My checklist for commissioning a VFD

A variable frequency drive (VFD) soft-starts a motor, controls its speed and saves energy. With the wrong parameters, though, the motor overheats, the drive keeps tripping, or the mechanics get damaged. This is the order I follow when commissioning a drive:

Before powering up

Nameplate data: Note the motor's voltage, current, frequency, speed and power.
Connection: Should the motor be wired star or delta? It must match the drive's output voltage.
Cabling: Use shielded cable between drive and motor and ground the shield properly at both ends. Very long motor cables may need an output filter.
Input protection: Input fuses or breakers should match the values in the drive manual.

Core parameters

Motor data: Enter the nameplate values into the drive.
Auto-tune: If possible, decouple the motor and run a full auto-tune; otherwise use the static tune. Vector control depends on it.
Control source: Where do start/stop and the speed reference come from? Keypad, terminals or communication (Modbus etc.).
Min/max frequency: Very low speeds can hurt cooling on pumps and fans. Don't exceed the maximum speed the mechanics can handle.
Ramp times: Too short an acceleration time causes overcurrent trips; too short a deceleration time causes overvoltage trips. High-inertia loads may need a braking resistor.
Motor overload protection: Set thermal protection to the motor's rated current.

First run

Run at a low frequency (e.g. 5–10 Hz) and check the direction of rotation. If it's wrong, swap two output phases or use the direction parameter.
Watch the current. Unexpectedly high current at no load points to a wiring or parameter error.
Increase speed gradually and listen for vibration and noise.

Common faults

Fault	Likely cause
Overcurrent while accelerating	Ramp too short, jammed load, wrong motor data
Overvoltage while decelerating	Decel ramp too short, no braking resistor
Motor overheating	Long periods at low speed, wrong thermal setting
Noise on measurements/communication	Missing shielding and grounding, cables bundled together

Last step: back up

When commissioning is done, back up the parameters and add them to the project files. If the drive is ever replaced, you can restore the same settings in minutes.

Before powering up

Nameplate data: Note the motor's voltage, current, frequency, speed and power.

Connection: Should the motor be wired star or delta? It must match the drive's output voltage.

Cabling: Use shielded cable between drive and motor and ground the shield properly at both ends. Very long motor cables may need an output filter.

Input protection: Input fuses or breakers should match the values in the drive manual.

Core parameters

Motor data: Enter the nameplate values into the drive.

Auto-tune: If possible, decouple the motor and run a full auto-tune; otherwise use the static tune. Vector control depends on it.

Control source: Where do start/stop and the speed reference come from? Keypad, terminals or communication (Modbus etc.).

Min/max frequency: Very low speeds can hurt cooling on pumps and fans. Don't exceed the maximum speed the mechanics can handle.

Ramp times: Too short an acceleration time causes overcurrent trips; too short a deceleration time causes overvoltage trips. High-inertia loads may need a braking resistor.

Motor overload protection: Set thermal protection to the motor's rated current.

First run

Run at a low frequency (e.g. 5–10 Hz) and check the direction of rotation. If it's wrong, swap two output phases or use the direction parameter.

Watch the current. Unexpectedly high current at no load points to a wiring or parameter error.

Increase speed gradually and listen for vibration and noise.

Common faults

Fault

Likely cause

Overcurrent while accelerating

Ramp too short, jammed load, wrong motor data

Overvoltage while decelerating

Decel ramp too short, no braking resistor

Motor overheating

Long periods at low speed, wrong thermal setting

Noise on measurements/communication

Missing shielding and grounding, cables bundled together