55 kW VFD for pump and fan duty
The ATV21WD55N4C is a 55 kW Altivar 21 AC drive designed for variable-torque loads like centrifugal pumps and fans. An integrated Class B EMC filter meets EN 55011 Group 1 Class B emissions limits, saving panel space and external filter cost in residential or light-industrial installations. The adjustable switching frequency ranges from 6 to 16 kHz, with a derating factor applied above 8 kHz — useful for quietening motor whine at the cost of reduced continuous output current.
Transient overtorque and speed regulation
Transient overtorque capability of 120 % nominal motor torque for 60 seconds handles short-duration overloads during pump start or fan inertia ramp-up. Speed accuracy is ±10 % of nominal slip from 0.2 Tn to Tn, and an adjustable PI regulator loop allows closed-loop process control without an external controller. The drive supports Modbus RTU over a 2-wire RS-485 physical interface at 9600 or 19200 bps, with up to 247 addresses on the bus. Optional communication cards add BACnet, LonWorks, Metasys N2, or Apogee FLN for building management integration.
Lifecycle and sourcing — mature, quoted to order
No stock-holding claim is made here.