background image

32 

Capacity 

controller RS8HF102 © Danfoss 2017-07 

AK-PC 772A

2

AK-PC 

772A

Application

Regulation of a compressor group MT

x

Regulation of a condenser group LT

x

Regulation of a parallel compression IT

x

Regulation of a gas cooler

x

Regulation of CO2 receiver pressure

x

Regulation of compressor capacity

Regulation sensor = P0

x

PI-regulation 

x

Max. number of compressor steps on MT + IT

3

Max. number of compressor steps on LT

2

Max. number of unloaders each compressor

3

Identical compressor capacities

x

Different compressor capacities

x

Speed regulation of 1 or 2 compressors

x

Run time equalisation

x

Min. restart time

x

Min. On-time

x

Liquid injection in suction line

x

External start/stop of compressors

x

Oil management

Oil equalisation

x

Suction pressure reference

Override via P0 optimization

x

Override via “night setback”

x

Override  via "0 -10 V signal"

x

Regulation of gas cooler

Regulation sensor = Sgc

x

Step regulation

x

Max. number of steps

4

Speed regulation

x

Step and speed regulation

x

Speed regulation first step

x

Limitation of speed during night operation

x

Heat recovery function for domestic water or room

x

Gas cooler pressure reference

Floating pressure reference

x

Setting of references for heat recovery functions

x

Design of a compressor and condenser control

Procedure:

1. Make a sketch of the system in question
2. Check that the controller’s functions cover the required 

application

3. Consider the connections to be made
4. Use the planning table. / Note down the number of connections 

./ add up

5. Are there enough connections on the controller module? – If 

not, can they be obtained by changing an ON/OFF input signal 
from voltage signal to contact signal, or will an extension 
module be required?

6. Decide which extension modules are to be used
7. Check that the limitations are observed
8. Calculate the total length of modules
9. The modules are linked together
10. The connection sites are established
11. Draw a connection diagram or a key diagram
12. Size of supply voltage/transformer

1

Sketch

Follow these 12 

steps

Make a sketch of the system in question.

Compressor and condenser functions

Summary of Contents for AK-PC 772A

Page 1: ...Capacity controller for small CO2 refrigeration system AK PC 772A User Guide ADAP KOOL Refrigeration control systems ...

Page 2: ...ontrol of MT compressors 56 Set control of LT compressors 60 Setup control of condenser fans 61 Setup control of high pressure 63 Setup control of receiver pressure 64 Setup control of heat recovery 65 Setup Display 66 Setup Functions for General purpose 67 Separate thermostat 68 Separate pressostat 68 Separate voltage signal 69 Separate alarm inputs 69 Separate PI function 70 Configuration of inp...

Page 3: ...arallel compressor Capacity control of up to 2 compressors on low pressure Up to 3 unloaders for each compressor Speed control of one or two compressors Up to 6 safety inputs for each compressor Option for capacity limitation to minimize consumption peaks When the compressor does not start signals can be transmitted to other controllers so that the electronic expansion valves will be closed Contro...

Page 4: ...systems 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 modules are used from regulation to regulation Controller Top part Extension modules A regulation with few connections can be performed with the controller module alone If there are many connections one ...

Page 5: ... into a network together with other controllers in an ADAP KOOL refrigeration control system After the setup operation can be performed at a distance with say our software program type AKM Users The controller comes supplied with several languages one of which can be selected and employed by the user If there are sev eral users they may each have their choice of language All users must be assigned...

Page 6: ... define the measurements you wish to be shown The collected values can be printed or you may export them to a file You can open the file in Excel If you are in a service situation you can show measurements in a trend function The measurements are then made real time and displayed instantly Alarm The display gives you an overview of all active alarms If you wish to confirm that you have seen the al...

Page 7: ...rt 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 part may be sufficient If it is an application with many connections it will be necessary to use the controller module plus one or more extension modules This section will give you a survey of possi...

Page 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 switches another may receive a voltage signal and a third type may be outputs with relays etc The individual types are shown in the table below Optional connection When a regulation is planned set up it w...

Page 9: ...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 Display EKA 164B Display with operation buttons EKA 166 Display with operation buttons and LED for function cut in MMIGRS2 Graphic display with operation Cable between display and controller Length 2 m 6 m Cable between g...

Page 10: ...Min 24 V Max 230 V Low and high voltage must not be connected to the same output group Solid state outputs Can be used for loads that are cut in and out frequently e g Fans and AKV valves Max 240 V a c Min 48 V a c Max 0 5 A Leak 1 mA Max 1 AKV Stepper outputs Used for valves with stepper input 20 500 step s Separate supply to stepper outputs 24 a c d c xx VA Ambient temperature During transport 4...

Page 11: ...102 Danfoss 2017 07 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 length of an aggregate unit n x 72 8 ...

Page 12: ...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 communication cable the gateway must have knowledge of the new controller This is obtained by pushing the key PIN The LED Status will flash when the gateway sends an acceptance message Operation The configuration operat...

Page 13: ... 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 40 41 17 DO6 42 43 44 18 DO7 45 46 47 19 DO8 48 49 50 24 25 Terminal 15 12 V Terminal 16 5 V Terminal 27 12 V Terminal 28 5 V Terminal 17 18 29 30 Cable screen Solid state outputs on 12 15 Relay or AKV coil fx ...

Page 14: ...t 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 depending on transmitter type Light emitting diodes Only the two top LED s are used They indicate the following Voltage supply to the module Communication with the controller is active red error ...

Page 15: ... P0 Pc Pgc Prec Paux AKS 32R AKS 2050 MBS 8250 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 1 2 3 4 Type AI1 AI2 AI3 AI4 Terminal 9 12 V Terminal 10 5 V Terminal 15 5 V Terminal 16 12 V Terminal 11 12 13 14 Cable screen At the top the signal input is the left of the two terminals At the bot...

Page 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 comes from the previous module in the row Light emitting diodes They indicate Voltage supply to the module Communication with the controller is active red error Status of the individual inputs 1 to 8 wh...

Page 17: ...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 off Point 5 6 7 8 Type DI5 DI6 DI7 DI8 Point 1 2 3 4 Type DI1 DI2 DI3 DI4 AK XM 102A Max 24 V AK XM 102B Max 230 V The module can not register a pulse signal from e g a reset function ...

Page 18: ...om 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 inputs are galvanically separated from the outlets The outlets AO1 and AO2 are galvanically separated from AO3 and AO4 Light emitting diodes Only the two top LED s are used They indicate the following Voltage supp...

Page 19: ... Pgc Prec Paux AKS 32R AKS 2050 MBS 8250 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 Terminal 11 12 Cable screen Galvanic isolation AI 1 4 AO 1 2 AO 3 4 Point 5 6 7 8 Type AO1 AO2 AO3 AO4 Point 1 2 3 4 Type AI1 AI2 AI3 AI4 3 Brown 2 Blue 1 Black 3 Brown 2 Black 1 Red At the top the signal...

Page 20: ...nt make it possible to over ride the relay s function Either to position OFF or ON In position 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 red error Status of outputs DO1 to DO8 Right row AK XM 204B only Override of relays ON override OFF no override...

Page 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 valve On Off Point 1 2 3 4 5 6 7 8 Type DO1 DO2 DO3 DO4 DO5 DO6 DO7 DO8 ...

Page 22: ... of relay Eight change over switches at the front make it possible to over ride the relay s function Either to position OFF or ON In position 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 red error Status of outputs DO1 to DO8 Right row AK XM 205B only...

Page 23: ...gnal type S Pt 1000 ohm 0 C Ss Sd Shr Sgc Sc3 Saux_ Pt 1000 P AKS 32R AKS 32 P0 Pc Pgc Prec Paux AKS 32R AKS 2050 MBS 8250 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 DO Comp Fan Alarm Solenoid valve Active at on Off Terminal 9 12 V Terminal 10 5 V Terminal 21 12 V Terminal 22 5 V Terminal 11 12 23 24 Cable screen Point 9 10 11 1...

Page 24: ...s 7 8 VA for controller xx VA per valve A UPS may be necessary if the valves need to open close during a power failure Light emitting diodes There is one row with LED s It indicate the following Voltage supply to the module Communication active with the bottom PC board red error Step1 to step4 OPEN Green Open Step1 to step4 CLOSE Green Close Red flash Error on motor or connection Output 24 V d c 2...

Page 25: ... ETS White Black Red Green CCM CCMT KVS 15 White Black Green Red KVS 42 54 CCM CCMT Valve Module Step Terminal 1 point 9 25 28 2 point 10 29 32 3 point 11 33 36 4 point 12 37 40 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 Point 9 10 11 12 Step 1 2 3 4 Type AO ...

Page 26: ...The 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 module Point The two outputs have points 24 and 25 They are shown on the earlier page where the controller is also mentioned Max load I 2 5 mA R 4 kohm ...

Page 27: ...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 output B etc Placing The extension module can be placed at a distance of up to 15 m from the controller module Point No point has to be defined for a display module you simply con nect it Graphic display MMIGRS2 Function Setting and display of value...

Page 28: ...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 ...

Page 29: ...be connected to the communication 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 terminals must not be earthed The power consumption is determined by the power consump tion of the total number of modules The controller strand load must not exceed 32 VA Each ...

Page 30: ... the controller is linked up in a network with a system manager Start stop of regulation Regulation can be started and stopped via the software External start stop can also be connected Warning The function stops all regulation including any high pressure regulation Excess pressure can lead to a loss of charge Start stop of compressors External start stop can be connected Alarm function If the ala...

Page 31: ...ltage inputs DI This signal must be connected to two terminals The signal must have two levels either 0 V or voltage on the input There are two different extension modules for this signal type low voltage signals e g 24 V high voltage signals e g 230 V When programming the function must be set Active when the input is without voltage Active when voltage is applied to the input Limitations As the s...

Page 32: ...d regulation x Step and speed regulation x Speed regulation first step x Limitation of speed during night operation x Heat recovery function for domestic water or room x Gas cooler pressure reference Floating pressure reference x Setting of references for heat recovery functions x Design of a compressor and condenser control Procedure 1 Make a sketch of the system in question 2 Check that the cont...

Page 33: ...t Day night signal for raising the suction pressure The clock function can be used but an external ON OFF signal may be used instead If the P0 optimization function is used no signal will be given concerning the raising of the suction pressure The P0 optimiza tion will see to this Inject ON override function The function closes expansion valves on evaporator controls when all compressors are preve...

Page 34: ...lation Pgc with reference from Sc3 and Sgc Pressure increase for heat recovery Data from this example is used on the next page The result is that the following modules should be used AK PC 772A controller AK XM 208C stepper output module AK XM 103A analog input and output module On off outputs Relay outputs Compressors Unloaders Fan motor Injection On function signal for evaporator controls One pe...

Page 35: ...verter Max 1 fan External start stop Night setback of suction pressure Separate alarm functions via DI Load shedding Start of Heat recovery On off outputs Compressors motors 5 Unloaders Fan motors circulation pumps 1 Alarm relay I m alive relay Inject ON Max 2 Separate thermostat and pressostat functions and voltage measure ments Max 1 1 1 Heat recovery function via thermostat 1 Max 1 Liquid injec...

Page 36: ...er there is connection 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 DIN rail no matter where in the row the module is found Removal is likewise carried out with the two catches in the open position Length If you use many extension modules the controlle...

Page 37: ...MT 6 AI 6 11 12 AKS 2050 59 Condensing pressure Pc MT 7 AI 7 13 14 AKS 2050 159 8 AI 8 19 20 Suction gas temperature Ss LT 9 AI 9 21 22 Pt 1000 Discharge temperature Sd LT 10 AI 10 23 24 Pt 1000 Suction pressure P0 LT 11 AI 11 25 26 AKS 2050 59 Compressor 1 MT 12 DO 1 31 32 ON Compressor 2 MT 13 DO 2 33 34 ON Compressor 3 MT 14 DO 3 35 36 ON Compressor 1 LT 15 DO 4 37 38 ON Compressor 2 LT 16 DO 5...

Page 38: ...s of the individual modules may be ordered from Danfoss Format dwg and dxf You may then yourself write the module number in the circle and draw the individual connections The supply voltage for the pressure transmitter should be taken from the same module that receives the pressure signal ...

Page 39: ...AK PC 772A Capacity controller RS8HF102 Danfoss 2017 07 39 Example continued ...

Page 40: ...ed via the plug between the modules The supply must be 24 V 20 One power supply must be used for each controller The power supply must be a class II The 24 V must not be shared by other controllers or units The analog inputs and outputs are not galvanically separated 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 se...

Page 41: ...le There is only room for one module AK OB 110 2 080Z0251 Type Function Application Code no Example continued Operation AK ST 500 Software for operation of AK controllers AK operation 080Z0161 x Cable between PC and AK controller USB A B standard IT cable x Accessories Power supply module 230 V 115 V to 24 V d c AK PS 075 18 VA Supply for controller 080Z0053 x x AK PS 150 36 VA 080Z0054 AK PS 250 ...

Page 42: ...42 Capacity controller RS8HF102 Danfoss 2017 07 AK PC 772A ...

Page 43: ...section describes how the controller 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 772A controller module AK XM 208C analog input module stepper output module AK XM 103A analog input and output module ...

Page 44: ...ng Mounting of analog output module 1 Lift the top part off the basic module The basic module must not be connected to voltage Press in the plate 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 module 3 Put the top part back on the basic module There...

Page 45: ... basic module 1 Move the protective cap Remove the protective cap from the connection plug on the right hand side of the basic module Place the cap on the connection plug to the right of the exten sion module that is to be mounted on the extreme right hand side of the AK assembly 2 Assemble the extension module and the basic module The basic module must not be connected to voltage When the two sna...

Page 46: ...0 Suction pressure P0 LT 11 AI 11 25 26 AKS 2050 59 Compressor 1 MT 12 DO 1 31 32 ON Compressor 2 MT 13 DO 2 33 34 ON Compressor 3 MT 14 DO 3 35 36 ON Compressor 1 LT 15 DO 4 37 38 ON Compressor 2 LT 16 DO 5 39 40 41 ON Valve and circulation pump HR 17 DO6 42 43 44 ON Fan motors 18 DO7 45 46 47 ON Hot gas dump 19 DO8 48 49 50 ON 24 25 Signal Module Point Step Terminal Signal type Compressor 1 MT G...

Page 47: ...ounting 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 same module that receives the pressure signal Warning Keep signal cables separate from cables with high voltage ...

Page 48: ...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 configured Power Comm DO1 Status DO2 Service Tool DO3 LON DO4 I O extension DO5 Alarm DO6 DO7 Display DO8 Service Pin Internal communication between the modules Quick flash error Constantly On error Status on output 1 8 Mo...

Page 49: ... 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 3 compressors for MT and 2 compressors for LT and high pressure control using heat recovery and gas cooler The example is shown two pages in ...

Page 50: ...er an overview of it will always appear In 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 alarm in the controller In our case the alarm is due to the fact that the time in the controller has not yet been set For connecting and operating the AK service tool software please see the manual for ...

Page 51: ...s with Cyclical One speed controlled Safety monitoring of each compressor Common high pressure monitoring P0 setting 10 C P0 optimisation LT circuit 2 x compressors with Cyclical One speed controlled Safety monitoring of each compressor Common high pressure monitoring P0 setting 30 C P0 optimisation Gas cooling control Fans speed controlled Pressure regulation Pgc with reference from Sc3 and Sgc P...

Page 52: ... 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 language If the language is not contained in the controller the settings and readings will be shown in English When the controller is supplied it has been set with standard authoriza tion for different u...

Page 53: ...Go to Configuration menu 2 Select Lock Unlock configuration 3 Select Configuration lock Press the blue field with the text Locked 4 Select Unlocked Select Unlocked The controller can only be configured when it is unlocked The values can be changed when it is locked but only for those settings that do not affect the configuration ...

Page 54: ...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 controller s address When the time is set the PC s time can be transferred to the controller When the controller is connected to a net work date and time will automatically be set by the system unit in the network This also applies...

Page 55: ...T Select compressor application for IT External main switch A switch may be connected for starting and stopping the regulation Mon Ext Power loss signal from an UPS Monitoring of external voltage When selecting yes a digital input is allocated Alarm output Here you may set whether or not it should be an alarm relay and which priorities will activate it I m alive relay A relay will release if the r...

Page 56: ... 25 C Min permissible suction pressure reference 4 Compressor application Select the compressor application required Lead compressor type For LT only Variable The following options are available for variable No of compressors Set number of compressors Total max 2 if parallel compressor is also selected No of unloaders Set number of unloader valves Ext compressor stop An external switch can be conn...

Page 57: ...on time for PI regulation Zone acceleration A Higher values result in a faster regulation Zone acceleration A Higher values result in a faster adjustment Advanced settings Select whether the advanced capacity control settings should be visible T0 filter Reduce changes in the Po reference Pc filter Reduce changes in the Pc reference Minimize cycling The control zone may vary for connections and dis...

Page 58: ...xceeded the entire compressor capacity will be cutout Tc max limit Limit value read in C Pc Max delay Time delay for the alarm Pc max T0 Min limit Minimum value for the suction pressure in C If the limit is reduced the entire compressor capacity will be cutout T0 Max alarm Alarm limit for high suction pressure P0 T0 Max delay Time delay before alarm for high suction pressure P0 Safety restart time...

Page 59: ...n if a liquid injection is required in the suction line in order to keep the discharge gas tempera ture down Regulation can be done either using a solenoid valve and a TEV or using an AKV valve AKV OD suction line Opening degree of the valve in Inject start SH Superheat value where the liquid injection starts Inject diff SH Differential when adjusted for superheat Inject start Sd temp Start temper...

Page 60: ... group LT Set control of LT compressors Configuration continued In principle the functions are the same as for MT In principle the same settings are carried out but in the LT group it will be possible to select compressors with variable capacity For the IT group the compressors must be speed controlled ...

Page 61: ...ed The fan capacity is controlled via a combination of speed control and step coupling Speed The fan capacity is controlled via speed control frequency converter Speed 1 step First fan speed controlled rest step coupling No of fans Set number of fans Monitoring fan safety Safety monitoring of fans A digital input is used to monitor each fan Fan speed type VSD and normal AC motors EC motor DC contr...

Page 62: ...and control The P band is 100 Kp PI Control The fan capacity is regulated by the PI controller Kp Amplification factor for PI controller Tn Integration time for PI controller Capacity limit at night Setting of maximum capacity limit during night operations Can be used to limit fan speed at night in order to limit the noise level Configuration continued ...

Page 63: ...city offset Adjust how much the pressure shall be increased by when the function Extra capacity offset is activated Pgc min Min acceptable pressure in the gas cooler Pgc max Max acceptable pressure in the gas cooler Advanced settings Vhp min OD Restriction of the valve s degree of closing Vhp max OD Restriction of the valve s degree of opening Pgc max limit P band P band under Pgc max where the va...

Page 64: ... with the External compressor stop function Prec min limit P band P band under Prec min where the ICMTS valve s degree of opening is increased Prec max limit P band P band over Prec max where the ICMTS valve s degree of opening is decreased Monitor liquid level Choose whether liquid level should be monitored Liquid alarm delay Time delay for the alarm Use hot gas dump Select whether hot gas should...

Page 65: ... control Yes Here the controller must receive a voltage signal or a temperature signal from an external source The offset values that apply to the max value must be defined Input type select Temperature control A signal from a temperature sensor must be received Set the reference temperature Consumer A 0 10 V or 0 5 V signal must be received Control type Regulation with external offset select P or...

Page 66: ... example separate displays 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 P0 in bar Ss Sd Cond control sensor Tc Pc bar Sgc Pgc bar Prec bar Trec Speed Compressor Unit readout Choose whether readings are to be in SI units C and bar or US units F and psi Configuration continued ...

Page 67: ...3 Define number of required functions In our example we do not use functions for general purposes so the picture is included for orientation Each function is described on the following pages The following number of different functions can be defined 1 thermostat 1 pressostat 1 voltage signal 10 alarm signals 1 PI regulation Configuration continued ...

Page 68: ...lways shown in overview display 2 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 outlet Cut out temp Cut out value for the thermostat Cut in temp Cut in value for the thermostat High alarm limit High alarm limit Alarm delay high Time delay for high alarm Alarm text high Indicate ala...

Page 69: ... voltage signal The function has a separate outlet to control external automatic controls Settings Show on overview Name Select sensor signal voltage Select the signal which the function should use Actual value read out of the measurement Actual state read out of outlet status Min readout State read out values at minimum voltage signal Max readout State read out values at maximum voltage signal Cu...

Page 70: ...erature pressure pressure converted to temperature voltage signal Tc Pc Ss DI etc Setpoint If fixed reference is choosen 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 Alarm mode Choose whether an alarm shall be attached to the function If it is set to ON alarm texts and alarm limit...

Page 71: ...ns the earlier settings will require The tables are the same as shown earlier 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 connected to We furthermore select for each output whether the function is to be ac tive when the output is in pos Closed or Open Ope...

Page 72: ... temp Pc Cond Pres Sc3 air on Ext Ref Signal 0 5 V 0 10 V HP control Pgc Prec Sgc Shr Saux 1 Paux 1 Voltage input 1 0 5 V 0 10 V 1 5 V 2 10 V PI in temp PI ref temp PI in voltage PI in pres PI ref pres Function Output Module Point Type Stepper signal for by pass valve CCM Step 1 2 9 CCM Stepper signal for high pressure valve CCMT Step 3 2 11 CCMT Speed control compressor MT AO1 3 5 0 10 V Speed co...

Page 73: ... 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 priority Disconnected gives no action The interdependence between setting and action can be seen in the table In our example we select the settings shown here in the display Configuration continued Setting Log Ala...

Page 74: ...HF102 Danfoss 2017 07 AK PC 772A Press the button to go on to the next page 5 Set alarm priorities for thermostat and extra digital signals In our example we select the settings shown here in the display Configuration continued ...

Page 75: ...ake 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 Press in the field against Configuration lock Select Locked The setup of the controller has now been locked If you subsequently want to make any changes in the controller s setup remember first to unlock the configuration Configuration continued ...

Page 76: ...he 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 that the setup must be unlocked be fore you can change module and point numbers The settings are shown on a RED background If a setting has turned red you must control the setup again This may be due to the following The input or the output has...

Page 77: ...nfiguration of Analog Outputs Press the button to go on to the next page 6 Check configuration of Analog Inputs The setup of the analog outputs appears as it is supposed to according to the wiring made The setup of the analog inputs appears as it is supposed to according to the wiring made Configuration continued ...

Page 78: ...s 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 the manual control of each output it can be checked whether the output has been correctly connected Cut out the safety circuit for compressor 1 Check that LED DI1 on the extension module module 2 g...

Page 79: ...en 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 has not been connected The sensor is short circuited The point or module number has not been set up correctly The configuration is not locked Set Control of output voltage to manual Press in the Mode field Select MAN Press in the Va...

Page 80: ...ttom of the pages the ones that can only be seen via the Scroll bar 4 Check the individual pages 5 Go back to the overview Repeat for LT Before the control starts we check that all the settings are as they should be The overview display will now show one line for each of the general functions Behind each icon there is a number of displays with the different settings It is all these settings that h...

Page 81: ...ay 1 have been re viewed it is time to look at the General functions in overview display 2 Press the button to access The first is the thermostat group Check the settings 11 Then the pressure switch group Check the settings 12 Proceed with the remaining functions 13 The controller setup has been completed The last page contains reference settings Check of settings continued All the defined general...

Page 82: ... schedule function for the night setback of the suction pressure In other cases where the controller is installed in a network with one system unit this setting may be made in the system unit which will then transmit a day night signal to the controller Press a weekday and set the time for the day period Continue with the other days A complete weekly sequence is shown in the display ...

Page 83: ...nt at 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 unit Depending on the size of the network it may be up to one minute before the controller receives an answer as to whether it has been installed in the network When it has been installed the Sta...

Page 84: ... list 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 relevant In our case an active alarm remains because the control has stopped This alarm must be active when control has not started We are now ready for the startup of control Please note that active plan...

Page 85: ...e bottom of the display 2 Start control Press in the field against Main switch Select ON The controller will now start controlling the compressors and the fans Note Control does not start until both the internal and external switch are ON Any external compressor stop breaker must be ON for the compressors to start First start of control continued ...

Page 86: ...apacity 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 compressors the oil management will be shut down This could cause compressor damages If the wiring of the compressors includes safety relays monitoring will continue See Regulating functions Press the ...

Page 87: ...AK PC 772A Capacity controller RS8HF102 Danfoss 2017 07 87 5 Regulating functions This section describes how the different functions work ...

Page 88: ...t can be activated in three ways Signal on an input From a master gateway s override function Internal time schedule The night displacement function should not be used when regulation with the override function P0 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 1...

Page 89: ...sic rules Increase capacity The capacity distributor will start extra compressor capacity as soon as the requested capacity has increased to a value which allows the next compressor step to start Referring to below example a compressor step is added as soon as there is Room for this compressor step below the requested capacity curve Decrease capacity The capacity distributor will stop compressor c...

Page 90: ...ressor is prevented from starting because it is hanging on the restart timer or is safety cut out this step is replaced by another compressor Operating time equalisation The operating 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 first At the differe...

Page 91: ...same frequency range For cyclical coupling patterns the two speed regulated compressors should be the same size and the subsequent one step compressor should also be the same size The following is a description of some general rules for handling capacity regulated compressors speed regulated compressors and also for two speed regulated compressors Capacity regulated compressors with unload valves ...

Page 92: ...t 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 set so high that a fast lubrication of the compressor is obtained during the start Controlling increasing capacity If the need for capacity becomes larger than Max Speed then the subsequent compres...

Page 93: ...following 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 compressor with a nominal capacity at 50Hz of 20kw Variable speed range 25 50Hz 2 one step compressors of 20 kW Fixed capacity 25 HZ 50 HZ x 20 kW 10 kW Variable capacity 25 HZ 50Hz x 20 kW 10 kW The capaci...

Page 94: ...at max speed and the desired 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 step compressors will be cut in and out in accordance with the selected coupling pattern Controlling decreasing capacity The speed regulated compressors will always be th...

Page 95: ...is registered continuously The number of starts can be read out here Number during the previous 24 hour period Total number since the counter was last set to zero set Two independent speed regulated compressors If the two speed regulated compressors need to be controlled asynchronously they must each have their own analogue voltage signal The controller first starts one of the speed regulated comp...

Page 96: ...h two unloaders 4 cylinder version The compressor capacity can be controlled from 10 to 100 depending on the pulsation of the unloaders The compressor start signal is connected to a relay output and the unloaders are connected to fx DO1 and DO2 Unloader 2 follows unloader 1 but it remains displaced by a half period Unloader 1 Unloader 2 CRII 6 The pulse signal can also be used to control one CRII ...

Page 97: ...elay time for each digital inlet If the suction pressure during load shedding exceeds the set overriding limit and the attached delay times for the two digital inlets expire then load shedding overrides the signals so that the compressor capacity can be increased until the suction pressure is again under the normal reference value The load shedding can then be activated again Alarm When a load she...

Page 98: ...ons cuts out 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 valve The pulse width modulating signal for the AKV valve shall be taken from one of the controller s four solid state outputs Time delay A time delay can be set which ensures that the injec...

Page 99: ... at 130 C 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 limit can be defined in the range from 120 to 30 C The suction is measured with pressure transmitter P0 At cutout the alarm function is activated The alarm is cancelled and renewed cutin of com...

Page 100: ...the outlet for the gas cooler Cap Ctrl sensor Sgc Pc is used as the safety function for high condenser pressure and will therefore ensure cut out of the compressor capacity when condenser pressure is too high Handling sensor errors In the event of Sgc failure the controller switches over to an emergency cooler sequence that attempts to maintain regula tion Reference for condensing pressure The ref...

Page 101: ...mal operating conditions the temperature at Sd will be be tween 60 and 70 C depending on whether it is winter or summer If the Heat reclaim function is to raise the condensing pressure the temperature may increase to 90 or higher The Sc3 sensor should be positioned so that it measures the air intake temperature for the gas cooler If it measures a temperature that is too high the system s COP will ...

Page 102: ...signal from for example a building management system When the function is activated the reference for the condenser temperature will be raised to a set value and the attached relay outlet is used to activate valve and pump 2 Use of a thermostat for the function This function can be used with advantage where the heat recovery is used to warm up a water tank A temperature sensor is used to activate ...

Page 103: ...On Off Pgc HR min fan HR min Yes Temperature control On Off Temperature sensor Pgc HR min fan HR min HR reference temperature Pgc HR offset fan HR offset Consumer signal On Off 0 10 V Pgc HR min fan HR min Pgc HR offset fan HR offset Increasing pressure reference with heat recovery Heat recovery is initiated with an On signal when the thermostat calls for heat or a DI signal is received Without HR...

Page 104: ...ed regulation All fans will now be regulated from 0 to max capacity If an ON OFF signal is required for the frequency converter so that the fans can be stopped completely a relay output can be defined The controller starts the frequency converter when the capacity requirement corresponds to the set starting speed The controller stops the frequency converter when the capacity requirement becomes lo...

Page 105: ...hour period total operating time since the timer was last set to zero set Coupling counter The number of couplings is registered continuously Here the number of starts can be read out number during the previous 24 hour period total number since the counter was last set to zero set Exercising fans The last fans are unlikely to be activated during winter months To ensure that the fans are exercised ...

Page 106: ...operation without override the controller will maintain the optimum pressure in the transcritical area Warning Remember that the controller controls the gas pressure If the regulation is stopped by the internal or external main switch this control will stop as well Risk of loss of charge If the compressors are stopped via the function External com pressor stop control of the gas pressure will cont...

Page 107: ...nitions Fixed setpoint Displacement of the setpoint with an external signal Optimisation where the IT circuit maintains pressure at the most energy efficient level Delta P where the reference is a pressure difference between the receiver and Po on the MT circuit P band There are two safety functions for the receiver They are only available for gas cooled regulation A P belt must be installed to be...

Page 108: ...egularly records the opening degree of the Vrec valve When the opening degree is greater than the set value the IT compressor will start up But it only starts up if the temperature at Sgc is higher than the set value in IT setting IT Comp Sgc min The controller will now speed regulate the IT compressor so that the pressure in the receiver is kept at the desired level The parameter IT comp delay de...

Page 109: ...e respectively including separate alarm delays The individual pressure control function can be adapted to the relevant application as it is possible to give the pressure control a name and indicate alarm texts General voltage input with ancillary relay 1 unit A voltage input are accessible for monitoring a measurement of the installation Examples are monitoring of a leak detector moisture measurem...

Page 110: ...process is quick more careful setup is required A general balancing 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 fluctuating and is constantly fluctuating Adjust Kp to half the value Adjust Tn down until the process starts fluctuating again Adjust Tn to do...

Page 111: ...m If necessary use the necessary safety signals to ensure that the controller receives signals about discon nections Sensor calibration The input signal from all connected sensors can be corrected A correction will only be necessary if the sensor cable is long and has a small cross sectional area All displays and functions will reflect the corrected value Clock function The controller contains a c...

Page 112: ...quently 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 from the gateway s forced operation function via data communication When the forced operation function asks about one change all the connected controllers on this network will be set simultaneously Th...

Page 113: ...apacity setting for suction group 0 MAN 1 OFF 2 AUTO r23 MT Set point suction pressure Setting of required suction pressure reference in C r24 MT Suction pressure reference Actual reference temperature for compressor capacity r12 Main switch 0 Controller stopped 1 Regulating r28 Set point condenser Setting of required condenser pressure in C r29 Condenser reference Actual reference for temperature...

Page 114: ...n the modules Quick flash error Constantly On error Status of output 1 8 Network installation Graphic display MMIGRS2 With the display is access to most of the controller functions For access connect the display to the controller and activate the address on MMIGRS2 A separate power supply does not need to be connected Power is supplied directly from the controller via the cable Setting 1 Press bot...

Page 115: ...s stationary If required this current ensures that the valve main tains its last programmed position This value is limited to a range of 0 70 given in 10 steps Overdrive at Valve Init During valve initialization the amount to overdrive the valve beyond the 0 position to ensure that the valve has fully closed This value is limited to a range of 0 31 Phase Current The current applied to each phase o...

Page 116: ...om extra Temp sensor Saux_ is defective Paux_ sensor error Signal from extra pressure sensor Paux_ is defective All compressors Common safety High Common compr Safety cutout All compressors have been cut out on common safety input Comp 1 safety Comp 2 safety Comp 3 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 Compress...

Page 117: ... System alarms The alarm priority can not be altered on system alarms Control mode Low Manual comp cap Control A Compressors capacity control runs i manual mode Control mode Low Manual cond cap Control A Condense capacity control runs i manual mode Refrigerant changed Low Refrigerant changed Refrigerant type has been changed Medium Time has not been set Time has not been set Medium System Critical...

Page 118: ...ty to check the installation thoroughly and to fit the necessary safety devices Special reference is made to the necessity of signals to the controller when the compressor is stopped and to the need of liquid receivers before the compressors Your local Danfoss agent will be pleased to assist with further advice etc Danfoss can accept no responsibility for possible errors in catalogues brochures an...

Reviews: