AEM 30-6905 Universal Programmable EMS-4 - Manual (Page 223)

Page 223 of 279 EMS-4 Install and Tuning Guide_Rev 1.6
Description: Sets the maximum feedback correction allowed in the positive duty direction when
using P+I control only. Used to set correction limits and help stabilize boost. This function can
help prevent overshooting.
Boost FB -Limit
Units: % Duty Cycle
Description: Sets the maximum feedback correction allowed in the negative duty
direction when using P+I control only. Used to set correction limits and help stabilize
boost. This function can help prevent overshooting.
Boost FB Int Gain
Units: Time Constant
Description: Integral control is implemented through the introduction of an integrator.
Integral control is used to provide the required accuracy for the control system. This
is used to fine tune the boost control at the target boost once the proportional has
acted in getting close to the target. Note: start tuning the boost control feedback with
this option at zero, until the proportional has the boost close to the target, then step
this in slowly until the target boost is achieved. This value should be a negative
value.
Boost FB Pro Gain
Units: Gain Multiplier
Description: Proportional control is a pure gain adjustment acting on the error signal
to provide the driving input. It is used to adjust the speed of the system and reach the
target boost quickly. The advantage of a proportional-only control is its simplicity. If
boost offsets can be tolerated, the use of a proportional controller may be optimal.
However, it will not eliminate the steady-state error that occurs after a set-point
change or a sustained load disturbance. Note: When tuning the boost control and
overshoot occurs, lower this value. If undershooting the target boost, raise this value.
This value should be a negative value. When the Boost FB On Error Control is
OFF and the Boost Error Duty table is not used, proportional and integral control is
applicable.
Boost Switch Input
Units: Switch Input
Description: Optional alternative boost level controlled from a switch input. The new
target should be set in the Boost Switch Target option. Used to enable both high
and low boost settings via a flip of a switch.
Boost Switch Target
Units: Engine Load
Description: This new boost target activates when using the Boost Switch Input
option. Used to enable both high and low boost settings via a flip of a switch.
Boost W/G Frequency
Units: Hz
Description: Specific frequency for the pulsewidth boost solenoid. If the boost
solenoid is excessively noisy and/or slow to respond, the frequency should be
changed. Note: Most boost solenoids make some noise.
Boost WG Invert