The VFD68 drive’s mode of operation is indicated by the mode of operation icons (labeled PU and EXT) on the drive’s operation panel (Figure 1).
PU Mode: The Parameter Units (PU) mode is manual control mode. In PU mode, the drive and motor are completely controlled using the buttons and the setting dial on the drive’s user interface. No external analog signals or network signals control the drive operation. The PU mode is typically used to set up, test, and troubleshoot the drive and motor operation using controlled input signal values.
EXT Mode: In the External (EXT) mode, the drive and motor respond to a signal or signals from one or two (external) analog input signal devices, such as pressure transducers or analog controllers. This is the typical mode of operation for the drive when it controls a condenser fan or other three-phase HVACR motor application.
PU/EXT Mode: In PU/EXT mode, the drive responds to the connected external signal devices and the drive setup values can be edited. The PU/EXT mode is typically used to set up your drive for initial operation, or to adjust setup parameters on an operating application.
MON Mode: Shows motor speed represented as frequency (Hz) or RPM.