Midea LSBLG255/MZ Page 38 Technical & Service Manual Download

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MCAC-CTSM-2014-03 DX type water-cooled screw chiller (PCB Control)

2) Cooling stop

4. Sensors

1).Temperature sensors

The temperature sensors that unit use are all NTC thermistors, including chilled leaving water
temperature, chilled entering water temperature, discharged temperature, EXV suction temperature.

NO.

Name

Type

Remark

Chilled entering water temp.

NTC,10k@25

℃

Emerson

Chilled leaving water temp.

NTC,10k@25

℃

Emerson

EXV suction temp.

NTC,10k@25

℃

Carel

Lubrication oil temperature

NTC,10k@25

℃

Emerson

Thermistors

For PTC thermistors, resistances vary with various temperatures.



Location

Motor thermistor locates in the motor winding and is connected to the compressor protection module

which will cut off the main power when motor winding temperature exceeds

110 °C

. Water temperature

thermistors are installed in wells on chilled water inlet/outlet and cooling water inlet/outlet. Refer to the

electric control wiring diagram for detail connection information.

stop

Running time
is enough

Stand by

YES

Unload to 50% step

Unload to 25% step

Compressor off

Compressor 25%SV off

Cooling tower off
Cooing pump off

Chilled pump off

Summary of Contents for LSBLG255/MZ

Page 1: ...LSBLG MZ Model TechnicalServiceManual Water cooled Screw Chiller ...

Page 2: ...ntrol Flow Chart 34 2 Energy Adjustment 35 3 Start stop process 36 4 Sensors 37 5 Parts control 39 6 Operation Part 46 7 Safety protection 61 Ⅳ Electrical control 63 1 Electrical data 63 2 Electrical components introduction 63 3 Electrical Parts parameter setting 65 4 Field wiring 68 Ⅴ Installation 73 1 Unit installation 73 2 Water Pipeline System installation 76 3 Wiring installation 83 Ⅵ Commiss...

Page 3: ...ions on the certified drawings supplied with the unit Safety is only guaranteed if these instructions are carefully followed If this is not the case there is a risk of material deterioration and injuries to personnel Never cover any safety devices This applies to the relief valve s in the refrigerant circuit s Ensure that the valves are correctly installed before operating the unit The relief valv...

Page 4: ...eers working on the unit must be equipped with safety gloves glasses shoes and protective clothing 2 Never work on a unit that is still energized 3 Never work on any of the electrical components until the general power supply to the unit has been cut using the disconnect switch in the control box 4 If any maintenance operations are carried out on the unit lock the power supply circuit ahead of the...

Page 5: ...dations in unit and installation safety standards If a leak occurs or if the refrigerant becomes contaminated e g by a short circuit in a motor remove the complete charge using a recovery unit and store the refrigerant in mobile containers Repair the leak detected and recharge the circuit with the total R22 charge as indicated on the unit name plate Certain parts of the circuit can be isolated Onl...

Page 6: ...e it is running Be sure pressure is at 0 kPa before removing components or opening a circuit Do not attempt to repair or recondition any safety devices when corrosion or build up of foreign material rust dirt scale etc is found within the valve body or mechanism If necessary replace the device Do not install safety valves in series or backwards ATTENTION No part of the unit must be used as a walkw...

Page 7: ...0V 3N 50Hz 318 1 LSBLG400 MZ 380V 3N 50Hz 400 1 LSBLG485 MZ 380V 3N 50Hz 485 1 LSBLG630 MZ 380V 3N 50Hz 628 1 LSBLG860 MZ 380V 3N 50Hz 859 1 Dual heads LSBLG970 MZ 380V 3N 50Hz 970 2 LSBLG1060 MZ 380V 3N 50Hz 1057 2 LSBLG1260 MZ 380V 3N 50Hz 1256 2 LSBLG1490 MZ 380V 3N 50Hz 1487 2 LS B 255 M C LG LS Water chiller B Semi hermetic LG Screw type compressor 255 Nominal cooling capacity kW Design seque...

Page 8: ...MCAC CTSM 2014 03 DX type water cooled screw chiller PCB Control 7 3 External Appearance LSBLG255 MZ LSBLG860 MZ LSBLG970 MZ LSBLG1490 MZ ...

Page 9: ...ates most of the time Outstanding reliability Full factory testing of the unit with water hookup helps provides a trouble free start up Extensive quality control checks during testing means that each equipment protection and operating control is properly adjusted and operates correctly before it leaves the factory Transport simulation test in the laboratory on a vibrating table Factory installed o...

Page 10: ...re mesh to the electrical panel Refrigerant and lubrication oil are provided to the unit in the factory Only piping connection and power supply connection are required on the site Wide application range Water cooled screw chiller are widely applied in school hospital shopping mall office as well as the factory and manufacturing processing area ...

Page 11: ...150 150 130 160 320 260 Water flow m h 54 4 68 4 86 104 3 135 184 7 Pressure drop kPa 36 41 22 49 81 41 Max pressure MPa 1 1 1 1 1 1 Water inlet outlet pipe dia mm 80 80 100 125 125 150 Unit length mm 2800 2800 2860 3200 3430 3430 Unit width mm 1165 1165 1285 1300 1480 1610 Unit height mm 1350 1350 1420 1450 1600 1730 Shipping weight kg 1540 1870 2250 2610 2975 3780 Running weight kg 1840 2070 255...

Page 12: ...ontent L 360 320 460 430 Water flow m h 208 6 227 3 270 319 7 Pressure drop kPa 40 99 56 99 Max pressure MPa 1 1 1 1 Water inlet outlet pipe dia mm 150 150 200 200 Unit length mm 4100 4100 4450 4600 Unit width mm 1630 1740 1780 1810 Unit height mm 1680 1680 1730 1920 Shipping weight kg 4630 4870 5840 6490 Running weight kg 5080 5320 6340 7090 Safety protection device The following safety devices a...

Page 13: ...Z 3430 1610 1730 1800 1360 2120 400 300 200 DN150 DN150 Dual heads Chilled Water Outlet Chilled Water Inlet Cooling Water Outlet Cooling Water Inlet Model A B C D E F H J K Cooling Water In outlet Chilled Water In outlet LSBLG970 MZ 4100 1630 1680 1800 1440 2120 415 290 200 DN150 DN150 LSBLG1060 MZ 4100 1740 1680 1800 1440 2680 415 290 200 DN150 DN150 LSBLG1260 MZ 4450 1780 1730 2000 1540 3080 415...

Page 14: ...MCAC CTSM 2014 03 DX type water cooled screw chiller PCB Control 13 5 Refrigeration system For single head unit LSBLG255 630 MZ ...

Page 15: ...DX type water cooled screw chiller PCB Control MCAC CTSM 2014 03 14 For single head unit LSBLG860 MZ ...

Page 16: ...MCAC CTSM 2014 03 DX type water cooled screw chiller PCB Control 15 For dual heads unit LSBLG970 1260 MZ ...

Page 17: ...DX type water cooled screw chiller PCB Control MCAC CTSM 2014 03 16 For dual heads unit LSBLG1490 MZ ...

Page 18: ...w chiller PCB Control 17 6 Major System Components Major components of the unit 1 Single compressor parataxis type unit No Name 1 Controller 2 Pressure Gauge 3 Compressor 4 Evaporator 5 Safety Valve 6 Condenser 7 Expansion Valve 8 Emergency Stop ...

Page 19: ...ompressor that has the latest advanced 5 6 asymmetry dentiform semi hermetic screw rotors The rotors are processed by high precision CNC and each part is well proportioned and none gap matching which minimizes the friction resistance and clearance lost guarantees quiet running and good duration Compressors have a infinitely variable control down to 25 of its total capacity This control is made by ...

Page 20: ...low noise due to balance testing by special machine Comparing with normal screw rotor with 4 6 dentiform heat efficiency of the rotor with male and female rotor adopting 5 6 dentiform increase by 10 12 and energy saves by 25 the rotor also gained British and American patent The bearing of compressor is from SKF Sweden the long lifespan of which ensures screw type main unit to run continuously more...

Page 21: ...at the insulation joints Regularly check for possible presence of impurities e g silicon grains in the heat exchange fluids These impurities maybe the cause of the wear or corrosion by puncture Filter the heat exchange fluid check and carry out internal inspections as described in EN 378 2 In case of re testing please refer to the maximum operating pressure given on the unit nameplate The reports ...

Page 22: ... 2 7 Condenser Shell and tube operates with refrigerant in shell and water in tubes Replaceable water tubes are fabricated from integral finned cooper and mechanically bonded to steel tube sheets The condenser is GB151 1999 Chinese standard designed constructed inspected and stamped Water side working pressure is designed for 1 0MPa The condenser is used high efficient tubes to enhance its transfe...

Page 23: ...70 LSBLG320 MZ 38 55 71 48 68 88 LSBLG400 MZ 48 69 90 60 86 111 LSBLG485 MZ 58 83 108 74 104 134 LSBLG630 MZ 76 108 140 95 135 176 LSBLG860 MZ 104 148 192 129 184 239 LSBLG970 MZ 117 167 217 146 209 271 LSBLG1060 MZ 127 182 237 159 227 295 LSBLG1260 MZ 151 216 281 189 270 351 LSBLG1490 MZ 179 256 333 224 320 416 Pressure drop DX type Evaporator Pressure drop kPa Water flow m3 h 0 20 40 60 80 100 1...

Page 24: ... Water flow m3 h 0 20 40 60 80 100 120 140 160 50 150 250 350 LSBLG970 MZ LSBLG1060 MZ LSBLG1260 MZ LSBLG1490 MZ DX type Condenser 0 10 20 30 40 50 60 70 80 90 100 0 50 100 150 200 LSBLG255 MZ LSBLG320 MZ LSBLG400 MZ LSBLG485 MZ LSBLG630 MZ LSBLG860 MZ Pressure drop kPa Water flow m3 h ...

Page 25: ... water volume The tank itself must be internally baffled in order to ensure proper mixing of the liquid water or brine Water tank volume is large than 1 10 whole system water volume at least Refer to the examples below How to calculate minimum volume in pipeline system W QgT CP t W Minimum water volume kg Qg Total cooling heating capacity of the terminal kW T Thermal stability time requirement Tak...

Page 26: ... compressor nameplate The compressor recommended oil level are as follow Unit Model Compressor Model Oil level L Unit Model Compressor Model Oil level L LSBLG255 MZ RC 2 M255B 14 LSBLG860 MZ RC 2 M860B 28 LSBLG320 MZ RC 2 M320B 14 LSBLG970 MZ 2 RC 2 M485B 2 18 LSBLG400 MZ RC 2 M400B 15 LSBLG1060 MZ RC 2 M485B RC 2 M570B 18 23 LSBLG485 MZ RC 2 M485B 18 LSBLG1260 MZ 2 RC 2 M630B 2 23 LSBLG630 MZ RC ...

Page 27: ...tolerance 2 Power supply frequency Rating frequency 2 Evaporator max working pressure on water side 1 0MPa Compressor max start count 4 times h Environment quality High corrosive environment and high humidity should be avoided Drainage system The height of water drainage should not be higher than the base of the unit on the spot Normal operation ambient temperature 10 45 Storage and transport temp...

Page 28: ...ow 5 C freeze protection switch will work unit stop 2 If the temperature leaving the condenser is below 19 C the unit will stop and warning 3 Ambient temperatures During storage and transport of the LSBLG M units Including by container the minimum and maximum permissible temperatures is 20 C 50 C Changes water temperature curve in the operation ...

Page 29: ...8 09 497 90 80 83 492 08 82 32 479 67 85 22 15 00 561 75 75 93 549 81 78 56 543 83 79 84 531 47 82 62 525 10 84 06 511 96 87 07 Note The inlet outlet water temperature difference is 5 Chilled Water Outlet Temp Cooling Water Inlet Temp C 25 00 26 00 27 00 29 00 30 00 32 00 33 00 35 00 Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity P...

Page 30: ...00 706 60 96 33 691 58 99 67 684 06 101 29 668 52 104 82 660 51 106 64 643 97 110 47 LSBLG485 MZ Chilled Water Outlet Temp Cooling Water Inlet Temp C 25 00 26 00 27 00 29 00 30 00 32 00 33 00 35 00 Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power C kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW 5 00 446 08 87 93 441 28 89 40 4...

Page 31: ... 1109 36 141 66 1085 78 146 57 1073 98 148 95 1049 57 154 15 1036 99 156 82 1011 03 162 45 LSBLG860 MZ Chilled Water Outlet Temp Cooling Water Inlet Temp C 25 00 26 00 27 00 29 00 30 00 32 00 33 00 35 00 Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power C kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW 5 00 790 07 152 11 781 56 ...

Page 32: ...254 38 15 00 1713 51 226 65 1677 08 234 51 1658 86 238 33 1621 15 246 64 1601 73 250 91 1561 63 259 92 LSBLG1060 MZ Chilled Water Outlet Temp Cooling Water Inlet Temp C 25 00 26 00 27 00 29 00 30 00 32 00 33 00 35 00 Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power C kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW 5 00 972 18 1...

Page 33: ... 56 317 98 15 00 2218 72 283 32 2171 57 293 14 2147 96 297 91 2099 14 308 30 2073 99 313 64 2022 07 324 90 LSBLG1490 MZ Chilled Water Outlet Temp Cooling Water Inlet Temp C 25 00 26 00 27 00 29 00 30 00 32 00 33 00 35 00 Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power Capacity Power C kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW kW 5 00 1367...

Page 34: ... from frost crack 2 2 Vibration damper MHD series To avoid vibration and noise it must be used between base and foundation when install the unit 4 3 Remote control cabinet YCKZ P Can be installed in the control room Through the cable connected to the unit touch screen it can display all states information and complete all the operations of unit startup shutdown error confirm etc 1 4 Flange JB81 94...

Page 35: ...ng to input signal from HMI such as starting signal controller performs the logical operations and outputs signals These signals act on components time relay contactors and so on Phase Sequence Protector Miniature Circuit Breaker M Compressor Thermorelay Compressor Contactor Star Delta Start HMI Terminal for External Signal e g Temp Pressure Terminal for Output Action e g Solenoid Valve Main base ...

Page 36: ...hiller PCB Control 35 2 Energy Adjustment The unit adjust capacity by chilled water The control logic refers to the picture Energy adjustment is districted when starting high pressure is too high High pressure 19Bar 18Bar unloading Normal adjusting ...

Page 37: ...ES Clear failure Start on pump on Water flow switch protection Stop Clear failure YES NO Water temp is ok Oil heating time is enough Stop time is enough NO Stand by YES Compressor 25 SV on Compressor Y start Compressor 50 SV on 25 SV off Compressor 75 SV on 50 SV off Energy adjust Stand by unload loading Stop Water temp is ok NO ...

Page 38: ...ication oil temperature NTC 10k 25 Emerson Thermistors For PTC thermistors resistances vary with various temperatures Location Motor thermistor locates in the motor winding and is connected to the compressor protection module which will cut off the main power when motor winding temperature exceeds 110 C Water temperature thermistors are installed in wells on chilled water inlet outlet and cooling ...

Page 39: ...stor probe and well Tighten the screw to prevent thermistors from slipping out of the well To Service Compressor Motor Thermistors A thermistor is factory installed in each compressor Connections for the thermistors are located in the compressor wiring box 2 terminals are reserved for the thermistor S1 and S2 Motor temperature is measured by leads connected to S1 and S2 terminal The thermistors ar...

Page 40: ... down happens during operation and downtime is less than 3hrs no heating time delay is needed when unit restarts If it exceeds 3hrs 1h heating time is need If it exceeds 5hrs 2hrs heating time is need When cooling water inlet temperature 20 C real time value oil heating time for first startup is 4hrs If power down happens during operation and downtime is less than 1hrs no heating time delay is nee...

Page 41: ...of EXV controller cannot display and set parameter on unit only running status display If parameter needs to be displayed and set Interface should be changed LED Light Extinguish Flicker NET Can be connected to the network Not connected Communication failure OPEN Open the valve Disable the drive CLOSE Close the valve Disable the drive Activate the alarm Drive power The drive is not connected to po...

Page 42: ...ueue When the producer level under the rolling parameters the display shows the interface Esc To exit the programming maintenance producer and display mode set a parameter the exit without saving changes UP DOWN Display screen navigation Increase decrease the value 1 Display suction superheat 2 Display EXV opening 3 Relay output status 4 Alarm 5 Start of the protection 6 Control state Remove cover...

Page 43: ...ne or more Esc to switch to the standard display interface Press Prg display interface input password Press ENTER input repair level password 22 starting from the rightmost digit each input a digital confirm with ENTER If the password is correct it will display the first parameters can be modified network address Press UP DOWN to select parameters should be set up Press ENTER to move to the parame...

Page 44: ...arameters Valve body parameter setting 9 9 Nominal step motor speed 250Hz SHE 175valve cannot be changed Nominal current Stable current Control parameter settings 7 9 LowSH protection valve value 1K LowSH differential time 5s Control parameter settings 8 9 MOP protection valve value 50 C MOP integration time 10s Drive hardware configuration 3 9 Type of probe S1 4 20mA 0 30bar Unit type Tube shell ...

Page 45: ...parameters Refrigerant R134a Selected based on the refrigerant type of the unit Valve Danfoss ETS250 Sensor S1 4 20 mA 0 10 0 V Automatically brought out by subsequently set parameters Control mode shell and tube unit Overheat degree 6 Valve opening upon start 50 Pre positioning delay 6 Valve opening in standby state 0 Power supply mode 1 Available values include 1 0 24 V AC 2 1 24 V DC default va...

Page 46: ...in 80 PID integration time 40 PID derivation time 1 5 Minimum number of valve steps 350 Maximum number of valve steps 3810 Number of steps for valve closing 3970 Valve rate 250 LowSH protection threshold 1 LowSH protection integration time 2 5 LOP protection threshold 50 LOP protection integration time 4 MOP protection threshold 50 MOP protection integration time 10 Low overheat degree alarm delay...

Page 47: ...sically the operation is the same 1 Welcome page The first welcome page as the figure 6 1 Note use the user password 58806 or administrator password 40828 to enter the white window Use the administrator password 40828 to enter the purple window Welcome page Mode selection Status information Timer on off Time settin g Touch screen setting Alarm record history Alarm record history inquiry Condition ...

Page 48: ...is correct Green indicator is the touch screen operation indicator under normal condition it flashes with low frequency Red indicator is communication indicator under normal condition it flashes with high frequency if not please check if the communication wire connected with the main control board is connected properly and tightly Main page Figure 6 2 The main page displays the current status cont...

Page 49: ...ase inspect in the first page of status information if the minimum running time is satisfied The shutting down process will be continued when minimum running time is satisfied Pause The compressor startup conditions are not satisfied The compressor startup condition includes 1 Water temperature is not satisfy with compressor startup condition 2 Water temperature needs to be higher than compressor ...

Page 50: ...the timer Heating mode is only available for the heat pump unit Note under the local control mode remote control and timer control are invalid under the remote control mode local control and timer control are invalid under the timed control mode local control and remote control are invalid 2 Startup operation It needs to confirm below before startup Mode setting is correct Operation mode cooling h...

Page 51: ...information The compressor startup conditions include temperature of oil temperature sensor interval time of restart startup temperature of compressor and so on The startup can be confirmed right now but unit will start until the compressor startup conditions are met otherwise the main page will keep displaying that compressor start conditions are not met please check status information Please ref...

Page 52: ...mperature to be lower than water temperature of paused state The unit enters pause state and compressor stops operating Control water temperature to be higher than water temperature of compressor starting compressor starts and enters operating state Shutting down the unit enters shutting down state when carry out operation of shutdown to the unit After shutdown is finished unit enters standby stat...

Page 53: ...r displaying of unit with oil temperature sensor Figure 6 6 Displaying contents of status information including the following Display refrigerant type of the unit Display operating time of compressor and water pump Display times that compressor starts You can check which state the unit operates in 25 50 75 100 Display if unit has been set with a limit of maximum load ...

Page 54: ... Elapsed is ＹＥＳ Note when the compressor has oil temperature sensor it displays that the oil temperature is satisfied with compressor start When it has no oil temperature sensor it displays the remaining time of oil heating It depends on the unit It displays the refrigerant type on the top left of the screen To start the unit must meet the following conditions Delaying Restart need to be NO if it ...

Page 55: ...tion switch input state switches to ON and unit enters fault protection state Normal state of compressor overload protection switch is OFF and normal state of rest protections is ON Figure 6 8 Remark subject to the actual principle diagrams Remote start stop it displays the status of remote start or remote stop User needs to install the point contact type control switch Chilling Chilled water flow...

Page 56: ...unit is in a shutdown state all state display is OFF According to the startup shutdown command the relative switch action is activated Figure 6 9 Remark subject to the actual principle diagrams User parameter setting password interface Press Parameter setting in the main page then password input interface appears Input the password 40828 and enter the user parameter setting interface Password inpu...

Page 57: ... of parameter setting out of range is not accepted Press Enter button to confirm input Press CLR button to cancel input then the keyboard for number input disappears Noun explanation The temperature adjustment cycle it represents each execution cycle of the judgment of load or unload If it is set to be 60S that means every 60 seconds system judges the unit temperature and check if it needs to load...

Page 58: ...f maximum load 1 maximum load is up to 75 2 maximum load is up to 50 Timer setting of startup or shutdown Only when control mode is timer it will display 5 1 User parameter setting mode selection Press Clock and enter the clock setting page as figure 6 13 Click the setting numerical keyboard then the input numerical keyboard appears Input the clock and press ENT to save the setting CLR represents ...

Page 59: ...art or shutdown according to the timer setting If the unit needs to continue running for a period for example start from Tuesday 10 00 and shutdown at 16 00 Thursday user can set as 10 00 and switch the button from Invalid to Valid in the timer starting setting of Tuesday then set as 16 00 and switch the button from Invalid to Valid in the timer shutdown setting of Thursday rest timer buttons are ...

Page 60: ...iminated green represents fault has been eliminated Note the high pressure protection cannot resume automatically user needs to find the high pressure protection switch and reset it manually the over load protection cannot resume automatically user needs to find the thermal relay in the control cabinet and reset it manually 6 1 Alarm history Press the Detailed and enter record page it records the ...

Page 61: ...DX type water cooled screw chiller PCB Control MCAC CTSM 2014 03 60 Figure 6 17 Please refers to the actual operation interface it is subject to change without notice ...

Page 62: ...he module will cut off control circuit immediately The module with phase sequence control can prevent motor reversal due to the adverse consequences When any one phase loses the module will cut off main power after a short delay to protect the motor from burning When phase unbalance happens it cuts the power immediately In order to avoid interference and discriminate between false voltage drop and...

Page 63: ...red on the malfunction record page of touch screen Sometimes if the malfunction cannot be solved by reset consider replace the pressure switches Evaporator protection Low Chilled Leaving Water Temperature PCB is programmed to shut the chiller down if the leaving water temperature drops below 4 C When water temperature rises up to 10 the safety resets and the chiller restarts Besides the chillers a...

Page 64: ...0 380 Total input kW 0 3 0 3 0 3 0 3 0 3 0 3 0 6 0 6 0 6 0 6 Total Amps A 1 36 1 36 1 36 1 36 1 36 1 36 2 72 2 72 2 72 2 72 NOTE 1 Customer to specify the exact nominal power supply available at site so that electrical components are selected accurately 2 Main power must be supplied from a single field supplied and mounted fused circuit breaker 3 The compressor crankcase heaters must be energized ...

Page 65: ...hich is similar to the permissible overload feature of the motor it is used to provide overcurrent protection for the compressor and fan For compressor overload protection the major loop current of the motor is converted to an AC 0 5 A current signal by the current mutual inductor Then the thermal overload relay performs overload protection For fan overload protection the thermal overload relay is...

Page 66: ...he spring pushes the closed component to the valve seat once the electromagnetic force disappears and the valve is closed Voltage of the solenoid valve washer is AC220V and it is driven directly by the main control board output 3 Electrical Parts parameter setting 1 Power protector module setting in detailed Dial 1 switch to ON position Keep 2 switch to OFF position The default over voltage settin...

Page 67: ...s only when the system is powered off 3 Time Relay Time relay use omron H3Y type 4 Compressor and fan thermal overload relay Thermal overload relay takes advantage of heating effect to protect the compressor and fans T 6S Power LED On display red Time s up LED Up display green TEST key to press to test whether the overload relay is normal in stop condition Reset key to press to reset the overload ...

Page 68: ... set the value to 4 15 Unit Type Maximum Running Current of Compressor Transformation Ratio of Current Transformer Thermal Relay Value of Compressor 255 126 200 5 3 2 320 150 200 5 3 8 400 200 300 5 3 4 485 232 300 5 3 9 630 295 400 5 3 7 860 400 500 5 4 1 970 464 300 5 3 9 1060 497 300 400 39 3 4 1260 589 400 5 3 7 1490 695 500 5 and 400 5 3 7 4 1 6 Main base controller DIP setting Digital switch...

Page 69: ...iring 1 Wiring diagram Remote Start Remote Stop Alarm Running indicator Wiring Diagram of 255 320 400 485 630 860 ELECTRICAL CONTROL POWER SUPPLY Remote Start Remote Stop 1 Alarm 2 Alarm Wiring Diagram of 970 1060 1200 1260 1490 2 Recommended cable and mould case circuit breaker ...

Page 70: ...at is the capacity of breaker device should be increased properly Phase line PE line 255 25 16 160 320 35 16 160 400 50 25 250 485 70 35 250 630 95 50 400 860 150 70 400 970 185 95 630 1060 2 70 70 630 1260 2 95 95 630 1490 2 120 120 800 Note The length of leading in power cables in the unit cannot exceed 180 m 3 Cooling and chilled water pump wiring Chilled water pump wiring for 255 320 400 485 6...

Page 71: ...0 Chilled water pump wiring for 970 1060 1200 1260 1490 models Cooling water pump wiring for 255 320 400 485 630 860 models contactor Intermediate relay control cabinet wiring terminal Pump motor contactor Intermediate relay control cabinet wiring terminal Pump motor ...

Page 72: ...real time Once the cooling water stops flowing the water flow switch sends an alarm signal to the controller which will perform timely processing to prevent accidents from occurring Note A water flow switch is only a protection switch and cannot be used as a signal for unit power on or power off Cooling water pump wiring Diagram of 255 320 400 485 630 860 models Cooling water pump wiring Diagram o...

Page 73: ...witch water pump linked control alarm indication etc are reserved in the electrical cabinet of the unit with the numbers shown in the diagram below Remote start stop switch need to use inching switch Lamp input 220VAC Only double head Inside electric control cabinet Customer wiring terminal Inside electric control cabinet Remote Start Pump intermediate relay Refrigeration lamp 1 2 3 4 5 6 7 8 Remo...

Page 74: ...a specialized company to unload the machine Safety is only guaranteed if these instructions are carefully followed If this is not the case there is a risk of material deterioration and injuries to personnel 1 Unit installation 1 Lifting When transporting the unit please make sure there is no any collision happens between the unit and other objects Move the unit by placing a roller in the bottom of...

Page 75: ...nd the basement to ensure the drainage unblocked To eliminate the vibration and noise put an absorber between the unit and basement and keep the unit in balance Install a shockproof foundation when necessary Vibration isolators are recommended for all roof mounted installations or wherever vibration transmission is a consideration Neoprene Isolation is optional it is recommended for normal install...

Page 76: ... 1490 D mm 1600 1600 1600 1600 1800 1800 1800 1800 2000 2000 E mm 880 880 1000 1000 1220 1360 1440 1440 1540 1640 Fixation of unit Chart 1 Chart 2 Note 1 For chart 1 please reserve the installation holes for foundation bolt on the basement according to installation basement diagram 2 For chart 2 reserve the holes for the installation of absorber on the basement Model Load kg Load N Deflection mm V...

Page 77: ...t for wiring 4 The floor is solid enough and the location should not easily bring about resonance or noise 5 Put the unit indoors which should be well ventilated with low humidity and little dust Single compressor parataxis type unit 700 600 3100 600 Dual compressors parataxis type unit 2000 3500 600 600 700 2 Water Pipeline System installation 1 Water quality control When industrial water is used...

Page 78: ...start up the unit for a long time 4 The power supply was cut off and needn t change the water in system Ethylene and Propylene Glycol Factors A glycol solution is required when the unit with condition as mentioned The use of glycol will reduce the performance of the unit depending on concentration Ethylene Glycol Ethylene glycol Evaporator side Quality of glycol Cooling capacity modification Power...

Page 79: ...ecreased air density will reduce condenser capacity and reduce the unit s performance For performance at elevations other than sea level refer to below table Maximum allowable altitude is 1800 meters Evaporator temperature drop factors Performance tables are based on a 5o C temperature drop through the evaporator Adjustment factors for applications with temperature ranges from 3 to 6 in follow tab...

Page 80: ...o the variety of piping practices it is advisable to follow the recommendations of local authorities The installation and insulation of the water pipelines of the air conditioning system shall be designed and guided by design professionals and confirm to the corresponding provisions of the HVAC installation specifications Basically the piping should be designed with a minimum number of bends and c...

Page 81: ...n the unit Generally the refrigerant pipe side of the evaporator is the chilled water outlet side 3 The chilled water pipeline system must be provided with the soft connection thermometer pressure gauge water filter electronic scale remover check valve target flow controller discharge valve drain valve stop valve expansion tank etc 3 The water system must be fitted with the water pump with appropr...

Page 82: ...strainer should be placed for enough upstream to prevent cavitation at the pump inlet consult pump manufacturer for recommendations The use of a strainer will prolong pump life and help maintain high system performance levels 7 The flushing and insulation of the water pipelines shall be carried out before it is connected with the unit so as to prevent dirt from damaging the unit 8 The design water...

Page 83: ...ny water piping to the unit must be protected to prevent freezing There are reserved terminals for the auxiliary electrical heater Logic in PCB will transmit ON OFF signal by checking the leaving evaporator water temperature Note The unit only supplies the ON OFF signal but not the 220V power If a separate disconnect is used for the 220V supply to the cooler heating cable it should be clearly mark...

Page 84: ...supply cable is connected to the terminals of L1 L2 L3 N and PE and the terminals need to be fixed again after 24h running the minimum allowed time Please seal the entering wiring hole after users installed the main power wires in order to avoid the dust entering into electric control cabinet Caution it is suggested that to use appropriate tools to make sure that a enough height to install the mai...

Page 85: ...ater pump is started before starting the machine CAUTION An independent power supply box needs to be equipped with the power supply of the water pump 10 The wiring ports for remote start stop flow switch cool warm switch water pump linked control alarm indication etc are reserved in the electrical cabinet of the unit 11 Passive inching button is used for remote start and stop and the flow switch m...

Page 86: ...eness The screws might be loose due to the factors such as long distance transport and hoisting of the master compressor Or the electrical elements e g air switch AC contactor etc in the control cabinet of the master compressor and the compressor might be damaged 5 Carefully inspect all the electrical lines with a multi meter and whether the connections are properly installed Carry out measurement...

Page 87: ...ctly The compressor overload protection value generally equals to the set value of heat relay multiplied by variable ratio of current inductor which is 250 5 50 in the following case 11 Inspect whether the value of phase loss and reversal protection is set correctly The over under voltage protection value shall be 10 of the rated voltage 3 Refrigeration System Inspection 1 The discharge line valve...

Page 88: ... the liquid air sampling stop valve is open 5 After the unit is installed and before connected it is principle required to tighten the connections in the electrical cabinet of the unit one by one 6 Inspect the bolts of the unit for looseness After the unit is transported and installed it is required to inspect whether the fixing bolts of the unit e g fixing bolts at compressor base angle at post a...

Page 89: ...f air cooled heat pump unit for user s reference as for the details the operation manual supplied with the unit shall be final 9 Target type flow control is set on the chilled water pipeline which shall be installed at the chilled water outlet of the unit The NO contact of the target type flow control in the chilled water system shall be connected to the control circuit as per the wiring diagram N...

Page 90: ...a of R22 and R134a refrigerant is shown in table 1 In the pressure gauge scale taking the right figure for example the values outside of the black circle are pressure values unit bar and the values of the red blue and green circles indicate saturation temperatures of refrigerants R404A R22 and R134a respectively under the relative pressure The types of refrigerants indicated in different pressure ...

Page 91: ...erature points displayed on the display screen are within the normal range Before the operation of the unit the showed temperatures of discharge and fin and the ambient temperature are close to the current actual ambient temperature and whether the entering and leaving water temperatures are close to the water temperature at the user side If there is any obvious deviation of the above temperatures...

Page 92: ... 91 Keep good record of unit data during commissioning Working Condition Refrigeration Discharge temp 55 75 Suction temp 4 13 Suction super heating degree 4 10 Discharge super heating degree 20 35 Discharge pressure MPa 1 3 1 45MPa Suction pressure MPa 0 37 0 45MPa ...

Page 93: ...e remaining gas pressure and move the cylinders to a place designated for their recovery Do not incinerate 7 Ensure that you are using the correct refrigerant type before recharging the unit Charging any refrigerant other than the original charge type R 22 will impair machine operation and can even lead to a destruction of the compressors The compressors operating with this refrigerant type are lu...

Page 94: ...Remove condenser heads at least once a year to inspect the condenser tubes and clean if required Recommended maintenance schedule This chapter shows the preventive maintenance of Midea screw chiller Correct maintenance and timely service will make the chiller in the best condition and with best performance beside it can prolong the lifespan of chiller The customer has responsibility to appoint qua...

Page 95: ...ecline obviously Inspect the oil quality monthly to see if there s dirt or deterioration otherwise replace the oil and filter core if necessary by specialized technicians Make chemical analysis of the lubricating oil if emulsification phenomenon occurs change the oil of same brand Heat exchangers Adjust the water flow to keep the high low pressure within normal range high pressure 0 6 1 2MPa low p...

Page 96: ...for installation and the after sale personnel or professionals in the factory will determine whether change is necessary 3 Short connection is forbidden when all protection functions of the unit are normal Ensure all protection functions are available and reliable Various protection switches in the unit are for safety of the unit or user and are not permitted to be short connected in principle If ...

Page 97: ...sonnel or professionals in the factory 7 If any exceptional case occurs to the unit it is forbidden to forcibly start up the unit unless under the instructions of professionals Exceptional temperature pressure sound or vibration etc of the unit during the running shall be clearly recorded in details and reported to after sale personnel or professionals in the factory It is forbidden to forcibly st...

Page 98: ... will indicate whether water treatment is adequate in the water circuit Too much scale will cause big loss of capacity and efficiency Refer to the following pressure temperature curve for condition in heat exchangers High pressure cooling water temperature high pressure beyond 0 6 1 2MPa is abnormal Fig 26 High pressure at full load standard unit Low pressure chilled water temperature low pressure...

Page 99: ... generates hard scale 4 Water with much Cl Dirt Ultra strong Corrosive to copper and iron 5 Water with much SO4 2 and SiO2 2 Hard Strong Generates hard CaSO4 and CaSiO2 6 Water with much Fe3 Large quantity hard Strong Generates deposits Fe OH 3 and Fe2O3 7 Odorous water Large quantity Ultra strong Generates sulfide ammonia and marsh gas especially H2S which has great corrosion to copper 8 Water wi...

Page 100: ...h the cooling water circuit Make sure tower blow down or bleed off is operating It should be recognized that atmospheric air contains many contaminants that increase the need for proper water treatment The use of untreated water can result in corrosion erosion sliming scaling or algae formation Midea assumes no responsibility for the results of untreated or improperly treated water Refrigerant Cir...

Page 101: ...tor for a visual inspection f The condenser refrigerant level to be included between the condensing and the sub cooling sections by checking the sight glass installed on each condenser for a visual inspection 5 Verify the sight glass on the liquid piping to be fully charged If one of the above parameters exceeds the limits unit may require an additional refrigerant charge Note Refrigerant removing...

Page 102: ...r the replacement extract vacuum in the gas part g After the vacuum extraction keep the negative voltage until the resumed vacuum in the unit meets the requirements h Open the angle valve of liquid system and compressor liquid air stop valve to ensure the loop of the entire system is unobstructed i Add proper amount of refrigerant generally 5 10k Oil Charging Low Oil Recharging Pre cautions in cha...

Page 103: ...ean internal and external filters To determine the oil pressure drop due to the oil lines and external filter only connect a gage to the oil pressure bleed port Compare this value to the discharge pressure read at the touch screen If this value exceeds 150 kPa replace the external filter Moisture Liquid Indicator Clear flow of liquid refrigerant indicates sufficient charge in the system Note howev...

Page 104: ... pump motor from burn because there is lack of cooling water or chilled water Protection of sensor fault Ensures the data from sensor is correct to prevent the system from wrong action Oil level and oil pressure difference protection Ensures the compressor to run normally High discharge temperature protection Makes the compressor run safely under permitted conditions Phase reversal phase loss phas...

Page 105: ...display leaving cooling water temperature fault and chiller stops according to abnormal shutdown program After the sensor reset fault on screen must be cleared manually when both temperature and time condition gets satisfied the chiller can restart Discharge temperature sensor short circuit open circuit display discharge temperature fault and chiller stops according to abnormal shutdown program Af...

Page 106: ...ction module trips Perform abnormal protective shutdown program immediately Fault on screen must be confirmed and cleared manually when both temperature and time condition gets satisfied the chiller can restart Compressor overload protection Thermal overload relay trips when heat storage reaches trip point Faulted compressor will stop immediately to abnormal protective shutdown program and other n...

Page 107: ...mal when Y type switch to type 2 The vibration during operation cause the contact to loosen 5 Anti freeze Protection Anti freeze switch OFF The compressor stop running immediately Reset manually on the touch screen 1 The chilled water flow fall sharply the water temperature too low 2 Anti freeze switch is damaged or wiring connection is abnormal 6 Water Flow Fault The water flow switch continue di...

Page 108: ...the touch screen 1 Too low oil temperature when starting lead to too low pressure difference and return oil is abnormal 2 Return oil solenoid valve failure or plugging in the filter 3 Mix different oil types and return oil system is abnormal 4 Oil level switch failure or wrong wiring connection 5 The oil volume not enough 10 High Discharge Temperature Protection The compressor discharge temperatur...

Page 109: ...275 9 32 40 57 72 8 94 112 2 63 7 261 4 33 38 89 73 8 643 113 2 559 6 247 8 34 37 3 74 8 358 114 2 489 5 234 9 35 35 78 75 8 084 115 2 422 4 222 8 36 34 32 76 7 82 116 2 357 3 211 4 37 32 94 77 7 566 117 2 294 2 200 7 38 31 62 78 7 321 118 2 233 1 190 5 39 30 36 79 7 086 119 2 174 0 180 9 40 29 15 80 6 859 120 2 117 1 171 9 41 28 81 6 641 121 2 061 2 163 3 42 26 9 82 6 43 122 2 007 3 155 2 43 25 8...

Page 110: ...9 1 718 109 0 478 10 58 270 30 8 013 70 1 659 110 0 464 9 55 099 31 7 669 71 1 601 8 52 123 32 7 342 72 1 546 7 49 328 33 7 031 73 1 492 6 46 703 34 6 735 74 1 441 5 44 235 35 6 453 75 1 392 4 41 896 36 6 183 76 1 346 3 39 697 37 5 927 77 1 301 2 37 628 38 5 683 78 1 258 1 35 682 39 5 450 79 1 217 0 33 849 40 5 228 80 1 177 1 32 115 41 5 016 81 1 139 2 30 483 42 4 813 82 1 101 3 28 944 43 4 620 83...

Page 111: ... 8 62 69 2 29 109 0 77 10 42 25 30 8 31 70 2 22 110 0 75 9 40 56 31 8 01 71 2 16 8 38 76 32 7 72 72 2 10 7 37 05 33 7 45 73 2 04 6 35 43 34 7 19 74 1 98 5 33 89 35 6 94 75 1 92 4 32 43 36 6 69 76 1 87 3 31 04 37 6 46 77 1 81 2 29 72 38 6 24 78 1 76 1 28 47 39 6 03 79 1 71 0 27 28 40 5 82 80 1 66 1 67 74 41 5 63 81 1 62 2 26 13 42 5 43 82 1 57 3 25 03 43 5 25 83 1 53 4 23 99 44 5 08 84 1 49 5 22 99...

Page 112: ...Temp Ratio Temp Ratio Temp Ratio Temp Ratio 40 1630 77 35 1178 11 30 860 97 25 636 08 20 474 78 15 357 83 10 272 18 5 208 83 0 161 56 5 125 97 10 98 96 15 78 29 20 62 37 25 50 00 30 40 34 35 32 73 40 26 71 45 21 92 50 18 08 55 14 99 60 12 48 65 10 44 70 8 78 75 7 41 80 6 28 85 5 34 90 4 56 95 3 91 100 3 37 105 2 91 110 2 52 115 2 19 120 1 91 125 1 67 130 1 46 135 1 28 140 1 13 145 1 00 150 0 89 ...

Page 113: ...Conditioner Division Midea Group Address Midea Headquarters Building 6 Midea Avenue Beijiao Shunde Foshan Guangdong China Postal code 528311 Tel 86 757 26338346 Fax 86 757 22390205 cac midea com global midea com Note The data in this book may be changed without notice for further improvement on quality and performance ...

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