Most modern industrial variable-frequency drives (VFDs) such as ABB ACS, Schneider Altivar, Siemens SINAMICS and Danfoss VLT support Modbus RTU and/or TCP as a control interface, with a register map documented by the manufacturer.
True
The standard "drive over Modbus" pattern is: the drive exposes registers for start/stop command, speed setpoint, current reading, speed reading and fault status; a Modbus master (PLC or BMS) writes the commands and reads the feedback. A typical cycle is 100-500 ms for slow applications (water pumps) and 10-50 ms for faster ones (machine spindles). The reference document is the vendor "Modbus mapping table" or "Communication protocol manual". Always verify the byte order and the available sub-functions before integration.
Lock the drive's parameter set with a password before going into production: a stray Write Register on the wrong address can change a critical ramp time or motor current limit.
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