Trane Centrifugal Water Chillers CVGF - Manual (Page 8)

Tracer AdaptiView TM Controller
Today's centrifugal chillers offer predictive controls that anticipate and compensate for load
changes. Other control strategies made possible with the Tracer AdaptiView TM controls are:
Feedforward Adaptive Control
Feedforward is an open-loop, predictive control strategy designed to anticipate and compensate
for load changes. It uses evaporator entering-water temperature as an indication of load change.
This allows the controller to respond faster and maintain stable leaving-water temperatures.
Soft Loading
The chiller controller uses soft loading except during manual operation. Large adjustments
due to load or setpoint changes are made gradually, preventing the compressor from cycling
unnecessarily. It does this by internally fi ltering the setpoints to avoid reaching the differential-to-
stop or the current limit. Soft loading applies to the leaving chilled-water temperature and current-
limit setpoints.
Multi-Objective Limit Arbitration
There are many objectives that the controller must meet, but it cannot satisfy more than one
objective at a time. Typically, the controller’s primary objective is to maintain the evaporator leaving-
water temperature.
Whenever the controller senses that it can no longer meet its primary objective without triggering
a protective shutdown, it focuses on the most critical secondary objective. When the secondary
objective is no longer critical, the controller reverts to its primary objective.
Fast Restart
The controller allows the CenTravac chiller to restart during the postlube process. If the chiller shuts
down on a nonlatching diagnostic, the diagnostic has 30–60 seconds to clear itself and initiate a
fast restart. This includes momentary power losses.
Building Automation and Chiller Plant Control
Trane Tracer Summit TM building automation systems
include pre-engineered and fl exible control for
chiller plants. It can control the operation of the
complete installation: chillers, pumps, cooling
towers, isolating valves, air handlers and terminal
units.Trane can undertake full responsibility for an
optimized automation and energy management
for the entire chiller plant.
The main functions are:
• Chiller sequencing: equalizes the number of
running hours of the chillers. Different control
strategies are available depending on the
confi guration of the installation.
• Control of the auxiliaries: includes input/output
modules to control the operation of the various
auxiliary equipments (water pumps, valves,
cooling towers, etc.)
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Features and Benefi ts
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