ABB ACS320 Supplemental Manual page 8

INSTALLATION
WIRING SCHEMATICS
NOTE: Pre-set speeds override any
Frequency (Speed) inputs.
Use switches across terminals
9-14 and 9-15 on the VFD.
Install Leader-Follower connection
wiring if desired to operate 2nd
VFD at the same speeds.
F7 EXAMPLE OF OPERATION OF 2 VFDS BY A CO2 CONTROLLER.
8 RENEWAIRE.COM ABB VFD SUPPLEMENTAL MANUAL
ABB VARIABLE FREQUENCY DRIVES
USING VFD PRESETS FOR THE SPEED SIGNALS
The VFD can be programmed with 3 pre-set speeds. Contact switches can then be used to direct the VFD
to operate at one of those speeds. See ABB manuals for additional options. Leader-follower wiring can also
be used to make a second VFD operate at the same speed as the fi rst VFD.
USE OF 2 SWITCHES TO COMMAND THE VFD
F6
TO OPERATE AT ANY OF 3 PRE-SET SPEEDS.
USE WITH A CO2 CONTROLLER
The example below corresponds to the example in the section "Scaling and Response to Analog Inputs".
The scaling parameter settings for the FA VFD in your application are likely to be different.
1.800.627.4499
If both VFDs are to run at the same speed, no scaling
parameters need be applied to the EA VFD in this example
since it is controlled as a "Follower".
If it is desired that the VFDs should shut off when CO2
levels drop below a setpoint, connect the Normally
Open contacts of the CO2 controller (terminals 3 & 4)
to terminals 9 & 12 of the FA VFD. Adjust the operating
parameters of the CO2 controller to set the relay setpoint.