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High effi ciency condensing unit OEM user manual NO POWER & SIGNAL CABLES TOGETHER READ CAREFULLY IN THE TEXT! I n t e g r a t e d C o n t r o l S o l u t i o n s & E n e r g y S a v i n g s...
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The technical specifi cations shown in the manual may be changed without prior warning. The liability of CAREL in relation to its products is specifi ed in the CAREL general contract conditions, available on the website www.carel.com and/ or by specifi c agreements with customers; specifi cally, to the extent where allowed by applicable legislation, in no case will CAREL, its employees or subsidiaries/affi...
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Hecu CO +0300085EN rel. 2.2 - 07.05.2019...
Content 1. INTRODUCTION 1.1 General features ....................7 1.2 Components and accessories ..............7 2. INSTALLATION 2.1 Main board: description of the terminals ..........8 2.2 10A single-phase inverter ................9 2.3 12-16 A single-phase, 18-24 A three-phase inverter ......10 2.4 12 A single-phase inverter PSD2 ...............
1. INTRODUCTION 1.1 General features 1.2 Components and accessories Hecu CO2 is a control system for complete management of R744 Part number Description condensing units fi tted with BLDC compressors. The serial connection A ECU70TS0C0 Hecu CO2 controller, 230Vac, RTC, 2 unipolar EEV,...
J15. Digital Type: digital inputs with voltage-free contacts 1 optional line (J13), selectable from the Carel options available inputs Number of digital inputs (DI): 4 Max. connection cable length: 2 m via unshielded cable, 500 m via Analogue Type: 0 to 10 Vdc cont., PWM 0 to 10 V 50 Hz synch.
CE conformity: 2.2 10A single-phase inverter 2006/95/EC For further details on the electrical and mechanical specifi cations, see EN 61800-5-1: Adjustable speed electrical power drive systems. Safety require- technical leafl et +0500076IE ments. Electrical, thermal and energy. 2004/108/EC EN 61800-3, ed. 2.0: Adjustable speed electrical power drive systems. EMC require- ments, including specifi...
CE conformity: 2.3 12-16 A single-phase, 18-24 A three- 2006/95/EC phase inverter EN 61800-5-1: Adjustable speed electrical power drive systems. Safety require- ments. Electrical, thermal and energy. For further details on the electrical and mechanical specifi cations, see 2004/108/EC technical leafl et +0500048IE EN 61800-3, ed.
System: loss of communication, Safety: STO (Safe Torque Off ), locked rotor Control unit Each drive must be connected in the network via Modbus® to a CAREL pCO or other manufacturer’s controller that manages the drives with Master/ Slave logic. Inputs Voltage-free contact input, reinforced insulation (12 V SELV circuit): open contact voltage: <24 V...
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Interface RS485, Modbus® protocol, maximum baud rate 19200 bit/s - typical resistance in reception 96 KΩ (equal to Serial data connection 1/8 load unit, i.e. 1/256 of the maximum load applicable on the line) data connection Insulation Reinforced (24 V SELV circuit) Maximum length 100 m shielded cable Ingress protection...
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System: loss of communication, Safety: STO (Safe Torque Off ), locked rotor Control unit Each drive must be connected in the network via Modbus® to a CAREL pCO or other manufacturer’s controller that manages the drives with Master/Slave logic. Inputs Voltage-free contact input, reinforced insulation (24 V SELV circuit): open contact voltage: <24 V...
CAREL EEV electronic expansion valve. The confi guration defi ned for medium temperature applications involves Hecu CO2 managing a DC compressor, with up to 2 on-off fans, an electronic expansion valve for gas cooler pressure control (HPV) and an electronic expansion valve for managing receiver pressure (RPRV). The...
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3. Serial network confi guration Hecu CO2 is fi tted with a built-in RS485 Fieldbus serial port and optional RS485 BMS serial port. The RS485 Fieldbus serial line can be connected to 2 Power+ inverters and up to 5 MPXPRO/UltraCella controllers. The addresses are defi...
Note: serial connection starts from terminal J10 on Hecu CO2 and runs through the power+ inverter and all the MPXPRO controllers installed on the refrigerated units. The maximum number of MPXPRO controllers is 5, the limit for this application.
3.1 Graphic terminal An example of the menu screens is shown in the fi gure: The Hecu CO2 user interface is the pGDE terminal, in the panel or built- in version. The functions associated with the 6 buttons on the pGDE terminal are the same on all screens, and are described in the table.
4. MENU DESCRIPTION 4.1 Main menu To navigate the menu tree, use the following a.Main Info b.Setpoint buttons: A.Unit Status c.ON/OFF a.Status a.Dig.In. b.Analog In. c.Dig.Out d.Analog Out b.Manual man. a.Dig.Out b.Analog Out c.usc.BLDC d.vacuum c.Test a.Dig.Out • & : navigate sub-menus, screens and B.Input/Output b.Analog Out ranges of values and settings;...
5.1 Guided commissioning procedure set as default by CAREL based on the type of application and the Hecu CO2 can be setup the fi rst time from the pGDe or pLDpro user refrigerant. The type of control is always proportional and integral, terminal.
Digital input screen Cag01. On-off from the user terminal and the confi guration parameters are Hecu CO2 and power+ must be powered and connected via serial; the available under the main menu, branch Ac address of power+ must be 1 (default).
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The logic is described in the following graph: Comp Start-up Hecu CO2 manages compressor start-up in the best way possible, adapting operating speed so as to guarantee that the desired conditions and excellent lubrication are reached very quickly. For this reason, when starting the compressor is operated at a settable fi...
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Hecu CO2 stops the compressor and generates a "No compressor start- up” alarm. This alarm is automatically reset and Hecu CO2 tries to start the compressor fi ve times after a 30 second delay. After the fi fth attempt the alarm is no longer automatically reset.
DSH control Screen Cag44 is used to deactivate the function based on the outside/ Hecu CO2 controls superheat on the compressor discharge line at the ambient temperature; if "COMP OFF" mode is selected on screen Cag43. same time as superheat on the suction line.
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This software function is available by exploiting serial communication screen. with the evaporators. Serial communication allows information to be exchanged in real time between the main Hecu CO2 controller and the MPXPRO devices. Note: the MPXPRO controllers installed on the evaporators implement the Smooth Lines function (see MPXPRO manual +0300055).
DSS3: screen Fib04 Start the parallel compressor (L1) when starting the LT compressor (L2). If NO is selected, the parallel compressor cannot start without a request. The function can be deactivated when at least one of the following conditions is true: Compressor control OFF Active compressor alarms When DSS1 is enabled, the following parameters remain hidden on...
Analog output Max capacity = 100% Max output Hecu CO2 can manage up to two fans with a speed modulation device, value = 10 V which may be an inverter or a PWM phase control device. In the same way as for the compressors, fan control can be proportional or proportional plus integral, based on pressure or temperature.
Cut-off Floating Hecu CO2 manages a cut-off control function for the fans; the function setpoint can be enabled and the related parameters set in main menu branch Setpoint Db05. The operating principle of the cut-off function is shown in the fi...
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Hecu unit. This is exploited when integrated drivers for the oil valve cannot be used on Hecu CO2 as they are reserved for transcritical valves. Valve opening is calibrated based on the BLDC compressor operating conditions (MT or LT, not parallel), adjusted proportionally based on compressor speed.
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Fixing time function Fig. 6.t Note: this function will be less eff ective than the one Carel provides Washing of individual cabinets can be confi gured exclusively in sequential via serial connection of the evaporators managed by MPXPRO and mode.
OFF, which can be set by parameter. When The HPV valve can be managed directly by Hecu CO2 via the driver a compressor restarts, valve control resumes, with the pre-positioning integrated into the controller.
Fha06 Digital outputs inside the CO receiver at the set point. Parameters The RPRV valve can be managed directly by Hecu CO2 via the driver Fhb01 Enable HPV valve management, i.e. enable tran- integrated into the controller. scritical operating mode...
Control Fhb25 receiver pressure set point Hecu CO2 can manage up to fi ve stage functions, with either direct or Proportional gain for proportional + integral reverse operation. In both cases, a set point and a diff erential can be...
Saving and restoring user default values Hecu CO2 can save on the controller the exact confi guration set by the user and then reload it at any time. All of the set values are saved, therefore loading the user defaults restores the exact same conditions of the Hecu CO2 controller at the moment the values were saved.
7. FAST COMMISSIONING Once the condensing unit has been confi gured, the MPXPRO/UltraCella controllers installed on the evaporators then need to be confi gured, and subsequently the entire system representing the combination of both. The Fast Commissioning function is an automatic procedure that assists the installer in the fi...
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Prg/mute for 5 s to exit the guided commissioning procedure. P1: Type of electronic expansion valve MPXPRO can control the CAREL E V electronic expansion valve. The CAREL electronic expansion valve is required for the Hecu CO2, and therefore this parameter must always be set to “2”. Par. Description Electronic valve Fig.
MPXPRO 1 This parameter tells the Master controller how many Slave controllers it MPXPRO 2 needs to manage in the local network. Hecu CO2 only accepts MPXPRO MPXPRO 3 MPXPRO 4 master controllers, therefore this parameter must always be set to “0”.
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Commissioning with UltraCella Service terminal Parameters Modification Password: 1234 Multifunction menu HACCP UltraCella with LED display UltraCella Service terminal Fig. 7.g 2. To enter Programming mode: press Prg and enter the password: 1234 Fig. 7.c Parameters Categ. 1/16 If the UltraCella controller has never been confi gured, as soon as the terminal is connected, the wizard is shown automatically.
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While the other parameters that select the protocol are: Par. Description • H7 = 0 Carel protocol B2 confi guration • H7 = 1 Modbus protocol Absent H7 must be = 1, while the other parameters retain the default settings,...
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Probe reading correction Function of digital inputs DI1, DI2 and DI3 The values read by the probes can be corrected by adding or subtracting PARAMETERS A11, A5, A9 an off set from the measurement, set by parameters /c1 to /c5. Selection Contacts Par.
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Application: an external device is used to start the defrost (on closing the digital input) and subsequently stop it (on opening the digital input). When the digital input opens, the dripping time set for parameter dd Timer must then elapse. UNIT 1 Note: Defrost...
Typeof valve Door switch + light button Carel exv If A4 = 1, the light is switched on/off only by the light button. The door Type of refrigerant status, open or closed, is ignored. If A4 = 0, when the cold room door R744 is open, the light is always on.
7.4 Connecting MPXPRO/Ultracella Par. Description Washing cycle duration 180sec controllers to Hecu tOFF Time between two washing cycles 180min Mode One cabinet at a time Sequential or together Once having completed the confi guration of the MPXPRO/UltraCella Fixing time Stabilisation time after washing 120sec controllers, the serial network needs to be connected, as shown in the Tab.
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Smooth Lines function Electronic valve control The superheat control function calculates the valve position based on the The smooth lines function optimises evaporator capacity based on current superheat reading and the set point. PID control (Proportional, actual cooling demand, allowing more eff ective and stable control of the Integral, Derivative) is the sum of three distinct actions: showcase.
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LowSH Low superheat protection. To prevent too low superheat values that may cause the return of liquid to the compressor or system instability (swings), a low superheat threshold can be defi ned, below which a special protection function is activated. When the superheat falls below the threshold, the system immediately enters low superheat status and activates an integral control action, which added to normal control is aimed at closing the electronic valve more...
8. SIGNALS AND ALARMS Hecu CO2 can manage both alarms relating to the status of the digital inputs and to system operation. For each alarm, the following are The alarm log can be accessed: controlled: • from branch H.a of the main menu •...
8.3 Pressure alarms descriptions from other groups can be selected for that alarm. Hecu CO2 can manage pressure alarms from a pressure switch or probe, For example, the selection may be generic, or alternatively overload + oil. according to the following diagram.
Pressure alarms from probe 8.5 High pressure prevention The parameters corresponding to these alarms can be set in branch C.a.e Hecu CO2 can manage the high discharge pressure prevention actions, of the main menu for suction pressure, and D.a.e for condensing pressure. involving: •...
8.7 Alarm table Screen Display Description Serious Alarm Delay Reset index alarm ALU02 Control probe absent At least one of the main probes is not confi gured Not present Auto correctly: P_suc, P_GC, T_out_GC, P_ric ALA01 Discharge temperature probe broken Compressor discharge temperature probe Not present Auto...
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Action Troubleshooting Unit switched off Check control probes * No control action Check T_dis probe * Corresponding functions disabled: - T_dis control by Hb02 - speed control based onT_dis by Hb03 No control action Check P_GC probe * The HPV valve is set to a safety percentage on Fhb13 Corresponding functions disabled: Check T_out * - control switches to T_out in case of P_GC fault on...
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Screen Display Description Serious Alarm Delay Reset index alarm ALB15 High suction pressure Suction pressure exceeds a threshold set on Cae24 Cae25 Auto ALB16 Low suction pressure Suction pressure below a settable threshold Cae27 Auto ALB22 Oil sensor level broken Oil level sensor faulty or not confi...
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Action Troubleshooting • Check correct compressor operation (presence of liquid, excessive refrigerant charge, compressor sizing,..) • Evaporators with valves fully open at the same time (e.g. MOP set incorrectly on MPXPRO, valves stuck open,..) Compressor shutdown, set on Cae27 • Check correct compressor operation (incorrect sizing, low refrigerant charge,..) •...
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Store 1…5: Incorrect setting of parameter P1 on MPXPRO 1 to 5, from MPXPRO 89-ALZ02 stepper driver communication error which must be set to 2 (management of Carel E2V (P1) electronic valve is required) ALW51-64-77- Store 1…5: stepper motor error...
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• Check parameter P1 (this must be set to 2) on MPXPRO in relation to the valve installed on the evaporator (this must - No action be the Carel E2V electronic valve) Signal-only alarm Check electronic valves on the respective cabinets...
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Screen Display Description Serious Alarm Delay Reset index alarm ALP04 Parallel compressor envelope alarm Compressor operation outside of the envelope Cbg55 Auto ALP05 Parallel compressor high discharge The parallel compressor discharge temperature exceeds Not settable Auto gas temperature a certain threshold set on Hb04 ALP06 Parallel compressor low pressure Diff...
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Action Troubleshooting Compressor shutdown, with speed reduction set on • Check positioning, installation and correct operation of P_GC probe (positioning before the check valve at the com- Cbg54 pressor discharge, checking the values are read correctly) • Check positioning, installation and correct operation of P_ric probe; 8 operating zones outside of envelope •...
9. SOFTWARE UPDATE 9.1 Uploading/updating the software The key is factory-programmed in read/write mode (type C) so that it can be used immediately to transfer software from one controller to another. The following methods can be used to update the fi rmware and acquire When the key is connected to the personal computer, the symbols have the log fi...
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1tool programming environment. Fig. 9.f Installing pCOmanager Go to http://ksa.carel.com, and in the pCO sistema section select pCO_ Commissioning manager. After accepting the general terms and conditions for the free software license, a window will open for downloading the pCO_manager.
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Changing a parameter Support fi les Choose the category of parameters and then the parameter to be set: this At the end of the application program design phase, 1tool generates is highlighted by a blue line (e.g. recovery.recovery_type). several fi les during compilation; two of these are required for commissioning: •...
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