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D-EIMWC00908-16EN - 38/52 

Operation 

 

 

Capacity Control System  

The capacity of the chiller is controlled by:  
 
1.  Staging the compressors on and off;  
2.  By  adjusting  the  capacity  of  each  compressor  by  opening  or  closing  the  inlet  vanes  to  control  the  quantity  of 

refrigerant entering the impeller; and,  

3.  Varying compressor speed to change capacity.  
 
The  speed  control  and  vane  control  work  in  conjunction.  As  load  decreases,  compressor  speed  is  reduced  as  low  as 
possible but above the point where stall might begin. If further capacity reduction is required, the guide vanes will close to 
whatever position is required to match the compressor capacity to the load.  

Surge and Stall  

Stall  and  surge  are  a  characteristic  of  all  centrifugal  compressors.  These  conditions  can  occur  at  low  load  conditions 
when the operating point moves to the left of the compressor surge line on the performance curve.  
In  surge,  the  discharge  gas  alternately  flows  backward  and  forward  through  the  impeller  reversing  about  every  two 
seconds. Increased noise, vibration and heat occur and motor current varies widely. Surge can damage a compressor. 
The compressors are equipped with safety features that help prevent surge from occurring.  
Another instability is stall or incipient surge, which occurs a little to the left, or before, the surge condition. Discharge gas 
in the diffuser forms rotating stall pockets or cells. The compressor sound level will change and the impeller starts to heat 
up. Motor current remains steady.  

Normal Unit Startup/Shutdown  

Startup  and  shutdown,  other  than  seasonal  shutdowns,  are  considered  to  be  normal  operation  and  the  following 
procedures apply (assuming that the equipment room temperature are above freezing). The procedures would be used 
for a weekend shutdown, for example.  
Note that the chiller is part of an entire building heating and cooling system that are usually unique to a particular site. 
For  example,  the  chilled  water  loop  and  chilled  water  pump  can  also  be  used  for  heating  and  therefore  must  be 
operational year-around. The cooling tower can be used for other equipment besides the chiller and may have to remain 
functional  even  though  the  chiller  is  not.  The  following  procedures,  therefore,  must  take  the  peculiarities  of  the  entire 
system into account.  

Shutdown  

If  the  unit  is  to  be  secured  for  several  days,  and  is  already off  due  to  lack  of load,  the  UNIT  switch  in  the  Unit  Control 
Panel  (and  the  remote  Start/Stop  switch,  if  used)  should  be  placed  in  the  OFF  position.  If  the  chilled  water  pump  and 
cooling  tower  are  not  required  for  other  purposes,  they  too  can  be  turned  off.  If  the  pumps  are  controlled  by  the  unit 
controller, they will shut down after the compressors.  
If the chiller is running, the chilled water and condenser water pumps must remain on until the compressors are stopped. 
This  is  true  regardless  of  how  the  unit  is  turned  off,  whether  by  the  local  switches  or  through  a  remote  signal.  The 
compressors  go  through  a  short  shutdown  sequence,  shutting  guide  vanes  and  performing  other  functions,  before  it 
finally stops. The pumps must remain on during this shutdown period.  
Once  the  compressors  and  pumps  have  stopped,  no  further  action  is  required  other  than  opening  disconnects,  if  so 
desired.  

Startup  

Any disconnects that were opened must be closed. The  chilled water pump and cooling tower should be turned on and 
flow verified. The chiller can then be started by placing the UNIT switch (and the remote Start/Stop switch, if used) in the 
ON position. There is no lube warm-up period required. The compressors go through a starting sequence and may not 
start  immediately.  Once  started,  it  is  prudent  to  observe  unit  operation  on  the  operator  interface  screen  for  several 
minutes to check for normal functioning.  

Start/Stop Switching  

There  are  four  ways  to  start/stop  the  chiller.  Three  are  selected  in  SETPOINT\  MODE\SP3,  the  fourth  way  is  through 
panel-mounted switches:  

 

1. 

Operator Interface Panel, 

(LOCAL) Home Screen 1 has AUTO and STOP buttons that are only active when the unit 

is in "LOCAL CONTROL". This prevents the unit from being accidentally started or stopped when it is under control 
from  a  remote  switch  or  BAS.  When  these  buttons  are  pressed,  the  unit  will  cycle  through  its  normal  starting  or 
stopping  sequence,  both  compressors  will  be  stopped  and  normal  dual  compressor  starting  procedure  will  be  in 
effect.  

 

2.  Remote SWITCH, 

Selecting SWITCH in SP3 will put the unit under the control of a remote switch that must be wired 

into the control (see Field Wiring Diagram)

 

Содержание C10FZXS

Страница 1: ...nual Installation Operation and Maintenance Manual Frictionless Centrifugal Chiller EWWD320 C10FZXS Cooling capacity from 114 to 1048 kW Refrigerant R 134a Original Instructions Installation Operation...

Страница 2: ...assume no liability whatsoever for any direct or indirect damage in the widest sense of the term ensuing from or connected with the use and or interpretation of this Manual The entire content is prote...

Страница 3: ...nel for 1 and 2 compressors unit 8 9 Label Identification 1 Non flammable gas symbol 6 Cable tightening warning 2 Manufacturer s logo 7 Water circuit filling warning 3 Gas type 8 Lifting instructions...

Страница 4: ...22 Field Wiring Diagram Notes 24 Control Wiring 24 VFD Line Harmonics 24 Current Harmonics 24 Voltage Harmonics 24 Line Reactors 24 Harmonic Filter 25 EMI Electro Magnetic Interference and RFI Radio F...

Страница 5: ...gerant used 47 Disposal 47 Index of tables Table 1 Acceptable water quality limits 14 Table 2 Electrical data 21 Table 3 Pwer wiring recommended fuses and cables 22 Table 4 Electrical data 26 Table 5...

Страница 6: ...automatically controlled fluid chilling units featuring oil free magnetic bearing compressors Each unit is completely assembled and factory tested before shipment Magnitude chillers are equipped with...

Страница 7: ...eat recovery Refrigerant D R 134a P R 407c Q R 410a Capacity class in kW Cooling Always 3 digit code Model series Letter A B major modification Inverter Non inverter Z Inverter Efficiency level S Stan...

Страница 8: ...pressure drop 4 kPa 24 3 24 5 28 2 23 7 25 3 29 3 Insulation material None available as an option Compressor Type Frictioneless Centrifugal Compressor Oil free Sound level Sound Power Cooling dB A 89...

Страница 9: ...line ATTENTION Storing in condensing atmosphere may damage the electronic components Operation ATTENTION Daikin EWWD FZ chillers are suitable for stationary installations only For any moving or marine...

Страница 10: ...D EIMWC00908 16EN 10 52 Figure 1 Operating limits Other limits are Maximum startup evaporator inlet fluid temperature 32 C Maximum non operating inlet fluid temperature 38 C...

Страница 11: ...jury Avoid introducing solid objects into the water pipes while the machine is connected to the system A mechanical filter must be installed on the water pipe connected to the heat exchanger inlet The...

Страница 12: ...ground prepare a strong cement base that is at least 250 mm wider and longer than the machine Also this base must be strong enough to support the weight of the machine as stated in the technical spec...

Страница 13: ...em during service 3 Manual or automatic air venting device at the system s highest point drain device at the system s lowest point Neither the evaporator nor the heat recovery device must be positione...

Страница 14: ...quipment caused by failure to treat water or by improperly treated water Figure 3 Water piping connection for evaporator and condenser Legend translation Gauge Gauge Flexible connector Flexible connec...

Страница 15: ...ult in damage to some of the machine s components Damage caused by freezing is not covered by the warranty Loss of flow protection All chiller are equipped with redundant differential pressure switche...

Страница 16: ...D EIMWC00908 16EN 16 52 Figure 4 Evaporator pressure drop...

Страница 17: ...D EIMWC00908 16EN 17 52...

Страница 18: ...D EIMWC00908 16EN 18 52 Figure 5 Condenser pressure drop...

Страница 19: ...D EIMWC00908 16EN 19 52 Figure 4 and 5 legend Label Size Label Size A 320FZ D 640FZ B 430FZ E 860FZ C 520FZ F C10FZ...

Страница 20: ...e event of certain malfunctions ATTENTION This unit is designed for indoor installation Check that there is sufficient air circulation through the machine Possible damage from inhalation of refrigeran...

Страница 21: ...charged with high voltage for a short period of time The unit can be worked on again after it has been switched of for 10 minutes Please consult the compressor manual for further details CAUTION The...

Страница 22: ...ith copper wire and copper lugs only The table below is a reference only for dimensioning protection devices and wiring Due to different needs and local codes the customer may select different compone...

Страница 23: ...low Switch Remote Start Stop Mode Switch Analog Input Terminals Leaving Water Reset Demand Limit Evap GPM Condens GPM Digital Output Terminals Evap Water Pump 1 2 Condens Water Pump 1 2 Tower Stage 1...

Страница 24: ...supplied from a factory wired transformer located in the electrical box Control wiring must be of suitable size in accordance with local regulations VFD Line Harmonics Despite their many benefits car...

Страница 25: ...EMC directives in a compact efficient light weight design The high common mode and differential mode reduction in the critical 150kHz to 30MHz frequencies assures that potential interference from AC d...

Страница 26: ...t J11 the shield connects to GND the blue white wire to the connection and the white blue to the connection Note that Chiller B does not have or need an isolation board 5 Verify correct nodes on each...

Страница 27: ...nd the compressor with maximum hours will stop first and so on Units with higher numbers will stage on in sequence The Modes setpoints will do several different types of operation Normal Efficiency St...

Страница 28: ...stem to provide an opportunity for the chiller to sense a load change adjust to the change and stabilize As the expected load change becomes more rapid a greater water volume is needed The system wate...

Страница 29: ...tically when the start to start timer expires Transfer Back to Grid Power Proper transfer from stand by generator power back to grid power is essential to avoid compressor damage ATTENTION Stop the ch...

Страница 30: ...essors and compressed The high pressure refrigerant gas is sent to the condenser where flowing shell side the superheated refrigerant vapour cools down and starts to condense and then the liquid is su...

Страница 31: ...D EIMWC00908 16EN 31 52 Figure 9 Refrigeration cycle a Single compressor unit b Dual compressor unit...

Страница 32: ...ass Evaporator and condenser differential pressure switches Safety valve Valve Mechanical filter flare connection Check valve WOC Condenser leaving water centerature sensor WIC Condenser water inlet t...

Страница 33: ...r speed adjusts to changes in load and or condensing temperature As compressor speed reduces due to lower loads and or condensing temperatures energy consumption dramatically reduces Part load energy...

Страница 34: ...D EIMWC00908 16EN 34 52 Figure 12 Compressor overview...

Страница 35: ...ck disconnector switch terminals The power supply voltage must be the same as that on the nameplate Maximum allowed tolerance 10 Voltage unbalance between the three phases must not exceed 3 Fill the w...

Страница 36: ...uld cause malfunction of the control components and undesired triggering of the thermal protection devices along with a considerable reduction in the life of the contactors and electric motors Unbalan...

Страница 37: ...em operated and flow balanced to meet unit requirements Electrical Power leads connected to the unit power panel s All interlock wiring complete between control panel and complies with specifications...

Страница 38: ...the chiller is not The following procedures therefore must take the peculiarities of the entire system into account Shutdown If the unit is to be secured for several days and is already off due to la...

Страница 39: ...way 3 Open the compressor disconnect switch Set the manual COMPRESSOR and UNIT ON OFF switches in the Unit Control Panel to the OFF position 4 Check for corrosion and clean and paint rusted surfaces 5...

Страница 40: ...rheat low super cooling value Additionally a low level of liquid refrigerant inside the evaporator may be recognized In this case add R134a refrigerant only The system has been provided with a charge...

Страница 41: ...for units that run for a season of approximately 90 days year at seasonal start up It is important that during initial start up and periodically during operation routine verifications and checks are...

Страница 42: ...include all the weekly ones 2 The annual or early season activities include all weekly and monthly activities 3 Machine operating values should be read on a daily basis thus keeping high observation s...

Страница 43: ...t the rated conditions Note When the load or the cooling water temperature vary for example due to cooling tower fans starting stopping so does the subcooling and it requires several minutes to stabil...

Страница 44: ...etween 0 5 and 1 C 4 Check the subcooling value The subcooling value must be between 4 and 6 C a With reference to the above mentioned values the subcooling will be lower at 70 100 load and higher at...

Страница 45: ...is sensor is located on the evaporator inlet water connection and is used for monitoring the return water temperature Evaporator differential pressure switches Two sensors are located between the evap...

Страница 46: ...r Entering water temperature C _________ Condenser Pressure drop kPa _________ Condenser Water flow rate m 3 h _________ Refrigerant side measurements Compressors Compressor 1 Load _____ Compressor 2...

Страница 47: ...l power supply must be within the voltage limits and without voltage harmonics or sudden changes 5 The three phase power supply must not have un unbalance between phases exceeding 3 The machine must s...

Страница 48: ...gerant charge Factory Field h Greenhouse gas emission of the total refrigerant charge expressed as tonnes of CO2 equivalent m Refrigerant type n GWP Global Warming Potential p Unit serial number 2 The...

Страница 49: ...osal The unit is made of metal and plastic parts All these parts must be disposed of in accordance with the local regulations in terms of disposal Lead batteries must be collected and taken to specifi...

Страница 50: ...D EIMWC00908 16EN 50 52...

Страница 51: ...D EIMWC00908 16EN 51 52...

Страница 52: ...of its content and the products and services presented therein Specification are subject to change without prior notice Refer to the data communicated at the time of the order Daikin Applied Europe S...

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