© 2021 Baker Hughes Company. All rights reserved. Masoneilan SVi1000 Positioner Quick Start Guide | 37
Notes on Aggressiveness
Setting
Aggressiveness
While the SVi1000 DTM and the DD allow you to set
Aggressiveness, the pushbuttons do not. In all three methods,
however, the Aggressiveness value is inherited from any previously
performed tuning (Autotune or manual). Once Aggressiveness, and
other tuning values are determined, they are stored in NVRAM.
The SVi1000 provides a user define Aggressiveness Level for
auto-tuning, the allowable range varies from -9 to +9 where 0
(Zero) is consider normal tuning. The Aggressiveness Level
influences stroking speed and over-shoot. A negative value will
SLOW stroking speed and help minimized over-shoot. A positive
value will INCREASE stroking speed and may add some over-
shoot. The recommended values for Aggressiveness is 0 for
control valves without volume boosters.
In applications with volume boosters and/or quick exhaust valves
are used the Aggressiveness Level is not as influential. For Auto-
tuning it is usually between 0 and 3. Reduce the volume boosters
sensitivity by opening the integral bypass needle valve about 1 to 2
turns. Use caution when adjusting the needle valve so as to not to
damage the seat, close gently to seat and then open 1 or 2 turns.
Aggressiveness
Dynamic
Lower values of aggressiveness lead to lower PID values and
slower response and less overshoot.
Higher values lead to higher PID values and quicker response and
more overshoot.
Once you have a preferred aggressiveness and you tune once, all
future autotunes automatically use that same value, until user-
changed.
