Trane CVGF User manual

Centrifugal
Water Chillers
Model CVGF
Water-Cooled Hermetic Centrifugal
Refrigeration Capacities from
400 to 1000 Tons (1400〜3510 kW)
50 and 60 Hz
October 2008 CTV-PRC001-E4

Introducing Trane’s Model CVGF Centrifugal Water Chiller
Introduction
The basic gear driven centrifugal water chiller design was introduced in 1976 and has been proven
in thousands of installations. Trane continues to deliver its reliability and energy fitness commitment
on its newest line of gear-drive centrifugal water chillers, the Model CVGF. The major advantages of
the Model CVGF are:
• High reliability
• Low sound levels
• Compact size
• High efficiency at a competitive market price
• Designed to use environmentally responsible HFC-134a refrigerant
The Model CVGF chiller is ideal for office, hospital, school, hotel, retail store and industrial
buildings. TheTrane centrifugal chiller line offers hundreds of individual evaporator-condenser-
compressor combination selections, permitting precise tailoring of the machine capacity to
system requirements. Machine selections can be computer optimized to provide low first cost,
low operating cost, or other criteria important for a particular selection. Centrifugal Water Chiller
computer selection program is certified in accordance with ARI Standard 550/590. Trane Sales
Engineers are available to assist in selecting the optimum machine to satisfy the particular project
requirements.
Turn to the Model CVGF for energy efficiency provided by the two stage, gear drive centrifugal
water chillers with economizers. The Trane Model CVGF is your choice for energy fit operation year
after year.
Introduction
© 2008 Trane, All rights reserved CTV-PRC001-E4

Introduction …………………………………………………………………………2
Features and Benefits ……………………………………………………………9
Application Considerations ……………………………………………………10
General Data ………………………………………………………………………12
Jobsite Connections ……………………………………………………………13
Controls ……………………………………………………………………………17
Physical Dimensions ……………………………………………………………19
Mechanical Specifications ………………………………………………………23
Conversion Table …………………………………………………………………27
Contents
3
CTV-PRC001-E4

Standard CVGF Features
The following features are provided as standard with all Trane Model CVGFchillers:
• Hermetic two-stage centrifugal compressor-motor assembly with integral lubrication system
and economizer cycle
• Evaporator and condenser assembly
• Prewired instrument and control panel
• Oil charge
• Integral oil heaters
• Isolation pads
• Wiring and oil system interconnection to main control panel
• Advance motor protection
• Two-stage gear drive with economized cycle for high efficiency and high reliability
• Liquid cooled hermetic induction motor; the motor operates at lower temperatures for longer
motor life
Optional Features
• Unit and remote wye-delta mounted starters
• Unit mounted, floor mounted, and wall mounted solid state starters.
• Across-the-line, Primary Reactor, and Auto Transformer Remote mounted starter for medium/
high voltage
• Marine waterboxes for evaporator and condenser
• Factory-applied thermal insulation
• One-inch deflection spring isolators for vibration-sensitive installations
• Refrigerant available from a local distributor
• Building automation systems (BAS) Interface
• Factory testing
Applications
• Comfort cooling
• Industrial process cooling
Patents
• Polygon drive for refrigeration compressor impellers
• Centrifugal compressor sump demister
• Internal oil filter
• Thermosiphonic oil cooler
• Compressor height and alignment adjustment
• Oil return using hot gas for motive force
• Centrifugal impeller assembly
• Internal oil filter
Orifice System
• Simplified orifice system with improved part load performance down to 20 percent part load
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Features and Benefits
CTV-PRC001-E4

Advanced Heat Transfer Surfaces
• Evaporator and condenser tubes use the latest heat transfer surfaces
• Less refrigerant needed due to advanced patented evaporator design
Compact Size
• Designed with the retrofit and replacement market in mind
• The 400 to 500 NTON sizes can fit through most double-width doors
• Small footprint of the CVGF chiller saves valuable equipment room space
Simple Installation
• Simplified piping; the only water piping required is for the evaporator and condenser
• Simple power connection
• Unit mounted starter eliminates additional jobsite labor requirements
Environmental Features and Benefits
Improved Efficiency:
• High Efficiency: 0.55 kW/Ton at ARI conditions
• Motor cooling vented to economizer cycle, efficiency advantage
• HFC-134 optimized inlet guide vanes and impellers for improved cycle efficiency using
computational fluid dynamics
Reduced Emissions:
• Over 30 percent joint reduction in compressor/motor assembly compared to previous designs
• Patented integral heaters imbedded into the compressor casting, no seals no leaks
• Beaded flat gasket technology instead of O-rings, lower susceptibility to developing leaks
• Minimal NPT pipe threads on chiller system, SAE O-ring boss fitting, lowerleak potential
• Oil sump internal to compressor/motor assembly with internal pump/motor; eliminates vent and
drain lines, leak prevention
• Patented internal oil filter prevents leaks and contamination from pipes; filter is isolated and easily
replaced
• Advanced evaporator design minimizes the refrigerant charge; a reduced charge reduces the
exposure to the environment in the event of a catastrophic charge loss
Additional Features and Benefits
• Patented polygon attachment instead of a keyed shaft, self-balancing
• Easy to replace motor terminals
• Motor/stator assembly is easily removed; speed assembly can be removed independent of the
high-speed assembly
• Rolling element bearings
• Hydrodynamic bearings
• Advanced evaporator design: no eliminator necessary with an advanced suction baffle design
• All metric fasteners
Features and Benefits
5
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Tracer AdaptiViewTM Control Operator Interface
Tracer AdaptiViewTM control is the unit-mounted operator interface with a touch sensitive 12/1"
display. The display presents information through an intuitive navigation system. Alternate
languages are also available for the control panel display.
Tracer AdaptiViewTM control receives information from and communicates information to the other
devices on the chiller’s communications link. Tracer AdaptiViewTM control performs the Leaving
Chilled Water Temperature and Limit Control algorithms.
• Data graphs
• Mode overrides
• Status (all subsystems) with animated graphics
• Auto/Stop commands
• 50 diagnostics
• ASHRAE chiller log
• Setpoint adjustment (daily user points)
Tracer AdaptiViewTM control can be connected to the service tool using a standard USB type cable.
The connections is located on the side of the control panel, along with a power outlet for a laptop
PC power supply.
6
a
h
be
f
cdij
g
aAt-a-glance status
On highly-readable color display showing key operating parameters of
major chiller components
bIntuitive navigation
Helps operators access data and alarms for quick and accurate
response and resolution
cReports
Summarize data for clear understanding and interpretation
dGraphs
Visualize trend data for troubleshooting and fine-tuning
eAdaptive controlTM
Algorithms built into Tracer AdaptiviewTM pre-empt chiller disruptions
during rapidly changing conditions
fOpen protocol flexibility
Bacnet, Lontalk, and Modbus with no gateways
gAdjustable viewing angle
For all operators in close quarters via ergonomic arm
hWater-resistant
To cleaning overspray; weather-resistant for outdoor mounting with
optional cover
i Security levels
Limit access to designated, qualified staff members
j24 selectable languages
Convert the Tracer AdaptiviewTM user-centered design for global
deployment including simplified chinese, traditional chinese, japanese,
korean, thai, etc.
Features and Benefits
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7
Features and Benefits
Tracer TU Interface
The Tracer chiller controller adds a level of sophistication better served by a PC application to improve
service technician effectiveness and minimize chiller downtime. Tracer AdaptiView™ control is intended
to serve only typical daily tasks. The portable PC-based service-tool software, Tracer TU™,
supports service and maintenance tasks.
Tracer TU serves as a common interface to all Trane chillers, and will customize itself
based on the properties of the chiller with which it is communicating. Thus, the service technician
learns only one service interface.
The panel bus is easy to troubleshoot using LED sensor verification. Only the defective device is
replaced. Tracer TU can communicate with individual devices or groups of devices.
All chiller status, machine configuration settings, customizable limits, and up to 100 active or
historic diagnostics are displayed through the service-tool software interface.
LEDs and their respective Tracer TU indicators visually confirm the availability of each connected
sensor, relay, and actuator.
Tracer TU is designed to run on a customer’s laptop, connected to the AdaptiView control panel
with a USB cable.
Hardware requirements for Tracer TU:
• CD-ROM
• 1 GB RAM
• 1024 x 768 resolution
• Ethernet 10/100 Lan card
• Windows® XP Pro or Vista
• Pentium IV or higher processor
• An available USB port (USB 2.0)
CTV-PRC001-E4

Tracer AdaptiViewTM Controller
Today's centrifugal chillers offer predictive controls that anticipate and compensate for load
changes. Other control strategies made possible with the Tracer AdaptiViewTM 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 filtering 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 SummitTM building automation systems
include pre-engineered and flexible 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
configuration 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 Benefits
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• Time of day scheduling: allows the end user to define the occupancy period, i.e. time of the
day, holiday periods and exception schedules.
• Optimization of the start/stop time of the installation: based on the programmed schedule
of occupancy and on the historical temperature records, Tracer SummitTM calculates the optimal
start/stop time of the installation to get the best compromise between energy savings and
comfort of the occupants.
• Soft loading: the soft loading function minimizes the number of chillers that are operated to
satisfy a large chilled-water-loop pull down, thus preventing an overshoot of the actual capacity
required. Unnecessary starts are avoided and the peak current demand is lowered.
• Communication capabilities: local, through a PC workstation keyboard Tracer SummitTM
can be programmed to send messages to local or remote workstations and or a pager in the
following cases:
—Analog parameter exceeding a programmed value.
—Maintenance warning.
—Component failure alarm.
—Critical alarm messages. In this latter case, the message is displayed until the operator
acknowledges the receipt of the information. From the remote station it is also possible to
access and modify the chiller plant’s control parameters.
• Remote communication through a modem: As an option, a modem can be connected to
communicate the plant operation parameters through voice grade phone lines.
The remote terminal is a PC workstation equipped with a modem and software to display the
remote plant parameters.
Chiller-Tower Optimization
Tracer Summit™ chiller-tower optimization extends Adaptive Control™ to the rest of the chiller
plant. Chiller-tower optimization is a unique control algorithm for managing the chiller and cooling-
tower subsystem. It considers the chiller load and real-time ambient conditions, then optimizes the
tower setpoint temperature to maximize the efficiency of the subsystem.
Integrated Comfort™ System (ICS)
The onboard Tracer chiller controller is designed to be able to communicate with a wide range of
building automation systems. To take full advantage of the capabilities of the chiller, incorporate
your chiller into a Tracer Summit building automation system.
But the benefits do not stop at the chiller plant. At Trane, we realize that all energy used in your
cooling system is important. That is why we worked closely with other equipment manufacturers
to predict the energy required by the entire system. We used this information to create patented
control logic for optimizing the HVAC system efficiency.
The building owner’s challenge is to tie components and applications expertise into a single
reliable system that provides maximum comfort, control and efficiency. Trane’s Integrated-Comfort
™ Systems (ICS) are a concept that combines system components, controls and engineering
applications expertise into a single, logical and efficient system. These advanced controls are fully
commissioned and available on every piece of Trane equipment, from the largest chiller to the
smallest VAV box. As a manufacturer, only Trane offers this universe of equipment, controls and
factory installation and verification.
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Features and Benefits
CTV-PRC001-E4

Two-Stage Compressor Widens the Application Range
Why Centrifugal Compressors Surge
Centrifugal compressors produce their pressure differential
(head) by converting the kinetic energy of the gas leaving
the impeller into static pressure. The velocity of this gas is
the result of two components:
• The radial velocity component Vr, which is directly
proportional to the refrigerant gas flow Q.
• The tangential velocity component Vt,which is a function of
both impeller diameter D and the rotational speed rpm.
The length of the resultant vector V is proportional to the
kinetic energy available for conversion to static pressure
in the volute. Consequently, for a given compressor, Vtis
fixed and Vrvaries with the cooling load. With the chiller
unloading, the pressure differential between evaporator and
condenser decreases. The compressor matches the new load and the lower “head” by closing the
inlet guide vanes.
This reduces the gas flow it draws in and modifies its direction. Component Vrdecreases
accordingly, the vector diagram shifts and at some point, the balance of forces breaks down.
As pressurized gas rushes backwards through the impeller, the pressure in the gas passages
falls, allowing the compressor to restore the balance of forces. If the process repeats itself, the
compressor is said to surge.
Two-Stage Compressors Surge Less and Later
To produce the same head as a single-stage compressor, two-stage machines use two small
diameter impellers. Component Vtis the same as on each stage, though Vris the same as on a
single-stage compressor. This results in a better balance of forces at low loads and produces a
machine with a wider unloading capability.
In Trane centrifugal chillers, gas prerotation vanes ahead of the compression stage improve impeller
aerodynamic efficiency, resulting in smoother unloading and reducing power consumption.
The curves show that two-stage compressors surge less and later than single-stage machines.
Intersection point B, when the load line meets the surge area, corresponds to a higher part load
for the single-stage compressor than would be the case with a two-stage compressor. Two stage
machines, therefore, have a wider range of applications.
1 - Load Line
2 - Surge Line
3 - A
4 - B
5 - 40%
6 - 90° Vanes
7 - 100%
8 - Compressor Head
9 - Refrigerant Gas Flow
1 - Vr= f (Q)
2 - Vt= f (D, RPM)
3 - V = Resultant
4 - rpm
5 - D
6 - Q
Typical single-stage compressor
performance curve
1 - Load Line
2 - Surge Line
3 - A
4 - B
5 - 20%
6 - 90°
7 - 80°
8 - 70° Vanes
9 - 100%
10 - Compressor Head
11 - Refrigerant Gas Flow
Typical two-stage compressor
performance curve
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Features and Benefits
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