BENSHAW RSi H2 Series - PID Basic Operation

PID Control
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890053-00-02
6.2 PID Basic Operation
PID operates by controlling the output frequency of the inverter in automated process control
systems to maintain speed, pressure, flow, or temperature.
PID Basic Operation Setting Details
Code
Description
PID-01
PID Sel
Set to ‘1 (Yes)’ to enable PID control and use functions for the process PID.
PID-03
PID Output
Displays the existing output value of the PID controller. The unit, gain, and
scale that were set in the PID group are applied on the display.
PID-04
PID Ref Value
Displays the existing reference value set for the PID controller. The unit, gain,
and scale that were set in the PID group are applied on the display.
PID-05
PID Fdb Value
Displays the latest feedback value as input to the PID controller. The unit, gain,
and scale that were set in the PID group are applied on the display.
PID-06
PID Err Value
Displays the difference between the existing reference and the feedback (error
value). The unit, gain, and scale that were set in the PID group are applied on
the display.
PID-10
PID Ref 1 Src
Selects the reference input (Setpoint source) for the PID control. The default
setting is to enter the setpoint at the Keypad, see PID-11 although other
sources may be used. The setpoint source cannot be set to the same source
as the PID feedback source (PID-20, PID Fdb Source).
Setting
Function
0
Keypad
Keypad
1
V1
-10-10 V input voltage terminal
3
V2
I2 analog input terminalWhen the analog voltage/current
input terminal selection switch (SW4) at the terminal block is
set to I (current), input 0-20 mA current. If it is set to V
(voltage), input 0–10 V.
4
I2
5
Int. 485
RS-485 input terminal
7
FieldBus
Communication command via a communication option card
Note
• Normal PID output (PID OUT) is bipolar and is limited by PID-30 (PID Limit Hi) and PID- 31
(PID Limit Lo) settings. DRV-20 (MaxFreq) value equals a 100% of PID OUT.
• The following are the variables used in PID operation, and how they are calculated:
- Unit MAX = PID Unit 100% (PID-53)
- Unit Min = (2xPID Unit 0% (PID-52)–PID Unit 100%)
- Unit Default = (PID Unit 100%-PID Unit 0%)/2
- Unit Band = Unit 100%-Unit 0%
• PID control may be utilized for the following operations:
Pre-PID/Soft fill, Auxiliary PID reference compensation, Flow compensation, Pipe
breakage detection.
• During a PID operation, the PID output becomes the frequency reference. The inverter
accelerates or decelerates to the frequency reference based on the Acc/Dec times.