ABB ACH550 User Manual page 33

E-Bypass Configurations for ACH550 Drives 31
functions of these inputs is determined by the ACH550 macro selection. Refer to the
ACH550-UH User's Manual for additional information.
The ACH550 Auto Mode External Reference input is an analog input that sets the
operating speed when the ACH550 HVAC macro is selected and the drive is in the
Auto mode. When HVAC PID Control is selected, analog inputs are used for
receiving the transducer feedback "actual" signal. Refer to the ACH550-UH User's
Manual for additional information.
The Output Frequency analog output of the ACH550 provides a 4 to 20 mA signal
proportional to the drive output frequency or motor speed.
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