if the fault persists after wiring and load checks, and have your drive model, serial number, and fault history data ready.
Parts Often Needed
| Part | Notes |
|---|---|
| Yaskawa GA800 control board | Amazon | Order by your drive’s exact model and serial number; only replace after verifying the fault points to the board and not field wiring. |
| Yaskawa encoder option card | Amazon | If your drive has a pulse-generator or encoder feedback option and the fault is encoder-related; confirm part number from your manual. |
When to Call a Pro
Call a qualified VFD technician or Yaskawa-authorized service partner when the A.146 fault persists after you have checked all field wiring and the code is not defined in your manual. VFD diagnostics often require specialized test equipment to measure control voltages, encoder signals, and board-level circuits. A technician can decode option-specific or firmware-specific alarms, verify whether the control board or an option card has failed, and order the correct replacement part using your drive’s full model and serial number. Do not attempt to open the drive or replace internal boards if you are not trained in high-voltage DC bus safety, because lethal voltage can remain stored in the bus capacitors even after input power is removed.
Rough cost: A pro service call runs about $200–600 depending on whether the fix is wiring, an option card, the control board, or the drive itself.