Emerson VSG Operation Manual page 37

8. Max Speed Detect: Setting for PLC program detection of maximum speed. This setting will not limit
the speed of the VFD. Generally, this setting is useful only when sequencing of multiple devices is
used.
9. Minimum Speed: This is the minimum speed that the PLC will send to the VFD. This is active in
Manual Mode and in Auto Mode.
Adjustment Limit: This is the maximum amount of change in speed per adjustment. If the Calculated Adjust-
ment is greater than the Adjustment Limit value, the PLC output will only change the amount of the Adjust-
ment Limit. If the Calculated Adjustment is less than the Adjustment Limit value, the PLC output will change
the amount of the Calculated Adjustment. The Adjustment Limit is used in conjunction with the Gain to
prevent target overshooting.
10. Gain: This value is factory set to 2.50 but may be set from 0.1 to 99. For VFDs, Gain is a multiplica-
tion factor used in a calculation to determine an adjustment to the speed each set interval. This
interval is defined as the Increase Rate or Decrease Rate. Factory settings for Increase Rate and De-
crease Rate are 2 to 5 seconds.
Manual Button:
Choosing Manual will do the following:
1. The fan Output Mode will remain Manual Mode.
2. Manual Speed: This setting becomes accessible only when the Manual Button is chosen. Enter the
desired speed (%) for the VFD.
VSG/VSSG • Compact Logix PLC Manual •Vilter/Emerson • 35391CL
Motor Speed Setpoints & Control Screen
37