ABB ACS320 - Page 262

262 Actual signals and parameters
Group 81: PFA control
Code Description Range Resolution Default S
8103
REFERENCE STEP
1
0.0 … 100.0% 0.1% 0.0%
Sets a percentage value that is added to the process reference.
• Applies only when at least one
auxiliary (constant speed) motor is running.
• Default value is 0%.
Example: An ACS320 operates three parallel pumps that maintain water pressure in a
pipe.
• Parameter 4011 INTERNAL SETPNT sets a constant pressure reference that con-
trols the pressure in the pipe.
• The speed regulated pump operates alone at low water consumption levels.
• As water consumption increases, first one constant speed pump operates, then, the
second.
• As flow increases, the pressure at the output end of the pipe drops relative to the
pressure measured at the input end. As auxiliary motors step in to increase the flow,
the adjustments below correct the reference to more closely match the output pres-
sure.
• When the first auxiliary pump operates, increase the reference with parameter 8103
REFERENCE STEP 1.
• When both auxiliary pumps operate, increase the reference with parameter 8103
REFERENCE STEP 1 + parameter 8104 REFERENCE STEP 2.
• When three auxiliary pumps operate, increase the reference with parameter 8103
REFERENCE STEP 1 + parameter 8104 REFERENCE STEP 2 + parameter 8105
REFERENCE STEP 3.
8104
REFERENCE STEP
2
0.0 … 100.0% 0.1% 0.0%
Sets a percentage value that is added to the process reference.
• Applies only when at least two
auxiliary (constant speed) motors are running.
• See parameter 8103 REFERENCE STEP 1.
8105
REFERENCE STEP
3
0.0 … 100.0% 0.1% 0.0%
Sets a percentage value that is added to the process reference.
• Applies only when at least three
auxiliary (constant speed) motors are running.
• See parameter 8103 REFERENCE STEP 1.