If the 'I' gain is turned up too high, then the movement will constantly seek the
desired position, overshoot, and seek again. Unlike the oscillation that occurs
when the 'P' is set too high, the 'I' oscillation occurs at a low speed. Although
mildly amusing, it is rarely destructive. If the 'I' is adjusted too low, then the 'dead
band' around the desired position will be slightly wider.
E) Derivative (D) Gain (numeric value, slider, checkbox & output voltage
display)
This Numeric Value box and slider used to manually set the 'D' gain used by
the currently selected axis. If you don't want to use Derivative (D) Gain, just
uncheck the checkbox.
The 'D', or 'Derivative' gain is used in a PID ServoLoop to accelerate and
decelerate the actuator quickly to try to follow quickly changing command
positions more closely.
You can think of the 'D' gain as an accelerator pump in an automobile
carburetor. If you thrump on the accelerator pedal, the carburetor's accelerator
pump will send an extra bolus of gasoline down the throat of the carburetor to
help accelerate the car quickly.
The 'D' gain works in exactly the same way in a servo loop. You can see its
effect most clearly when performing a 'step' test, where you send commands to
the servo loop that step sharply between command values. The 'D' gain helps
the actuator accelerate more quickly at the beginning of a step.
With slightly slower steps, if the 'D' is set too high, then the movement will
start too quickly, overshoot the commanded position, and then slow down as the
'P' error takes over.
F) Tightness (numeric value & slider)
Available only after running the PID Wizard.
In industrial controls, you generally want the actuator to move as quickly and
accurately as possible. In entertainment applications, you may want the
movements to be slower and softer, or faster and stiffer, depending on your
application.
The 'Tightness' setting defaults to 50%. If you want the movement to be fast
and sharp, you can increase the 'Tightness'. If you want the movement to be
slower and 'softer', you can decrease the 'tightness' as needed. As the
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Br-EFB Manual / May 22, 2018 3:28 PM / page 57 of 142
