Baker Hughes Masoneilan SVI II AP, Быстрый старт

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Setting Aggressiveness While the SVI II AP DTM and the DD allow you to set Aggressive-
ness, 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 SVI II AP 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 influ-
ences 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.
© 2018 Baker Hughes, a GE company, LLC. All rights reserved
. Masoneilan SVI II AP Digital Positioner Quick Start Guide
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Notes on Aggressiveness