ABB ACS580 vs Schneider ATV630 vs Siemens G120 VFD
A side-by-side comparison of the ABB ACS580, Schneider ATV630 and Siemens G120 VFDs on control method, overload duty rating, enclosure and fieldbus support.
VFD Sizing for Constant vs Variable Torque Loads
How to match a VFD's Normal Duty or Heavy Duty overload rating to constant-torque and variable-torque loads, with the sizing steps, overload-margin formula, ...
VFD Cable Sizing and Motor Cable Length Limits
How to size VFD motor cable for both ampacity and PWM reflected-wave voltage, and when cable length forces a dV/dt reactor or sine-wave filter.
How to Program a VFD: Basic Parameter Setup
A practical guide to VFD parameter setup: motor nameplate data, control mode selection, ramp times, I/O assignment and protection settings for correct first-...
VFD Energy Saving on Pumps and Fans: Affinity Laws
The affinity laws show why cutting a centrifugal pump or fan's speed 20% can cut its power draw nearly in half, and where that cube-law estimate breaks down ...
VFD Communication: Modbus, PROFINET and EtherNet/IP
How VFDs exchange data with a PLC over Modbus RTU, PROFINET, EtherNet/IP, and EtherCAT, and how to pick the right protocol for the plant network.
VFD Enclosure Ratings: IP20, IP55 and Cabinet Cooling
IP20, IP55 and IP66 enclosure ratings for VFDs, NEMA/UL equivalents, and how to size cabinet cooling so the drive doesn't overheat or corrode.
VFD Overload: Normal Duty vs Heavy Duty Ratings
A field guide to VFD Normal Duty and Heavy Duty overload current ratings — what the percentages mean, why the same frame gives less kW in HD, and how to size...
VFD Motor Bearing Currents and Shaft Grounding
PWM common-mode voltage induces shaft voltage on VFD-fed motors, which discharges through the bearing film as EDM pitting and fluting unless a shaft groundin...
VFD Output Filters: dV/dt, Sine Wave and Cable Length
How reflected-wave voltage forms on VFD output cables and how to choose between a dV/dt reactor, a sine-wave filter, and cable-length limits.
