LSIS 6731001500, User Manual

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Learning Advanced Features
5.12 Flow Compensation
In a system with a pipeline, longer pipes and higher flow rate cause greater pressure loss. A flow
compensation operation can compensate for pressure loss by increasing the volume of the PID
reference.
Group Code Name LCD Display Parameter Setting Setting Range Unit
AP1
30
Flow Comp
function options
Flow Comp Sel -
0 No
-
1 Yes
31
Max Comp
amount Max Comp
Value
- 0–Unit Band -
Flow Compensation Setting Details
Code Description
AP1-30 Flow
Comp Sel
Sets the Flow Compensation function options.
AP1-31 Max
Comp Value Sets the maximum compensation volume. This function is based on a PID
operation. The volum
e
is given the same unit used for the PID reference.
Longer pipes cause the actual pressure to decrease, which in turn increases the difference
between the pressure reference and the actual pressure. When the pipe lengths are equal in two
different systems, more pressure loss is caused in the system with greater flow. This explains the
pressure difference between (A) and (B) in the figure (when the flows are different). To compensate
for the pressure loss above, the value of AP1-31 is set to the maximum volume of compensation
when the inverter has the maximum frequency, and adds to the PID reference after calculating
compensation volume based on the output frequency.
The final PID reference=PID-11+Compensation amount, and compensation amount is shown