GS VFD Overvoltage Warning: Diagnosis and Safe Response

A GS VFD reports an overvoltage warning when its measured voltage rises above the drive’s acceptable range. On the systems covered by this article, a VFD-software reading above 340 V triggers the warning.

Electrical hazard: Stop the affected movement and contact Enventek Support. Incoming-power measurements and wiring changes must be performed by a qualified electrician using the machine schematic and approved electrical-safety procedures.

Record the fault before resetting

• The exact VFD warning or fault code.
• The voltage value shown in the VFD software.
• Which drive and machine movement are affected.
• Whether the fault occurs at power-up, during acceleration, while stopping, or intermittently.
• Any recent facility-power, transformer, wiring, or VFD changes.

Likely causes

• Incoming supply voltage is too high.
• One supply leg is higher than the others or the phase voltages are unbalanced.
• The drive is connected to a supply configuration that does not match its rating or application.
• Regenerated energy during deceleration raises the DC-bus voltage.
• A wiring, grounding, parameter, or drive fault is producing an incorrect condition or reading.

Qualified-electrician checks

1. Verify the drive model, input rating, and machine schematic.
2. Measure the incoming supply using the facility’s approved procedure and compare the phase-to-phase readings.
3. Investigate and correct an abnormally high or unbalanced supply leg.
4. Inspect the VFD input wiring, disconnects, fuses, grounding, and terminal condition.
5. Provide the readings and fault history to Enventek Support before changing wiring or drive parameters.

Do not remove a supply leg unless Enventek Support confirms the exact drive and schematic. Some PickLine conveyor drives are designed to use only legs 1 and 3, but this does not apply to every VFD or motor. Applying that workaround to the wrong drive can damage equipment or create a hazardous condition.

What Correct Looks Like

After the cause is corrected, confirm that the displayed voltage remains below the warning threshold through power-up, acceleration, steady operation, and stopping. If the warning returns, stop resetting the drive and provide Enventek Support with the measured incoming voltages and exact operating point of the fault.

Escalate When

Record the exact screen message, affected component, indicator-light state, and steps already attempted. Contact Enventek Technical Support if the fault remains or the machine does not respond as expected.