Engineering · Motors & Drives
VFD Parameter Configuration
Which settings must be right before a drive runs a motor, and in what order?
A drive only controls a motor well if it knows the motor. The order is always the same: take the nameplate data and enter it for the right connection, choose the control mode, run an autotune if the mode needs one, set the limits and ramps, then configure the inputs and outputs and test. This page walks through each step with tools you can change: a nameplate decoder with the star or delta terminal links, a control mode chooser, an autotune planner, a ramp and limit simulator, start/stop wiring and speed reference scaling, and two worked examples. Parameter names and ranges differ between makers, so always follow the drive manual.
| Drive parameter | Value to enter | Where it comes from |
|---|
A dual-voltage motor has two ratings, for example 400 V delta or 690 V star. The terminal links must match the supply, and the drive is given the voltage, current and connection that are actually wired. Current is estimated from power, efficiency and power factor: always enter the nameplate value, never the estimate. Enter the speed exactly as printed, because the drive uses the difference from synchronous speed to find the slip.
| Mode | Typical use | Speed regulation | Low-speed torque | Needs |
|---|
| Type | What happens | What it measures | Notes |
|---|
| Parameter | Typical setting | Purpose |
|---|
The simulator asks the drive to ramp a motor to full speed, hold, and ramp down. The motor needs enough torque to follow the ramp, and while slowing down a load with inertia sends energy back into the drive. Torque and inertia are simplified (a constant load torque and a single mechanical time constant), and the regeneration rating is a relative guide only.
The drive raises the output voltage in step with frequency to keep the motor flux constant. Boost lifts the voltage at low frequency to overcome the stator drop. Above base frequency the voltage stays at its maximum and torque falls.
With 2-wire control the start command is a maintained contact, so the drive runs for as long as it is closed, and may start again by itself when power returns. With 3-wire control a momentary start button and a normally closed stop button are used and the drive holds the run state itself, so power loss always needs a new start. Choose the one that suits the machine’s safety assessment.
| Function | Typical terminal |
|---|
| Parameter | Setting | Why |
|---|
Parameter names, numbers and defaults differ between drive makers. Settings here are typical starting points to be confirmed in the drive manual and checked on the machine. Isolate and lock out before wiring or changing connections.