CVGF Water Cooled Centrifugal Chillers January 2010
CVGF Key Features 2 stage centrifugal compressor Semi-hermetic compressor R134a refrigerant Falling film evaporator Economizer cycle NEW Tracer Adaptiview control module Unit mounted starter in 400V/50Hz : Star-delta or solid state 2
Benefits of a 2 stage compressor Wider range of unloading capability More surge resistant More efficient when combined w/ an economizer cycle 3
CVGF Compressor Design Motor Shaft Motor Housing Motor Rotor Motor Terminals Discharge Volute Bull Gear Pinion Motor Stator Oil tank including: -Pump 4 Suction Cover -Heaters -Filter
CVGF Compressor Design Motor speed: 3560 rpm in 60Hz 2970 rpm in 50Hz Bearings Gear Set Oil tank w/ pump, filter & heaters integrated in compressor casing 5 Impeller speed: Compressor family 500 : 10400 rpm 700 : 9605 rpm 1000: 7300 rpm
CVGF Motor Design Motor windings cooled by liquid refrigerant Voltages available 380/400/415V/50Hz 3300V/50Hz (not all sizes) 6600V/50Hz (not all sizes) 6
CVGF Motor Cooling System Condenser Motor No heat rejected in the equipment room like w/ air cooled motors Condenser Sump Filter F Liquid Refigerant Fixed Orifice No external piping needed like w/ water cooled motors Fixed Orifice Economizer Cpr 2nd Stage Evap 7
Benefits of a semi-hermetic compressor Motor cooled by liquid refg : windings operate at a lower T Motor heat not rejected into the equipment room : minimum 5% of kw input No maintenance on the shaft o-ring and no refg leak at the compressor shaft 8
Centrifugal Compressors: Range of Stability Comparison Compressor Characteristics define Chillers ability to Perform 35-55% 100% 10-25% 100% Head ( P) SURGE 18 C 13 C 24 C 30 C Head ( P) SURGE 24 C 18 C 13 C 30 C Capacity (kw) Capacity (kw) Single-Stage Double-Stage Design Point 9 Insert A double Footerstage compressor has a wider unloading capability
Impeller Dynamics V r α refrig flow rate V t α rpm diameter V t tangential velocity LIFT R resultant velocity diameter LOAD compressor work refrigerant flow rate V r radial velocity 10 rotational speed
Compressor Response to Load Decrease V t R V t R 15 C 11 C 500 Tons 1760 kw V r 250 Tons 880 kw V r 4920 CFM (2.32 m 3 /s) 2670 CFM (1.26 m 3 /s) full load part load 11
Benefits of CVGF 2 stage refigeration cycle Increased cooling capacity Higher overall efficiency With reduced refrigerant charge 12
Refrigerant Cycle : 2 stage compressor 35 C Extra cooling 30 C Gas Liquid and Gas 7 C 7 C 12 C 13 Insert The Footer economizer cycle increases the cooling effect in evaporator
Falling Film Evaporator Vapor refrigerant Liquid refrigerant Liquid distributor Orifice system Chilled water Tube bundle Benefits of Falling Film Evaporator: - reduced refrigerant charge - higher heat transfer 14
2 Stage Economizer Refrigerant vapor to second stage of compression Orifice Liquid refrigerant from condenser Liquid refrigerant to evaporator 15 Extra cooling
CVGF Optimized Oil Management System Fully integrated oil management system Efficient oil T control and return 16
CVGF Oil Cooling System Condenser Liquid refrigerant Hot oil Oil sump & pump Benefits Oil cooling integrated in overall efficiency of the chiller No external piping needed at jobsite for oil cooling Efficient and accurate oil T control Cold oil Oil cooler : Brazed Plate HX 17
CVGF Oil Return System Benefits The small qty of oil leaving the compressor is recovered at the bottom of the EVP Very limited qty of oil circulating in the heat exchangers >> low impact on heat transfer Refrigerant vapor 18 99% refrigerant + 1% Oil
19 CVGF Advanced Control
Tracer Adaptiview: Technical Features Easy-to-use 12 inch color, touch panel display Intuitive user interface Active & historic alarms Standard & customizable reports Standard & customizable graphs Advanced Adaptive Control technology embedded within the Tracer UC800 controller 20 Insert The Footer centrifugal chiller has never been so easy to use and manage
Technical Features: Interface Screen Chiller Status Area A G H Main Display Area/Home Screen Main Menu Area B C D E F Log Sheet ASHRAE Chiller Log About This Chiller Chiller Operating Modes Purge Operating Modes Improves Operator Productivity A B C At-a-Glance status D Graphs Intuitive navigation E Security levels Reports F 24 selectable languages 21 Insert An Intuitive/Easy Footer to Read Display to Enhance Operator Productivity G H Adjustable viewing angle Water resistant
Technical Features: Tracer UC800 Adaptive Control Algorithm Keeps chiller running under normal or extreme conditions Variable Flow Compensation Compatible with Tracer Chiller Plant Control Open Protocols MODBUS RTU BACnet LONTalk 22 Insert Different Footer Communication Protocols available
UC800 Technical Features UC800 Detached Display Din rail mounting USB service port Smaller footprint Large Color Display Protocol Support LONtalk Comm4 MODBUS Slave BACnet MSTP Service Tool Tracer TU (Basic/Advanced) Processor 240Meg Hz (8X) 23
Adaptive Control : ensures chilled water production even in duty conditions close to the limit Trip Point Temperature Traditional Chiller Shut-off TRANE Adaptive Control Time The controllers internal algorithms enables corrective actions to be taken that keeps the chiller safely on-line make cold water where other chiller would trip off. 24 Insert Keep Footer the Chiller in Operation as much as possible
Tracer Adaptiview: Benefits summary Improves operator productivity Guarantee of continuous operation by utilizing industry-best Adaptive Control algorithms Optimize chiller operation Easier integration in Building Automation System thanks to open protocol flexibility 25 Insert An optimized Footer controller supporting user friendliness and ease of integration
CVGF Starters Various types of starters available: Mounted or not Low and Medium voltage 26
CVGF Starters Type of Starters available 380, 400, 415 V/50/3 3300, 6600 V/50/3 Starter type Unit mounted Remote Customer Supplied Starter type Remote Customer Supplied Star-Delta Closed transition Solid state x x x x x x Across the Line Auto transformer x x x x Primary Reactor x x 27
CVGF Low Voltage Starters Inrush Current Starter Type %LRA Advantages Star-Delta Solid State 33 45 Equal reduction of torque & inrush current Price competitive Gradual inrush/ramp up No spike at transition Price slightly higher than Y- Disadvantages Only applicable up to 660 volts Spike at transition Higher level of service expense than Y- Higher inrush current then Y- Starting harmonics may be an issue Typical starting curves % LRA 28 Time (sec)
CVGF Medium Voltage Starters Inrush Current Starter Type %LRA Advantages Across-the-Line 100 Very price competitive Least Complex Lowest maintenance Disadvantages Draws highest inrush current at startup Primary Reactor 65 Good compromise between first cost and inrush current reduction More expensive than Across-the-Line Larger than Across-the Line Autotransformer 45 Almost equal reduction of torque and inrush current Lowest inrush current Most expensive Larger than Across-the Line Typical starting curves % LRA 29 Time (sec)
30 Good Sales!