



A pump motor should be connected in the star or delta arrangement that matches the VFD output voltage and motor nameplate. Do not choose the connection by habit; choose it from the motor voltage markings and the actual drive voltage class.
| Item | Reference Selection |
|---|---|
| Motor | Three-phase pump motor with clear nameplate voltage |
| Connection | Star or delta according to nameplate and VFD output voltage |
| Input | Site supply matched to selected VFD |
| Output | VFD output voltage matched to motor winding requirement |
| Protection | Motor current, overload and phase-loss checks |
| VFD | AUSENIST pump VFD selected by motor rated current |
Remote start-stop control for a pump VFD is normally done through digital input terminals configured for run command, stop command or forward operation. The exact wiring depends on the selected VFD model, control mode and whether the signal comes from a switch, float, relay or PLC.
| Item | Reference Selection | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Command | Digital input terminal for remote run/stop | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Signal Source | Switch, float switch, pressure switch, relay or PLC contact | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Speed Reference | Keypad, analog input, PID setpoint or external command | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Safety | Emergency stop and protection circuit as required | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Feedback | Run, fault or ready relay output if needed | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| VFD | AUSENIST pump VFD configured for terminal control |
| Item | Reference Selection |
|---|---|
| Pump | Booster, irrigation, transfer or circulation pump |
| Input | Stable supply voltage matched to VFD rating |
| Wiring | Breaker, cable and terminals checked under load |
| Control | Ramp time suitable for supply capacity |
| Protection | Undervoltage, phase-loss and overload protection active |
| VFD | AUSENIST pump VFD selected by motor current and supply condition |
| Item | Reference Selection |
|---|---|
| Fault Data | Fault code, fault timing and reset behavior |
| VFD Data | Model, rating label and parameter changes if known |
| Motor Data | Nameplate voltage, current, power and frequency |
| Site Data | Supply voltage, pump type, cable length and control mode |
| Photos | Wiring, motor nameplate, VFD label and panel layout |
| Support | AUSENIST review based on confirmed information |
The minimum frequency for a water pump VFD should be high enough to maintain safe motor cooling, useful pump flow and stable system pressure. There is no universal value because the correct limit depends on pump type, motor design and hydraulic demand.
| Item | Reference Selection |
|---|---|
| Pump | Centrifugal, booster, submersible or circulation pump |
| Motor | VFD-compatible three-phase pump motor |
| Limit | Minimum frequency confirmed by pump and process requirement |
| Control | PID pressure, flow command or manual speed |
| Protection | Dry-run, overload and low-pressure alarm |
| VFD | AUSENIST pump VFD selected by rated current |
Select a pump VFD pressure sensor range that covers the normal working pressure and expected high-pressure condition without being much larger than needed. A 4-20mA pressure transmitter is commonly used for constant-pressure booster systems.
| Item | Reference Selection |
|---|---|
| Pump | Booster pump or constant-pressure water supply pump |
| Sensor | Pressure transmitter with suitable range |
| Signal | 4-20mA or 0-10V according to VFD input |
| Control | PID constant-pressure control |
| Protection | High-pressure alarm and dry-run protection |
| VFD | AUSENIST pump VFD selected by motor rated current |
A water pump VFD may start and stop frequently because of narrow sleep/wake settings, leakage, wrong pressure tank pre-charge, unstable pressure feedback or demand that is too small for continuous running. The solution is usually a system adjustment, not only a parameter change.
| Item | Reference Selection |
|---|---|
| Pump | Constant-pressure booster pump |
| Sensor | Correctly scaled pressure transmitter |
| Tank | Pressure tank checked for volume and pre-charge |
| Control | PID with suitable sleep and wake settings |
| Protection | Dry-run and high-pressure alarms reviewed |
| VFD | AUSENIST pump VFD selected by motor rated current |