Danfoss ADAP-KOOL AK-PC 783 Скачать руководство пользователя страница 29

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AK-PC 783

Capacity

controller RS8GN202 © Danfoss 11-2013

Power supply module AK-PS 075 / 150 / 250

Function

24 V supply for controller.

Supply voltage

230 V a.c or 115 V a.c. (from 100 V a.c. to 240 V a.c.)

Placing

On DIN-rail

Effect

Type

Output tension

Output current

Power

AK-PS 075

24 V d.c.

0.75 A

18 VA

AK-PS 150

24 V d.c. (adjustable)

1.5 A

36 VA

AK-PS 250

24 V d.c. (adjustable)

2.5 A

60 VA

Dimension

Type

High

Width

AK-PS 075

90 mm

36 mm

AK-PS 150

90 mm

54 mm

AK-PS 250

90 mm

72 mm

Connections

AK-PS 075

AK-PS 150

AK-PS 250

Supply to a controller

Содержание ADAP-KOOL AK-PC 783

Страница 1: ...Capacity controller with cascade control AK PC 783 Design Guide ADAP KOOL Refrigeration control systems...

Страница 2: ...oup MT 58 Set control of suction group LT 61 Set control of cascade heat exchanger 64 Set oil management 65 Setup control of condenser fans 67 Setup control of pump function 69 Setup control of heat 6...

Страница 3: ...crew compressors Digital scroll compressor Oil equalisation function on MT circuit Oil management Either shared or individual for all of the com pressor s oil valves in the LT circuit Receiver pressur...

Страница 4: ...stems requirements are changed Flexible concept Controller series with common construction One principle many regulation uses modules are selected for the actual connection requirements The same modul...

Страница 5: ...w settings A corresponding application with many connections will give a setup with many settings From the overview display there is access to further displays for the compressor regulation and the co...

Страница 6: ...ormation display on the screen A corresponding display exists for all earlier alarms Here you can upload information if you need further details about the alarm history Trouble shooting The controller...

Страница 7: ...with a specific software and by which input and output signals the relevant application will require If it is an application with few connections the controller module top part with belonging bottom...

Страница 8: ...data communication is connected to other controllers in a big ger network Connection types There are various types of inputs and outputs One type may for example receive signals from sensors and switc...

Страница 9: ...V d c AK PS 075 18 VA Supply for controller AK PS 150 36 VA AK PS 250 60 VA Accessories External display that can be connected to the controller module For showing say the suction pressure EKA 163B Di...

Страница 10: ...be connected to the same output group Solid state outputs Can be used for loads that are cut in and out frequently e g Oil valves fans and AKV valves Max 240 V a c Min 48 V a c Max 0 5 A Leak 1 mA Ma...

Страница 11: ...2 Danfoss 11 2013 11 Dimensions The module dimension is 72 mm Modules in the 100 series consist of one module Modules in the 200 series consist of two modules Controllers consist of three modules The...

Страница 12: ...roller is connected to a gateway type AKA 245 the controller s address must be set between 1 and 119 If it is a system manager AK SM then 1 999 Service PIN When the controller is connected to the data...

Страница 13: ...1 1 2 2 AI 2 3 4 3 AI 3 5 6 4 AI 4 7 8 5 AI 5 9 10 6 AI 6 11 12 7 AI 7 13 14 8 AI 8 19 20 9 AI 9 21 22 10 AI 10 23 24 11 AI 11 25 26 12 DO 1 31 32 13 DO 2 33 34 14 DO 3 35 36 15 DO 4 37 38 16 DO 5 39...

Страница 14: ...signals Supply voltage The supply voltage to the module comes from the previous mod ule in the row Supply voltage to a pressure transmitter can be taken from either the 5 V output or the 12 V output d...

Страница 15: ...S 32 P0LT P0MT PcLT PcMT Paux AKS 32R AKS 2050 1 xx bar AKS 32 1 zz bar U 0 5 V 0 10 V On Off Ext Main switch Day Night Door Level switch Active at Closed Open Point 5 6 7 8 Type AI5 AI6 AI7 AI8 Point...

Страница 16: ...Function The module contains 8 inputs for on off voltage signals Signal AK XM 102A is for low voltage signals AK XM 102B is for high voltage signals Supply voltage The supply voltage to the module com...

Страница 17: ...3 4 3 DI 3 5 6 4 DI 4 7 8 5 DI 5 9 10 6 DI 6 11 12 7 DI 7 13 14 8 DI 8 15 16 Point Signal Active at DI Ext Main switch Day Night Comp safety 1 Comp safety 2 Level switch Closed voltage on Open voltage...

Страница 18: ...le comes from the previous module in the row Supply voltage to a pressure transmitter can be taken from either the 5 V output or the 12 V output depending on transmitter type Galvanic isolation The in...

Страница 19: ...LT P0MT PcLT PcMT Paux AKS 32R AKS 2050 1 xx bar AKS 32 1 zz bar U 0 5 V 0 10 V On Off Ext Main switch Day Night Door Level switch Active at Closed Open AO 0 10 V Terminal 9 12 V Terminal 10 5 V Termi...

Страница 20: ...Light emitting diodes There are two rows with LED s They mean Left row Voltage supply to the controller Communication active with the bottom PC board red error Status of outputs DO1 to DO8 Right row...

Страница 21: ...Module Point Terminal Active at 1 DO 1 25 27 2 DO 2 28 30 3 DO 3 31 33 4 DO 4 34 36 5 DO 5 37 39 6 DO 6 40 41 42 7 DO 7 43 44 45 8 DO 8 46 47 48 Signal Active at DO Comp 1 Comp 2 Fan 1 Alarm Solenoid...

Страница 22: ...ion Auto the controller carries out the control Light emitting diodes There are two rows with LED s They mean Left row Voltage supply to the controller Communication active with the bottom PC board re...

Страница 23: ...Pt 1000 ohm 0 C S2 Saux Ss Sd Shr Stw Scasc Pt 1000 P AKS 32R AKS 32 P0MT P0LT PcMT PcLT Paux Prec AKS 32R AKS 2050 1 xx bar AKS 32 1 zz bar U 0 5 V 0 10 V On Off Ext Main switch Day Night Door Level...

Страница 24: ...valves must be from a separate supply which must be galvanically separated from the supply for the control range Power requirements 7 8 VA for controller 1 3 VA per valve A UPS may be necessary if the...

Страница 25: ...0 ETS White Black Red Green CCM CCMT KVS 15 White Black Green Red KVS 42 54 CCM Point 1 2 3 4 5 6 7 8 Type AI1 AI2 AI3 AI4 AI5 AI6 AI7 AI8 Terminal 17 12 V Terminal 18 5 V Terminal 19 20 Cable screen...

Страница 26: ...e module contains two analog voltage outputs of 0 10 V Supply voltage The supply voltage to the module comes from the controller module Placing The module is placed on the PC board in the controller m...

Страница 27: ...es for day night change over Fixed defrost times Saving of alarm log in case of power failure Saving of temperature log in case of power failure Connection The module is provided with plug connection...

Страница 28: ...nected to either display output A B C and D Ex A P0 Suction pressure in C B Pc Condensing pressure in C When the controller starts up the display will show the output that is connected 1 output A 2 ou...

Страница 29: ...from 100 V a c to 240 V a c Placing On DIN rail Effect Type Output tension Output current Power AK PS 075 24 V d c 0 75 A 18 VA AK PS 150 24 V d c adjustable 1 5 A 36 VA AK PS 250 24 V d c adjustable...

Страница 30: ...on module The 24 V can be sourced from the same supply that supplies the controller The supply for the communication module is galvani cally separated from the connected extension modules The terminal...

Страница 31: ...AK PC 783 Capacity controller RS8GN202 Danfoss 11 2013 31...

Страница 32: ...up in a network with a gateway a system manager or a clock module can be mounted in the controller Start stop of regulation Regulation can be started and stopped via the software External start stop...

Страница 33: ...upply voltage is supplied from the module s terminal board where there is both a 5 V supply and a 12 V supply When programming the pressure trans mitter s pressure range must be set ON OFF voltage inp...

Страница 34: ...on MT x Regulation of a cascade heat exchanger x Regulation of compressor capacity Control sensor P0 x PI regulation x Max number of compressors 4 MT 4 LT 5 MT 3 LT Max number of unloaders each compre...

Страница 35: ...circuit If signals are to be received from one or more parts of a safety circuit each signal must be connected to an ON OFF input Day night signal for raising the suction pressure The clock function c...

Страница 36: ...mpressor lack of oil Condenser Fans with EC motors speed controlled Pc MT regulates flooating based on temperature sensor Sc3 Cascade exchanger Control sensor Scasc3 Valves Stepper valve ETS and Solen...

Страница 37: ...setback of suction pressure Separate alarm functions via DI Load shedding Start of Heat recovery Liquid level Oil level Pulse reset of oil management 6 On off outputs Compressors motors 6 Unloaders Fa...

Страница 38: ...nection to the connected modules This status can be followed by the light emitting diode When the two catches for the DIN rail mounting are in open posi tion the module can be pushed into place on the...

Страница 39: ...ure Sc3 3 AI 3 5 6 Pt 1000 Discharge temperature Sd LT 4 AI 4 7 8 Pt 1000 Suction gas temperature Ss MT 5 AI 5 9 10 Pt 1000 Suction pressure P0 MT 6 AI 6 11 12 AKS 32R 12 Condensing pressure Pc MT 7 A...

Страница 40: ...heat exchanger Scasc2 5 1 AI 1 1 2 Pt 1000 Temp heat exchanger Scasc3 2 AI 2 3 4 Pt 1000 3 AI 3 5 6 Oil receiver Prec Oil 4 AI 4 7 8 AKS 2050 59 Speed control compressor MT 5 AO 1 9 10 0 10 V Speed co...

Страница 41: ...AK PC 783 Capacity controller RS8GN202 Danfoss 11 2013 41 Example continued...

Страница 42: ...ated from the supply The and 24V input must not be earthed If using stepper motor valves the supply for these must be pro vided from a separate power supply For CO2 facilities it will also be necessar...

Страница 43: ...wer supply module 230 V 115 V to 24 V d c AK PS 075 18 VA Supply for controller 080Z0053 AK PS 150 36 VA 080Z0054 x AK PS 250 60 VA 080Z0055 Accessories External display that can be connected to the c...

Страница 44: ...44 Capacity controller RS8GN202 Danfoss 11 2013 AK PC 783...

Страница 45: ...roller Is fitted Is connected We have decided to work on the basis of the example we went through previously i e the following modules AK PC 783 controller module AK XM 204A output module AK XM 208C a...

Страница 46: ...te on the left hand side of the light emitting diodes and the plate on the right hand side for the red address changers Lift the top part off the basic module 2 Mount the extension module in the basic...

Страница 47: ...The basic module must not be connected to voltage Mounting and wiring continued When the two snap catches for the DIN rail mounting are in the open position the module can be pushed into place on the...

Страница 48: ...inputs a galvanically insulated module should be inserted Signal Module Point Terminal Signal type Active at Compressor 1 MT 2 1 DO 1 25 26 27 ON Compressor 2 MT 2 DO 2 28 29 30 ON Compressor 3 MT 3...

Страница 49: ...nting and wiring continued The screen on the pressure transmitter cables must only be connected at the end of the controller The supply voltage for the pressure transmitter should be taken from the sa...

Страница 50: ...ady in just under one minute when the light emitting diode Status starts flashing slowly 5 When there is a network Set the address and activate the Service Pin 6 The controller is now ready to be conf...

Страница 51: ...eration This section describes how the controller Is configured Is operated We have decided to work on the basis of the example we went through previously i e compressor control with 4 MT compres sors...

Страница 52: ...n overview of it will always appear In this case the overview is empty This is because the controller has not yet been set up The red alarm bell at the bottom right tells you that there is an active a...

Страница 53: ...oss of filling Compressor Group MT circuit and LT circuit Refrigerant MT 134a LT CO2 R744 4 and 2 compressors with cyclic operation First compressor is speed controlled Safety monitoring of each compr...

Страница 54: ...for the specific system and a corresponding access code for this person The controller will utilize the same language that is selected in the service tool but only if the controller contains this lang...

Страница 55: ...2 Select Lock Unlock configuration 3 Select Configuration lock Press the blue field with the text Locked 4 Select Unlocked Select Unlocked Configuration continued The controller can only be configured...

Страница 56: ...e value of the required setting In the first field you enter a name for what the controller will be controlling The text written in this field can be viewed at the top of all screens together with the...

Страница 57: ...roller is to make coordination between MT and LT control management Oil management Oil control enabled To be adjusted later on HP control High pressure control enabled To be adjusted later on Receiver...

Страница 58: ...number of compressors No of unloaders Set number of unloader valves Ext compressor stop An external switch can be connected which will start and stop the compressor control Variable compessor type Cho...

Страница 59: ...time at decreasing capacity 5 Compressors In this screen the capacity distribution between the com pressors is defined Capacities that need to be set depend upon the compressor application and Step c...

Страница 60: ...on safety Choose whether an overall common safety input for all compressors is desired If the alarm is activated all compres sors will be cutout Oil pressure etc Define here whether this type of prote...

Страница 61: ...for an MT group However it is not possible to choose screw compressors Please refer to the previous pages 1 Go to Configuration menu 2 Select Suction group 3 Set values for the reference Press the bu...

Страница 62: ...lues for capacity of the compressors Press the button to go on to the next page 6 Set values for main step and any unloaders Press the button to go on to the next page 7 Set values for safe operation...

Страница 63: ...nitoring of compressor Press the button to go on to the next page 9 Set operation time for compres sor Press the button to go on to the next page 10 Set times for safety cutouts Press the button to go...

Страница 64: ...ssibly two in parallel AKV is not recommended near the plate heat exchangers EVR in liquid line If a signal is required for a magnet valve in the liquid line Injection stat signal No signal Signal fro...

Страница 65: ...ack of oil is registered when the compressor is force controlled Forced controlled to ON with the setting Manual or with the changeover on an extension module Danfoss recommends this function to avoid...

Страница 66: ...or stop Oil cycle pre delay Delay time before oil pulses commence Oil cycle post delay Delay time for signal that will stop oil pulses High oil alarm delay If an activation of the level switch is not...

Страница 67: ...ode Select control mode for condenser Step Fans are step connected via relay outputs Step speed The fan capacity is controlled via a combination of speed control and step coupling Speed The fan capaci...

Страница 68: ...ires the use of a Sc3 outer temperature sen sor which must be fitted by the condenser s air inlet If yes the following settings will become visible FDD setting Set error detection function Tuning Will...

Страница 69: ...have not used this function in our example It is included for guidance only This function will only display in the configuration menu if it is enabled in the Select plant type menu Setup control of pu...

Страница 70: ...ys are not used The setting is included here for information 3 Display setup Display The following can be read for the four outputs Comp control sensor P0 in temperature MT and LT P0 i bar absolute MT...

Страница 71: ...lect General purpose 3 Define number of required functions We have not used the general purpose functions in our example The images are included for guidance only 3 The following number of different f...

Страница 72: ...ion For each thermostat adjust Name Which of the sensors is used Actual temp Temperature measurement on the sensor that is attached to the thermostat Actual state Actual status on the thermostat outle...

Страница 73: ...rm inputs 3 Voltage inputs The general volt inlet can be used to monitor external volt age signals Each volt inlet has a separate outlet to control external automatic controls Set the number of genera...

Страница 74: ...own in the display Reading the total reference Output Here you select the outlet function PWM pulse width modulated fx AKV valve Stepper signal for a step per motor or voltage signal Ref calc A Consta...

Страница 75: ...arlier Digital outputs Digital inputs Analog outputs Analog inputs We set up the controller s digital input functions by keying in which module and point on this module each one of these has been conn...

Страница 76: ...isch temp Pc Cond Pres S7 Warm brine Sc3 air on Ext Ref Signal 0 5 V 0 10 V Olie receiver Prec Stw2 3 4 8 Shr2 3 4 8 HC 1 5 Heat recovery Saux 1 4 Paux 1 3 Voltage input 1 5 0 5 V 0 10 V 1 5 V 2 10 V...

Страница 77: ...alarms that are current They will be shown with text in the three pictures All alarms that can occur can be set for a given order of priority High is the most important one Log only has lowest priori...

Страница 78: ...GN202 Danfoss 11 2013 AK PC 783 Press the button to go on to the next page 5 Set alarm priorities for thermostat and extra digital signals Configuration continued In our example we select the settings...

Страница 79: ...e a comparison of selected func tions and define inputs and outputs The result can be seen in the next section where the setup is controlled Configuration continued Press in the field against Configur...

Страница 80: ...umber and point number that does not exist The selected point number on the selected mod ule had been set up for something different The error is corrected by setting up the output correctly Remember...

Страница 81: ...utputs Press the button to go on to the next page 6 Check configuration of Analog Inputs Configuration continued The setup of the analog outputs appears as it is supposed to according to the wiring ma...

Страница 82: ...OFF MAN ON The output is forced to pos ON Before the control is started we check that all inputs and outputs have been connected as expected This controls requires that the setup is locked By means of...

Страница 83: ...xample of the connection between a defined output signal and a manual set value Check that all sensors show sensible values In our case we have no values This may be due to the following The sensor ha...

Страница 84: ...e pages the ones that can only be seen via the Scroll bar 4 Safety limits 5 Go back to the overview 6 Select condenser group Before the control starts we check that all the settings are as they should...

Страница 85: ...an only be seen via the Scroll bar 8 Safety limits 9 Go back to the overview and Move on to the ther mostat group Check the settings 10 Go back to the overview and Move on to the press sostat group Ch...

Страница 86: ...suction pressure to the current need during both day and night Shown on the left is an example of a schedule in which the suction pres sure is increased during night time operation In other cases whe...

Страница 87: ...t 3 The arrow of the two other address switches must point at 0 2 Push the Service Pin Press down the service pin and keep it down until the Service Pin LED lights up 3 Wait for answer from the system...

Страница 88: ...ist Press the red cross to remove cancelled alarms from the alarm list 5 Check active alarm again In our case we have a series of alarms We will tidy them up so that we only have those that are releva...

Страница 89: ...bottom of the display 2 Start control First start of control continued Press in the field against Main switch Select ON The controller will now start controlling the compressors and the fans Note Cont...

Страница 90: ...acity in percent Press in the blue field against Manual capacity If you need to manually adjust the capacity of the compressors you can use the following procedure WARNING If you force control the com...

Страница 91: ...AK PC 783 Capacity controller RS8GN202 Danfoss 11 2013 91 5 Regulating functions This section describes how the different functions work...

Страница 92: ...e and will ensure disconnection of compressor capacity frost protection Handling of sensor error Cap Ctrl Sensor P0 When P0 is used as the regulating sensor an error in the signal will mean that regul...

Страница 93: ...optimisation is performed Here the override function will itself adapt the suction pressure to the max permissible If a short change in the suction pressure is needed for example up to 15 minutes in c...

Страница 94: ...nstantly changing The Integrator is looking at the deviation between the set point and the current pressure only and increases reduces the requested capacity correspondingly The amplification factor K...

Страница 95: ...dynamic zone extension is reduced to 0 Via the Minimize number of couplings setting it is possible to influence how big the amplitude of the dynamic zone extension should be in order to minimize the c...

Страница 96: ...ing hour equalizing is carried out between compressors of the same type with the same total capacity At the different startups the compressor with the lowest number of operating hours will be started...

Страница 97: ...unload valves are combined with one step compres sors all compressors should be the same size 3 Speed regulated compressors can have different sizes in relation to subsequent compressors 4 When two s...

Страница 98: ...is now up to the frequency converter to bring the speed up to Start speed The capacity step will now be cut in and the required capacity determined by the controller The start speed always ought to be...

Страница 99: ...ollowing compressor steps If the variable part of the speed controlled compressor is smaller than the following compressors there will be holes in the capacity curve Example 1 speed controlled compres...

Страница 100: ...capacity has reached a value that allows the cut in of the next speed regulated compressor at start speed Afterwards both compressors will be cut in together and will run in parallel The following one...

Страница 101: ...will be started first then the first will be cut out and the second compressor will cut in Finally both compressors will be cut in together and will run in parallel The following one step compressors...

Страница 102: ...lay and safety functions Extra cascade The controller can send an injection signal to an external cascade control The signal will follow the injection signal Control sensors The following are used as...

Страница 103: ...suction pressure is again under the normal reference value The load shedding can then be activated again Alarm When a load shedding digital inlet is activated an alarm will be activated to inform tha...

Страница 104: ...Direct using an electrically operated expansion valve of the type AKV Four values are adjusted a start value for the Sd temperature min and max values for overheating and a period time for the AKV va...

Страница 105: ...and the reconnect value at 120 C Monitoring of min suction pressure P0 The function promptly cuts out all compressor steps if the suction pressure becomes lower than the permitted value The cutout lim...

Страница 106: ...principle for compressor A compressor that is shut down does not receive any oil When the compressor is in operation a signal from the compres sors oil level switch is expected When the signal is giv...

Страница 107: ...counters are reset Control principle for emptying the oil separator in the receiver The system can be controlled by a signal from a high level switch or a low level switch or it can be controlled by a...

Страница 108: ...hangeover between the pumps is permitted Start before stop 5 Automatic changeover between the pumps is permitted Stop before start This function is used when both pumps are controlled in shifts by the...

Страница 109: ...umed to have been repaired At the same time the alarm situation is reset the alarm is acknowl edged If the faulty pump has not been repaired this will still trigger an alarm and still result in change...

Страница 110: ...errors Cap Ctrl Sensor Pc If Pc is used as the control sensor an error in the signal will result in condensator capacity being controlled as a function of the connected compressor capacity The compre...

Страница 111: ...ure sensor becomes lower than the set cut in limit the heat recovery function is activated and the reference for the condenser temperature will be raised to a set value and simultaneously the chosen r...

Страница 112: ...capacity requirement becomes lower than the set minimum speed Start Min Speed regulation step regulation The controller starts the frequency converter and the first fan when the capacity requirement...

Страница 113: ...normal operation conditions Capacity limitation during night operation The function is used to reduce the noise from the fans to a minimum It is primarily used in conjunction with a speed control but...

Страница 114: ...e based on the actual pressure Alarm limits can be set for low and high pressure respectively including separate alarm delays The individual pressure control function can be adapted to the relevant ap...

Страница 115: ...g might be Check max and min settings Increase the integration time so that it is not mixed up with the balancing Reduce Kp to start with Start the process Adjust Kp until the process starts fluctuati...

Страница 116: ...onnection signal Unexpected disconnection of the compressor condensation fan or frequency convertor can result in unexpected temperature increases in the system If necessary use the necessary safety s...

Страница 117: ...uently read the historical values in the form of graph presentations The log only works when the clock has been set Forced operation via network The controller contains settings that can be operated f...

Страница 118: ...on locked P62 Manual setting of suction capacity in LT circuit P63 Setting of Control mode cond in LT circuit r23 Setting of Set Point for P0 in MT circuit r24 Readout of the total P0 reference in MT...

Страница 119: ...lve drive rate in steps per second This value is limited to 20 500 steps sec Holding Current The percent of the programmed Max Phase Current that should be applied to each phase of the stepper output...

Страница 120: ...via few compressors Preconditions for using this compressor application are All compressors are the same size The capacity regulated compressor can have up to three unload valves The main step and the...

Страница 121: ...to fill capacity gaps Operating hours are equalised between the one step compres sors 3 and 4 Compressor application 4 Only capacity controlled compres sors The controller is capable of controlling c...

Страница 122: ...capacity Decreasing capacity The small one step compressor is cut out when the speed regu lated compressor has reached minimum speed 30 Hz When the speed regulated compressor again reaches minimum sp...

Страница 123: ...f coupling pattern The same frequency band for both speed regulated compressors One step compressors of the same or different sizes depending on the choice of coupling pattern This compressor combinat...

Страница 124: ...xample 2 In this example the speed regulated compressors are of different sizes and the following one step compressors are also of different sizes Increasing capacity The smallest speed regulated comp...

Страница 125: ...AK PC 783 Capacity controller RS8GN202 Danfoss 11 2013 125...

Страница 126: ...__ Comp 12 safety Medium Comp X oil pressure cut out Compressor no x has been cut out on oil pressure safety Comp x over current cut out Compressor no x has been cut out on over current safety Comp 1...

Страница 127: ...r alarms stopped System alarms The alarm priority can not be altered on system alarms Control mode Low Manual comp cap Control Compressors capacity control runs i manual mode Control mode Low Manual c...

Страница 128: ...installation or site conditions can give rise to malfunctions of the control system and ultimately lead to a plant breakdown Every possible safeguard is incorporated into our products to prevent this...

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Содержание ADAP-KOOL AK-PC 783

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