Despatch MIC 1422

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APPENDIX C: RaPID CONTROL FEATURE
The RaPID (Response - assisted PID) feature offers dramatic improvements in control quality
compared with conventional PID techniques. It responds much more effectively than PID
techniques to load conditions. With this feature, the instrument's response at start-up, during
setpoint changes and during disturbances shows considerably reduced overshoot and much
more shorter settling times (see below).
RaPID works best with well-tuned terms. It is therefore recommended, on newly installed
instruments, that the Pre-Tune facility is run before RAP[D is engaged.
Note: If Pre-Tune and RaPID are both engaged, Pre-Tune will run first. Once Pre-Tune (a
single shot process) is automatically disengaged, RaPID will operate automatically.