Yaskawa GA800 F045 Fault — What It Means
The fault code F045 is not documented in Yaskawa GA800 VFD manuals. Yaskawa GA800 drives use two-letter alphanumeric fault codes such as OV (overvoltage), LU (low voltage), SC (short circuit), OF (output fault), and F01. If your display shows what appears to be F045, you may be misreading the screen, looking at a different manufacturer’s drive, or seeing an internal project file or trend log code rather than an actual drive fault.
The most commonly reported GA800 fault that users sometimes mislabel is OV (overvoltage). This fault trips when the DC bus voltage exceeds the safe threshold (typically above 800 V DC for 480 V class drives) and is a protective shutdown to prevent damage to the power stage components. It is frequently triggered by speed-search functions, incorrect ramp or deceleration times, or braking misconfigurations.
Before You Replace Anything
Technicians sometimes replace power boards or capacitors when the real issue is a parameter setting. Always check the modified parameter log and fault history in the drive menu before ordering parts.
Common Causes
- Misreading the display (~40%) The display may show OV, LU, or another valid code that appears similar to F045 when viewed at an angle or with poor lighting.
- Wrong manufacturer or drive model (~25%) F045 may be a valid code for a Siemens, ABB, or other brand drive that is installed nearby or that you are confusing with the Yaskawa unit.
- Speed-search function enabled (~15%) Parameter C4-01 set to enable causes the drive to apply voltage while searching for motor speed, leading to overvoltage spikes that trip OV.
- Incorrect deceleration time (~10%) Parameter C1-04 set too fast causes the motor to act as a generator and pump energy back into the DC bus, triggering an overvoltage trip.
- Braking resistor misconfigured or missing (~6%) Parameter C5-01 set incorrectly or no external braking resistor installed when high-inertia loads require one.
- Operating in closed loop vector without tuning (~4%) CLV or AOLV modes are unstable without proper pre-control and auto-tuning, causing DC bus instability.
Quick Diagnosis
Answer these to narrow it down fast.
Does the drive display show exactly two characters (letters or numbers) for the fault code?
No: You may be looking at a different manufacturer's drive, a trend log entry, or a misread display. Verify the drive model and consult the correct manual.
Does the drive display show OV when it trips?
No: Note the exact code shown and verify it matches a code in the GA800 fault table before proceeding.
Can you find F045 listed in the GA800 manual fault code table?
No: The code does not exist for GA800. Confirm the drive brand and model, then consult the correct documentation.
Step-by-Step Fix
- Verify the drive model and fault code. Look at the nameplate on the drive to confirm it is a Yaskawa GA800 series. Press F2 to enter the menu, then navigate to the fault log to read the exact fault code the drive has recorded.
- Check for overvoltage (OV) fault. If the drive shows OV, press F2, select Menu, scroll to Modified Parameter or Fault Log, and review parameter C4-01 (Speed Search Enable). Set it to 0 to disable speed search.
- Increase deceleration time. Navigate to parameter C1-04 (Deceleration Time) and increase the value to 5 to 10 seconds to prevent the motor from regenerating excessive voltage back into the DC bus during stopping.
- Verify braking resistor settings. If your application uses an external braking resistor, check parameter C5-01 (Braking Resistor Type) and confirm it matches the installed resistor. Inspect the physical resistor connections and resistance value.
- Switch to open loop vector mode. If the drive is configured for closed loop vector (CLV) or auto vector (AOLV), switch to open loop vector (OLV) mode until you can perform proper motor tuning and pre-control setup.
- Inspect input power supply. Use a multimeter to measure incoming line voltage and check for fluctuations, harmonics, or weak phases that may cause DC bus instability.
- Consult the GA800 manual for the actual code. If none of the above applies, locate the GA800 technical manual for your drive model and cross-reference the displayed code in the fault code table to find the correct troubleshooting procedure.
Parts Often Needed
| Part | Notes |
|---|---|
| Braking Resistor (external, if required by application) | Amazon | Only needed for high-inertia or frequent-stop applications. Consult your GA800 model’s table for resistance and wattage rating. |
| DC Bus Capacitor (internal drive component) | Amazon | Replace only if voltage measurements confirm capacitor failure. Requires qualified technician and high-voltage safety training. |
When to Call a Pro
Call a qualified drives technician or industrial electrician if you cannot locate the fault code in the GA800 manual, if the drive continues to trip after parameter adjustments, or if you need to replace internal power components such as DC bus capacitors or IGBT modules. High-voltage DC bus work requires lockout/tagout procedures, discharge equipment, and safety training. A technician can also perform motor auto-tuning, verify braking resistor sizing, and check for power supply issues such as harmonics or phase imbalance that require specialized test equipment.
Rough cost: A pro service call runs about $200-500.