Carel EVD mini User Manual

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EVD mini

Superheat control for unipolar electronic expansion valve

User manual

High Efficiency Solutions

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ENG

WARNINGS

CAREL bases the development of its products on decades of experience in HVAC, on the continuous investments in technological innovations to products, procedures and strict quality processes with in-circuit and functional testing on 100% of its products, and on the most innovative production technology available on the market. CAREL and its subsidiaries nonetheless cannot guarantee that all the aspects of the product and the software included with the product respond to the requirements of the ﬁnal application, despite the product being developed according to start-of-theart techniques. The customer (manufacturer, developer or installer of the ﬁnal equipment) accepts all liability and risk relating to the conﬁguration of the product in order to reach the expected results in relation to the speciﬁc ﬁnal installation and/or equipment. CAREL may, based on speciﬁc agreements, acts as a consultant for the positive commissioning of the ﬁnal unit/application, however in no case does it accept liability for the correct operation of the ﬁnal equipment/system.

The CAREL product is a state-of-the-art product, whose operation is speciﬁed in the technical documentation supplied with the product or can be downloaded, even prior to purchase, from the website www.carel.com. Each CAREL product, in relation to its advanced level of technology, requires setup/conﬁguration/programming/commissioning to be able to operate in the best possible way for the speciﬁc application. The failure to complete such operations, which are required/indicated in the user manual, may cause the ﬁnal product to malfunction; CAREL accepts no liability in such cases. Only qualiﬁed personnel may install or carry out technical service on the product. The customer must only use the product in the manner described in the documentation relating to the product.

In addition to observing any further warnings described in this manual, the following warnings must be heeded for all CAREL products:

• prevent the electronic circuits from getting wet. Rain, humidity and all

types of liquids or condensate contain corrosive minerals that may damage the electronic circuits. In any case, the product should be used or stored in environments that comply with the temperature and humidity limits speciﬁed in the manual;

• do not install the device in particularly hot environments. Too high

temperatures may reduce the life of electronic devices, damage them and deform or melt the plastic parts. In any case, the product should be used or stored in environments that comply with the temperature and humidity limits speciﬁed in the manual;

• do not attempt to open the device in any way other than described in the

manual;

• do not drop, hit or shake the device, as the internal circuits and mechanisms

may be irreparably damaged;

• do not use corrosive chemicals, solvents or aggressive detergents to clean

the device;

• do not use the product for applications other than those speciﬁed in the

technical manual.

DISPOSAL

INFORMATION FOR USERS ON THE CORRECT

HANDLING OF WASTE ELECTRICAL AND ELEC-

TRONIC EQUIPMENT (WEEE)

In reference to European Union directive 2002/96/EC issued on 27 January 2003 and the related national legislation, please note that:

1. WEEE cannot be disposed of as municipal waste and such waste must be collected and disposed of separately;

2. the public or private waste collection systems deﬁned by local legislation must be used. In addition, the equipment can be returned to the distributor at the end of its working life when buying new equipment;

3. the equipment may contain hazardous substances: the improper use or incorrect disposal of such may have negative eﬀects on human health and on the environment;

4. the symbol (crossed-out wheeled bin) shown on the product or on the packaging and on the instruction sheet indicates that the equipment has been introduced onto the market after 13 August 2005 and that it must be disposed of separately;

5. in the event of illegal disposal of electrical and electronic waste, the penalties are speciﬁed by local waste disposal legislation.

Warranty on the materials: 2 years (from the date of production, excluding consumables).

Approval: the quality and safety of CAREL INDUSTRIES products are guaranteed by the ISO 9001 certiﬁed design and production system, as well as by the marks (*).

All of the above suggestions likewise apply to the controllers, serial boards, programming keys or any other accessory in the CAREL product portfolio. CAREL adopts a policy of continual development. Consequently, CAREL reserves the right to make changes and improvements to any product described in this document without prior warning. The technical speciﬁcations shown in the manual may be changed without prior warning.

The liability of CAREL in relation to its products is speciﬁed in the CAREL general contract conditions, available on the website www.carel.com and/or by speciﬁc agreements with customers; speciﬁcally, to the extent where allowed by applicable legislation, in no case will CAREL, its employees or subsidiaries be liable for any lost earnings or sales, losses of data and information, costs of replacement goods or services, damage to things or people, downtime or any direct, indirect, incidental, actual, punitive, exemplary, special or consequential damage of any kind whatsoever, whether contractual, extra-contractual or due to negligence, or any other liabilities deriving from the installation, use or impossibility to use the product, even if CAREL or its subsidiaries are warned of the possibility of such damage.

CAUTION: separate as much as possible the probe and digital input signal cables from the cables carrying inductive loads and power cables to avoid possible electromagnetic disturbance. Never run power cables (including the electrical panel wiring) and signal cables in the same conduits.

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“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

Content

1. INTRODUCTION 7

1.1 Models ............................................................................................................... 7

1.2 Functions and main characteristics .............................................................7

1.3 Accessories ....................................................................................................... 7

2. INSTALLATION 8

2.1 Dimensions and mounting-mm (in) .......................................................... 8

2.2 Description of the terminals ......................................................................... 9

2.3 Wiring diagram for superheat control ...................................................... 10

2.4 Installation ...................................................................................................... 10

2.5 Copy parameters with programming key ................................................ 11

3. USER INTERFACE 12

3.1 Keypad.............................................................................................................12

3.2 Display ............................................................................................................. 12

3.3 Programming mode .....................................................................................12

3.4 Restore factory parameters (default) ........................................................12

ENG

4. COMMISSIONING 13

5. FUNCTIONS 15

5.1 Control ............................................................................................................. 15

5.2 Analogue positioner (0-10 Vdc) ................................................................. 16

5.3 Superheat control with 2 temp. probes ................................................... 16

5.4 Special functions ............................................................................................17

5.5 Regolazione speciale: smooth lines ...........................................................17

5.6 Control parameters for protection functions .......................................... 18

5.7 Service parameters .......................................................................................18

6. PROTECTORS 19

6.1 Protectors ........................................................................................................ 19

7. PARAMETERS TABLE 21

8. NETWORK CONNECTION 23

8.1 RS485 serial conﬁguration .......................................................................... 23

8.2 Network connection for commissioning via PC .....................................23

8.3 Visual parameter manager ..........................................................................23

8.4 Restore default parameters .........................................................................24

8.5 Setup by direct copy .....................................................................................24

8.6 Setup using conﬁguration ﬁle ....................................................................25

8.7 Read the conﬁguration ﬁle on the controller ..........................................25

8.8 Variables accessible via serial connection ...............................................26

8.9 Control states .................................................................................................27

8.10 Special control states ....................................................................................28

9. ALARMS 30

9.1 Types of alarms ..............................................................................................30

9.2 Probe alarms ..................................................................................................30

9.3 Control alarms ...............................................................................................30

9.4 Valve emergency closing procedure .........................................................30

9.5 Network alarm ............................................................................................... 31

9.6 Alarm table ..................................................................................................... 31

10. TROUBLESHOOTING 32

11. TECHNICAL SPECIFICATIONS 34

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1. INTRODUCTION

ENG

EVD mini is a range of drivers designed for the control of CAREL singlepole electronic expansion valves used in refrigerant circuits. EVD mini controls refrigerant superheat and optimises refrigerant circuit performance; it guarantees signiﬁcant system ﬂexibility being compatible with various types of refrigerants, in applications with refrigerators and chiller/air-conditioners. It features low superheat protection (LowSH), high evaporation pressure (MOP) and low evaporation pressure (LOP) functions.

As regards network connectivity, the driver can be connected via serial RS485/ Modbus® to:

• a pCO programmable controller

• a CAREL supervisor.

Another possibility involves operation as a simple positioner with 0 to 10 Vdc analogue input signal, or as a manual positioner via RS485. EVD mini can be supplied with LED display for information on the instant superheat value and any active alarms, or for performing the commissioning operations. The latter involves setting just three parameters: refrigerant, operating mode (showcase, air conditioner, etc.) and superheat set point.

The driver can also be setup using a computer via the serial port. In this case, the VPM program (Visual Parameter Manager) needs to be installed, downloadable from http://ksa.carel.com, and the USB-RS485 converter connected.

1.1 Models

P/N Description

EVDM001N00 EVD mini 24 V with display EVDM000N00 EVD mini 24 V without display EVDM010N00 EVD mini 115/230 V without display EVDM011N00 EVD mini 115/230 V with display

Tab. 1.a

1.2 Functions and main characteristics

In summary:

• superheat control with LowSH, MOP, LOP functions;

• compatibility with various types of refrigerants;

• guided setup procedures ﬁrst, entering just three parameters on the

user interface: refrigerant (Gas), type of control (Mode) and superheat set point (Superheat);

• activation/deactivation of control via digital input or remote control

via serial connection;

• controller and valve power supply incorporated (230 V/115 V);

• RS485 serial communication incorporated (Modbus protocol);

• IP65;

• operating conditions: -25T60C° (-13T140°F);

• compatible with Carel E2V and E3V single-pole valves.

From software revision 1.6 and higher, new functions have been introduced:

• hot gas bypass by pressure;

• hot gas bypass by temperature.

The ratiometric pressure probe speciﬁed as default for assembly is P/N SPKT0013P0, with an operating range from -1 to 9.3 barg. Alternatively, other probes can be installed, setting the corresponding parameter accordingly. See the “Functions” chapter..

P/N Type P/N Type

SPKT0053P0 -1…4.2 barg SPKT00B6P0 0…45 barg SPKT0013P0 -1…9.3 barg SPKT00E3P0 -1…12.8 barg SPKT0043P0 0…17.3 barg SPKT00F3P0 0…20.7 barg SPKT0033P0 0…34.5 barg

Tab. 1.b

Single-pole valve (P/N E2V**F**C1/ E3V**B**C1)

Fig. 1.b

Ultracap module (P/N EVDMU**N**)

The module guarantees temporary power to the driver in the event of power failures, for enough time to immediately close the connected electronic valve. It avoids the need to install a solenoid valve. The module is made using Ultracap storage capacitors, which ensure reliability in terms of much longer component life than a module made with lead batteries.

Fig. 1.c

Ferrite (P/N 0907879AXX)

Clamp-on ferrite for use in certain applications. See the technical speciﬁcations table.

Fig. 1.d

Programming key with power supply (P/N IROPZKEYA0)

The key can be used to quickly program the controllers, reducing the risk of errors. This accessory also allows fast and eﬀective technical service, and can be used for programming the controllers in just a few seconds, also during the testing phase.

The smooth lines function has been introduced starting from software revision 1.8.

1.3 Accessories

Pressure probe cable (see technical leaﬂet +050000484), pressure probe (-1…9.3 barg, P/N SPKT0013P0) and temperature probe (P/N NTC006HP0R).

Fig. 1.a

Fig. 1.e

USB/RS485 converter (P/N CVSTDUMOR0)

The converter ensures connection between the computer used for conﬁguration and the EVD mini driver.

Fig. 1.f

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ENG

2. INSTALLATION

2.1 Dimensions and mounting-mm (in)

Mounting

EVD mini (24 V) YES YES EVD mini (230 V) YES NO

(3.7)

(3.4)

(2.8)

(3.9)

on DIN rail: with screws

EVD mini (24 V)

GAS Type

Mode

Super Heat

BASSO/ BOTTOM

60 (2.4)

74,1 (2.9)

88 (3.5)

33 (1.3)

On DIN rail mounting:

1. Fasten the DIN rail and ﬁt the controller from point

2. 24V model: use a screwdriver to remove the two side slots before

installing any other controllers alongside.

EVD mini (24 V)

ype

GAS

Mode

Super He

Fig. 2.c

EVD mini (230 V)

;

117 (4.60)

113,7 (4.48)

Fig. 2.a

EVD mini (230 V)

GAS Type

Mode

Super Heat

70,7 (2.78)

Fig. 2.b

BASSO/ BOTTOM

42,7 (1.68)

Type

GAS

Mode

Super He

Fig. 2.d

Screw mounting

On the wall, mark the positions of the holes as per the ﬁgure and drill the holes (Ø < 4mm). Then tighten the fastening screws.

GAS Type

Mode

Super Hea

72 (2.8)

Ø 4 (0.2)

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

74,10 (2.9)

Fig. 2.e

2.2 Description of the terminals

EVD mini 24 V EVD mini (230 V)

ENG

CAREL E2 V/ E3V unipolar valve

0,3 Nm

A B C D

NTC

ULTRACAP Module

ratiometric pressue

transducer

NTC

CAREL E2 V/ E3V unipolar valve

0,3 Nm

Ferrite/ Ferrite bead

cod. 0907879AXX

+13V (in)

+13V (out)

GND

Signal

GND

GAS Type

Mode

Super Heat

VPM

CVSTDUM0R0

Modbus®

RS485

pCO

shield

GND

Tx/Rx+

Tx/Rx-

shield

24 Vac

GND

5Vref

Signal

digital input to start the regulation

24 Vdc

20 VA

230 Vac

Ferrite/ Ferrite bead

cod. 0907879AXX

VPM

CVSTDUM0R0

Modbus®

RS485

pCO

shield

ULTRACAP Module

GND

Tx/Rx+

C D

GAS Type

Mode

Super Heat

Tx/Rx-

shield

NTC

+13V (in)

+13V (out)

ratiometric pressue

transducer

GND

Signal

GND

S2 S1

D I

the regulation

230 Vac

digital input to start

NTC

5Vref

GND

Signal

Fig. 2.f Fig. 2.a

Key:

Ref. Terminal Description Ref. Terminal Description

ExV Single-pole valve connection +13 V (in)

+13 V (out) DI Digital input to enable control

Ultracap module connection (accessory)

GND Signal S2 probe (temperature) N 230 V power supply, neutral

Ground Earth for S2 probe DI 230 V digital input to enable control

(24 Vdc power supply)

(230 V power supply)

GND Earth for S1 probe

G Power supply, 24 Vdc G0 Power supply, 0 Vdc

L 230 V power supply, line

GND

Terminal for RS485 connection5Vref Power S1 active probe Tx/ Rx +

Signal S1 probe: pressure or temperature Tx/ Rx -

(24 Vac power supply)

- Connection as positioner (0 to 10 V input)

Connection for superheat control with 2 temperatu-

re probes G Power supply, 24 V ac G0 Power supply, 0 V ac

DI Digital input to enable control

PC for conﬁguration

USB – RS485 Converter

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

Tab. 2.a

ENG

2.3 Wiring diagram for superheat control

• EVD mini requires the use of an evaporation pressure probe S1 and

suction temperature probe S2, which will be ﬁtted downstream of the evaporator, and a digital input to enable control. Alternatively, the signal to enable control can be sent via a remote RS485 connection;

• input S1 is programmable and connection to the terminals depends

on the parameter settings. See the chapters “Commissioning” and “Functions”.

Note: for details on installing probes, see the “EEV system guide”

(+030220810).

CAREL E2 V/ E3V unipolar valve

0,3 Nm

GAS Type

2 1

2.4 Installation

For installation, proceed as shown below, with reference to the wiring diagrams and the technical speciﬁcations table:

1. connect the probes: these can be installed up to a maximum

distance of 10 m from the driver; select the pressure probe suitable for the refrigerant. For details on the recommended pressure probe for each refrigerant, see “Commissioning”;

2. connect any digital inputs, maximum length 10 m;

3. connect the valve cable: it is recommended to use a maximum cable

length of 1 m for E2V and E3V valves.

4. the 24 V models can be powered at:

• 24 Vac: use a class II safety transformer, adequately protected against

short-circuits and overload. Transformer power must be between 20 and 50 VA, as shown in the technical speciﬁcations table;

• 24 Vdc: use an external power supply, the see technical

speciﬁcations table;

5. the connection cables must have a minimum cross-section of 0.35 mm

6. power on the driver: the LED on the power supply/display comes

on and the driver will be immediately operational, with the default parameters: a. Refrigerant = R404A; b. Type of control: multiplexed showcase/cold room; c. Superheat set point = 11 K.

7. program the driver, if necessary: see the “User interface” chapter;

8. connect to the serial network where required. See the following diagrams

for connecting the earth on the 24 V EVD mini models.

EVD mini 24 Vac in serial network

Case 1: multiple drivers connected in a network, inside the same electrical panel, powered by the same transformer

;

Mode

Super Heat

GND

Tx/Rx+

Tx/Rx-

pCO

GND

Tx/Rx+

Tx/Rx-

VPM

CVSTDUM0R0

230 Vac

24 Vdc

20 VA

24 Vac

Case 2: multiple drivers connected in a network, inside diﬀerent electrical

digital input to start

the regulation

panels with the same earth point

GND

Tx/Rx+

Tx/Rx-

pCO

Important: Earthing of G0 and G in driver EVD mini 24 Vac

GND

Tx/Rx+

Tx/Rx-

Fig. 2.h

24 Vac

20 VA

GND

Tx/Rx+

Tx/Rx-

Fig. 2.i

230 Vac

24 Vac

230 Vac

20 VA

connected in serial network brings to permanent damage of the driver.

Fig. 2.g

Key:

Ratiometric pressure transducer – evaporation pressure

NTC – suction temperature

Digital input to enable control

Personal computer for conﬁguration

USB / tLAN converter

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

GND

Tx/Rx+

Tx/Rx-

pCO

24 Vac

20 VA

GND

Tx/Rx+

Tx/Rx-

230 Vac

24 Vac

NO!

230 Vac

20 VA

Fig. 2.j

ENG

Installation environment

Important: avoid installing the drivers in environments with the

following characteristics:

• relative humidity greater than 90% or with condensation;

• strong vibrations or knocks;

• exposure to continuous water sprays;

• exposure to aggressive and polluting atmospheres (e.g.: sulphur

and ammonia fumes, saline mist, smoke) to avoid corrosion and/or oxidation;

• strong magnetic and/or radio frequency interference (therefore avoid

installing the devices near transmitting antennae);

• exposure of the driver to direct sunlight and to the elements in general.

Important: the following warnings must be observed when

connecting the driver:

• if the driver is used in a way that is not speciﬁed in this user manual,

protection cannot be guaranteed;

• incorrect power connections may seriously damage the driver;

• use cable ends suitable for the corresponding terminals. Loosen each

screw and insert the cable ends, then tighten the screws and gently tug the cables to check they are suﬃciently tight;

• separate as much as possible (at least 3 cm) the probe and digital

input cables from power cables to avoid possible electromagnetic disturbance. Never run power cables (including the electrical panel cables) and probe signal cables in the same conduits;

• do not run probe signal cables in the immediate vicinity of power

devices (contactors, circuit breakers, etc.). Reduce the path of probe cables as much as possible, and avoid spiral paths that enclose power devices;

• avoid powering the controller directly from the main power supply in

the panel if this supplies diﬀerent devices, such as contactors, solenoid valves, etc., which will require a separate transformer;

• *EVD mini/ice is a controller to be incorporated into the ﬁnal

equipment; it must not be wall-mounted;

• * DIN VDE 0100: protective separation must be guaranteed between

the SELV circuits (Safety Extra Low Voltage) and the other circuits. The requirements of DIN VDE 0100 must be complied with. To prevent disruption of the protective separation (between the SELV circuits and the other circuits) ensure additional fastening near the terminations. This additional fastening must secure the insulation and not the wires.

EVD mini (24 V)

Important: do not use a screwdriver to remove the cover on the

display, to avoid damaging the board.

To remove the cover of the display:

Apply a pressure rightward on the left side of the cover.

Raise up the right side to extract it.

Plug the key into the provided connector, then perform the desired

operation (UPLOAD/DOWNLOAD).

GAS Type

press

Mode

Super Heat

EVD mini (230 V)

To remove the cover of the display:

Press with a screwdriver as shown in the ﬁgure, to remove the cover.

Lift the cover and remove it.

Plug the key into the provided connector, then perform the

desired operation (UPLOAD/DOWNLOAD).

press

Fig. 2.l

GAS

Mode

Super Heat

ype

2.5 Copy parameters with programming key

Note:

• The parameters must only be copied when the driver is NOT powered;

• also see the programming key technical leaﬂet, P/N +050003930.

Procedure: A. Open the cover on the key using a screwdriver; B. Set the microswitches based on the operation :

- UPLOAD: microswitches 2 = OFF,

- DOWNLOAD: microswitches 1= OFF, microswitches 2 = ON See leaﬂet +050003930

Fig. 2.k

press

ype

GAS T

Mode

Super He

press

ype

GAS

Mode

Super Heat

Fig. 2.m

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

3. USER INTERFACE

On models where featured, the user interface comprises the twodigit display and keypad with three buttons that, pressed alone or in combination, are used to perform all the conﬁguration and programming operations on the driver.

Model without display

Fig. 3.a

Red LED - see “Alarms”

Green LED - power supply ON

Model with display

GAS Type

Mode

Super Heat

Fig. 3.b

Key

Parameter label (for commissioning)

Keypad

Control ON/OFF digital input status LED

ﬂashing/oﬀ = DI closed/open (*) Two-digit display

(*) when the digital input is closed, the LED ﬂashes and control is activated.

During commissioning/setup, the parameter label shows the meaning of the segments displayed in the ﬁrst digit, corresponding to the three parameters being set:

A. GAS Type: type of refrigerant; B. Mode: operating mode; C. Superheat: superheat set point.

See the “Commissioning” chapter.

Mode

GAS Type

Super Heat

GAS Type

Mode

Super Heat

GAS Type

Mode

Super Heat

A. Refrigerant B. Mode (operating mode) C. Superheat set point

3.1 Keypad

Key Description

UP DOWN

PRG/Set

• Increases/decreases the value of the set point or other

selected parameter

• menu navigation

• at the end of the commissioning procedure, press for 2 s to

exit and activate control;

• enter/exit control mode, saving the parameters;

• reset alarm E8

Tab. 3.b

3.2 Display

During normal operation, the two-digit display shows the superheat measure and any alarms. If used as an analogue positioner, it displays the 0 to 10 V input value with decimal point. The display interval for the superheat value is -5 to 55 K (-9 to 99 °F). In general, values between -99 and 999 are displayed as follows:

1. values from 0 to 10 are displayed with decimal point and decimals;

2. values greater than 99 are displayed in two steps:

- ﬁrst, the hundreds, followed by “H”

- then the tens and units.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

3. values less than -9 are displayed in two steps:

- ﬁrst the “-“sign;

- then the tens and units.

123 --->

-99 --->

GAS Type

Mode

Super Heat

GAS Type

Mode

Super Heat

GAS Type

Mode

Super Heat

GAS Type

Mode

Super Heat

Fig. 3.c

3.3 Programming mode

The parameters can be modiﬁed using the front keypad. Access depends on the user level: basic parameters (ﬁrst conﬁguration/setup) and Service parameters (Installer).

Important: DO NOT change the control parameters before

completing the commissioning wizard, as described in chapter 4.

Modifying the Service parameters

The Service parameters include, in addition to the parameters for the conﬁguration of input S1, those corresponding to the network address, probe readings, protectors and manual positioning. See the param. table. Procedure:

1. press UP and DOWN together and hold for more than 5 s: the ﬁrst

parameter is displayed: P1 = probe S1 reading;

2. press UP/ DOWN until reaching the desired parameter;

3. press PRG/ Set to display the value;

4. press UP/ DOWN to modify the value;

5. press PRG/ Set to conﬁrm and return to the parameter code;

6. repeat steps 2 to 5 to modify other parameters;

7. (when the parameter code is displayed) press PRG/Set and hold for

more than 2 s to exit the parameter setting procedure.

GAS Type

Mode

Super Heat

Fig. 3.d

Note: if no button is pressed, after around 30 s the display

automatically returns to standard visualisation.

3.4 Restore factory parameters (default)

It is possible restore the controller to the default settings. Procedure: with the controller in standard display mode, press the three buttons together. After 5 seconds the display shows “rS”. The reset procedure can be conﬁrmed within 10 seconds, by pressing PRG/SET buttons for 3 seconds. If no button is pressed during this time, the procedure will be cancelled. At the end, the controller displays two dashes and then awaits the commissioning parameters.

4. COMMISSIONING

ENG

Note:

• If the controller does not have a display, see “Network connection”;

• the default pressure probe is the ratiometric probe, with a measurement

range of -1…9.3 barg;

• note the unit of measure (K/°F) when setting the superheat set point. To

change the unit of measure, see the “Functions” chapter.

4.1 Commissioning procedure

Once the electrical connections have been completed (see the chapter “Installation”) and the power supply has been connected, the operations required for commissioning the driver depend on the type of interface used, however essentially involve setting just 3 parameters: refrigerant,

functioning mode, superheat setpoint.

Important:

• until the commissioning procedure has been completed, control will not be active;

• (only during commissioning) changing the refrigerant also means having to change the type of pressure probe.

Power on the driver: the display lights up and the driver awaits the commissioning parameters, as indicated by the bar on the display:

1. Refrigerant (default = 3: R404A);

2. Type of control (default = 1: multiplexed showcase/cold room);

3. Superheat set point (default= 11 K).

Procedure:

4. Press PRG to save the setting and return to the refrigerant parameter

code (bar at top)

GAS Type

Mode

Super Heat

5. Press DOWN to move to the next parameter: Mode, indicated by the

bar in the middle.

6. Repeat steps 2-4 to set superheat settings 1-7 and bypass 8-9;

GAS Type

Mode

Super Heat

7. Press DOWN to move to the next parameter. For the superheat set

point, the bar at the bottom is shown. Set the superheat set point;

GAS Type

Mode

Super Heat

1. The display shows the bar at the top: refrigerant (GAS Type)

GAS Type

Mode

Super Heat

2. Press PRG/Set to display the refrigerant setting

GAS Type

Mode

Super Heat

3. Press UP/DOWN to modify the value

GAS Type

Mode

Super Heat

8. In the event of bypass control by pressure, parameter _P is shown.

Set the bypass pressure set point.

GAS Type

Mode

Super Heat

9. In the event of bypass control by temperature, parameter _t is

shown. Set the bypass temperature set point.

GAS Type

Mode

Super Heat

10. Press PRG/Set for 2 s to save the settings, exit programming mode and activate control. The standard display is shown.

Mode

Super Heat

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

4.5 Initial conﬁguration parameters

Important: ONLY DURING COMMISSIONING, changing the refrigerant also means having to change the type of ratiometric probe; if not speciﬁed in the table, the ratiometric probe type is (-1 ... 9.3 barg).

Refrigerant

Parameter/ description Def.

Gas Type = refrigerant

0 = Custom

1 R22 15 R422D 29 R455A (-1...12.8 barg) 2 R134a 16 R413A 30 R170 (0...17.3 barg) 3 R404A 17 R422A 31 R442A (-1...12.8 barg) 4 R407C 18 R423A 32 R447A (-1...12.8 barg) 5 R410A 19 R407A 33 R448A 6 R507A 20 R427A 34 R449A 7 R290 21 R245FA 35 R450A (-1...4.2 barg) 8 R600

(-1...4.2 barg)

9 R600a

(-1...4.2 barg) 10 R717 24 HTR01 38 R452B 11 R744

(0...45 barg) 12 R728 26 R23 40 R454B 13 R1270 27 R1234yf 14 R417A 28 R1234ze (-1...4.2

22 R407F 36 R452A (-1...12.8 barg)

23 R32

(0...17.3 barg)

25 HTR02 39 R513A (-1...4.2 barg)

barg)

37 R508B (-1...4.2 barg)

3 = R404A

Note: if the refrigerant gas is not among those selectable for the

“GAS Type = refrigerant” parameter:

1. set any refrigerant (e.g. R404);

2. select the type of main control, the superheat set point and complete

the initial commissioning procedure;

3. use the VPM program (Visual Parameter Manager, see the chapter

“Network connection”) and set the type of refrigerant: “0 = custom” and the “Dew point a...f high/low” parameters that deﬁne the refrigerant;

4. start control, for example by closing the digital input contact.

Operating mode

Mode = Operating mode

1 Multiplexed showcase/cold room 2 Air-conditioner/chiller with plate heat exchanger 3 Air-conditioner/chiller with tube bundle heat exchanger 4 Air-conditioner/chiller with ﬁnned coil heat exchanger 5 Analogue positioner (0 to 10 V) 6 Superheat control with 2 temperature probes 7 Subcritical CO2 showcase/cold room 8 Hot gas bypass by pressure 9 Hot gas bypass by temperature

1 = Multiplexed showcase/ cold room

Set point

Note: take into consideration the unit of measure (K/°F) when

setting the superheat set point.

Superheat set point 11 K(20°F) Bypass pressure set point 3 bar Bypass temperature set point 10 °C

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

5. FUNCTIONS

5.1 Control

EVD mini is a superheat controller and can be used as an analogue positioner. The type of refrigeration unit can be selected using the “Operating mode” parameter.

ENG

Parameter/description Def.

Operating mode

1 Multiplexed cabinet/cold room 2 Air-conditioner/chiller with plate heat exchanger 3 Air-conditioner/chiller with tube bundle heat exchanger 4 Air-conditioner/chiller with ﬁnned coil heat exchanger 5 Analogue positioner (0 to 10 V) 6 Superheat control with 2 temperature probes 7 Subcritical CO2 showcase/cold room 8 Hot gas bypass by pressure 9 Hot gas bypass by temperature

1 = multiplexed cabinet/cold room

Tab. 5.a

Based on the operating mode setting , the driver automatically sets a series of control parameters.

Operating mode PID:

1 Multiplexed cabinet/cold room 15 150 11 5 15 -50 0 50 20 2 Air-conditioner/chiller with plate heat exchanger 3 40 6 2 2,5 -50 4 50 10 3 Air-conditioner/chiller with tube bundle heat

exchanger

4 Air-conditioner/chiller with ﬁnned coil heat

exchanger 5 Analogue positioner (0 to 10 V) - - - - - - - - 6 Superheat control with 2 temperature probes 15 150 11 5 15 -50 0 50 20 7

Subcritical CO2 showcase/cold room 8

Hot gas bypass by pressure 9

Hot gas bypass by temperature

proport. gain

5 60 6 2 2,5 -50 4 50 10

10 100 6 2 10 -50 10 50 20

20 400 13 7 15 -50 0 50 20

PID: integration time

20 200 - - - - - - - 3 15 150 - - - - - - - - 10

Superheat set point

LowSH protection

th-

Integra-

reshold

tion time

LOP protection MOP protection Bypass

threshold

Integration time

threshold

Integration time

pres-

sione:

setpoint

(bar)

Bypass

tempe-

ratura:

setpoint

(°C)

Tab. 5.b

Superheat

The primary purpose of the electronic valve is ensure that the ﬂow-rate of refrigerant that ﬂows through the nozzle corresponds to the ﬂow-rate required by the compressor. In this way, the evaporation process will take place along the entire length of the evaporator and there will be no liquid at the outlet (consequently in the branch that runs to the compressor). As liquid is not compressible, it may cause damage to the compressor and even breakage if the quantity is considerable and the situation lasts some time.

Superheat control

The parameter that the control of the electronic valve is based on is the superheat temperature, which eﬀectively tells whether or not there is liquid at the end of the evaporator. The superheat temperature is calculated as the diﬀerence between: superheated gas temperature (measured by a temperature probe located at the end of the evaporator) and the saturated evaporation temperature (calculated based on the reading of a pressure transducer located at the end of the evaporator and using the Tsat(P) conversion curve for each refrigerant).

(*)

Superheat = Superheated gas temperature

temperature

(*) suction

If the superheat temperature is high it means that the evaporation process is completed well before the end of the evaporator, and therefore ﬂow-rate of refrigerant through the valve is insuﬃcient. This causes a reduction in cooling eﬃciency due to the failure to exploit part of the evaporator. The valve must therefore be opened further.

– Saturated evaporation

The valve must therefore be closed further. The operating range of the superheat temperature is limited at the lower end: if the ﬂow-rate through the valve is excessive the superheat measured will be near 0 K. This indicates the presence of liquid, even if the percentage of this relative to the gas cannot be quantiﬁed. There is therefore un undetermined risk to the compressor that must be avoided. Moreover, a high superheat temperature as mentioned corresponds to an insuﬃcient ﬂow-rate of refrigerant. The superheat temperature must therefore always be greater than 0 K and have a minimum stable value allowed by the valve-unit system.

A low superheat temperature in fact corresponds to a situation of probable instability due to the turbulent evaporation process approaching the measurement point of the probes. The expansion valve must therefore be controlled with extreme precision and a reaction capacity around the superheat set point, which will almost always vary from 3 to 14 K. Set point values outside of this range are quite infrequent and relate to special applications.

Vice-versa, if the superheat temperature is low it means that the evaporation process has not concluded at the end of the evaporator and a certain quantity of liquid will still be present at the inlet to the compressor.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

EVD mini

Fig. 5.a

Key

CP compressor EEV electronic expansion valve C condenser V solenoid valve L liquid receiver E evaporator F dewatering ﬁlter P pressure probe (transducer) S liquid indicator T temperature probe

For the wiring, see “Wiring description”.

PID parameters

Superheat control uses a PID algorithm. The control output is calculated as the sum of separate contributions: proportional and integral.

• the proportional action opens or closes the valve proportionally to

the variation in the superheat temperature. Thus the greater the K (proportional gain) the higher the response speed of the valve. The proportional action does not consider the superheat set point, but rather only reacts to variations. Therefore if the superheat value does not vary signiﬁcantly, the valve will essentially remain stationary and the set point cannot be reached;

• the integral action is linked to time and moves the valve in proportion

to the deviation of the superheat value from the set point. The greater the deviations, the more intense the integral action; in addition, the lower the value of Ti (integral time), the more intense the action will be. The integral time, in summary, represents the intensity of the reaction of the valve, especially when the superheat value is not near the set point.

See the “EEV system guide” +030220810 for further information on calibrating PID control.

5.2 Analogue positioner (0-10 Vdc)

The valve will be positioned linearly depending on the value of the “0 to 10 V input for analogue valve positioning” read by input S2. There is no PID control nor any protection (LowSH, LOP, MOP), and no valve unblock procedure. The opening of digital input DI stops control, and consequently forces the valve closed, switching operation to standby.

0 ...10 Vdc

EVD mini

100%

010

regulator

Vdc

Fig. 5.b

Key:

EV Electronic valve A Valve opening

For the wiring see chap. 2: “Description of the terminals”.

Important: the pre-positioning and re-positioning procedures will not be performed. Manual positioning can in any case be enabled when control is active or in standby.

5.3 Superheat control with 2 temp. probes

The functional diagram is shown below. This type of control must be used with care, due to the lower precision of the temperature probe compared to the probe that measures the saturated evaporation pressure.

Parameter/ description Def.

Mode = Operating mode … 6 = Superheat control with 2 temperature probes

1 = Multiplexed showcase/ cold room

Par. Description Def. Min. Max. UoM

Superheat Superheat set point

CP ti

PID proport. gain 15 0 800 PID integral time 150 0 999 s

LowSH: threshold 55 (99) K(°F)

11(20)

Note: when selecting the type of Mode, the PID control values

suggested by CAREL will be automatically set for each application.

Control parameters for protection functions

See chapter on “Protectors”.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

EVD mini

Fig. 5.e

Key:

CP Compressor V Solenoid valve C Condenser S Liquid indicator L Liquid receiver EV Electronic valve F Dewatering ﬁlter E Evaporator T Temperature probe S1 Evaporation temperature probe S2 Suction temperature probe

For the wiring see chap. 2: “Description of the terminals”.

ENG

Par. Description Def Min Max UOM

Superheat Superheat set point 11(20) LowSH:

CP PID: proportional gain 15 0 800 ti PID: integral time 150 0 999 s

55(99) K

thresh.

5.4 Special functions

Hot gas bypass by pressure

This function can be used for cooling capacity control. If there is no request from circuit B, the compressor suction pressure decreases and the bypass valve opens, so as to deliver more hot gas and decrease circuit capacity.

M T

V1 V2

M T

EVD mini

Hot gas bypass by temperaturs

This function can be used for cooling capacity control. On a showcase, if the room temperature probe detects an increase in temperature, cooling capacity needs to increase, so the valve must close.

LEV

EVD mini

M T

V1 V2

Key

CP compressor V1 solenoid valve C condenser V2 thermostatic expansion valve L liquid receiver EV electronic valve F ﬁlter-drier E evaporator S liquid sightglass

For the wiring see the “General connection diagram”.

This is PID without any protection (LowSH, LOP, MOP, see the chapter on Protectors), no valve unblock procedure and no auxiliary control functions. The function uses the hot gas bypass temperature probe read by input S2, compared against the “Hot gas bypass temperature set point”. Control is reverse: as the temperature increases, the valve closes and vice-versa.

V1 V2

Key

CP compressor V1 solenoid valve C condenser V2 thermostatic expansion valve L liquid receiver EV electronic valve F ﬁlter-drier E evaporator S liquid sightglass

For the wiring see the “General connection diagram”.

This is PID without any protection (LowSH, LOP, MOP, see the chapter on Protectors), no valve unblock procedure and no auxiliary control functions. The function uses the hot gas bypass pressure probe read by input S1, compared against the “Hot gas bypass pressure set point”. Control is reverse: as the pressure increases, the valve closes and viceversa.

Par. Description Def Min Max UOM

_P Hot gas bypass pressure

set point CP PID: proportional gain 15 0 800 ti PID: integral time 150 0 999 s

3 -20(290) 200(2900) bar(psig)

Par. Description Def Min Max UOM

_t Hot gas bypass tempera-

ture set point CP PID: proportional gain 15 0 800 ti PID: integral time 150 0 999 s

10 -85(-121) 200(392) °C(°F)

5.5 Special control function: smooth lines

Note: the Smooth_line parameter is only accessible via the

supervisor.

The smooth lines function optimises evaporator capacity based on actual cooling demand, allowing more eﬀective and stable control. The function completely eliminates traditional on/oﬀ control cycles, modulating the temperature exclusively using the electronic valve; superheat set point is controlled through a precise PI control algorithm based on the actual control temperature. The master controller (connected via serial to EVD mini), through dynamic management of the Smooth_line parameter, modiﬁes the superheat set point for management of the electronic expansion valve, from a minimum (SH_SET) to a maximum (SH_SET + Smooth_line): this consequently acts directly on the PID control algorithm that modiﬁes the valve position. This is useful when the control temperature approaches the set point; the Smooth_line parameter is used to prevent the valve from closing, by reducing the evaporator’s cooling capacity. In order to use this function, the digital input must be conﬁgured as BACKUP. The Smooth_line parameter thus allows the control set point to be adjusted instantly. In the event where there is no network connection, the Smooth_line parameter is reset so as to resume normal control (START/STOP from digital input and SH_SET as the superheat set point).

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

The main eﬀects are:

• no swings in temperature and superheat due to the set point being

reached;

• stable temperature and superheat control;

• maximum energy savings due to load stabilisation.

Par. Description Def. Min. Max. UOM

Smooth_line

Key

SH set Superheat set point t time Temp.set Temperature set point

Note: the temperature setting based on the corresponding set point is managed by the master controller, while superheat control is managed by the EVD mini.

DI conﬁguration 1=start/stop - 2=control backup A: superheat set point oﬀset for smooth lines

SH_set+

Smooth_line

SH set

Temp. set

11 2 -

0 -99

(-55)99(55)

K/°F

5.6 Control parameters for protection

functions

See chapter on “Protectors”.

5.7 Service parameters

The other conﬁguration parameters, to be set where necessary before starting the controller, concern:

• the type of ratiometric pressure/temperature probe;

• the serial address for network connection;

• the type of unit of measure;

• enabling change in type of control (Mode);

• the number of steps (480/960) to control valve position.

Type of pressure/temperature probe (par. S1)

S1 is used to select the type of ratiometric pressure or NTC probe.

Par. Description Def. Min. Max. UOM

S1 Type of probe S1

1 = -1…4.2 barg

2 = 0.4…9.3 barg

3 = -1…9.3 barg

4 = 0…17.3 barg

5 = 0.85…34.2 barg

6 = 0…34.5 barg

7 = 0…45 barg

8 = -1…12.8 barg

9 = 0…20.7 barg

10 = 1.86…43.0 barg

11 = NTC (-50…105°C)

12 = Ratiometric (OUT=0-5V ) 0-60 barg

13 = Ratiometric (OUT=0-5V) 0-90 barg

14 = Remote pressure probe from RS485

3111-

Network address (par. n1)

See chap. “Network connection”

Unit of measure (par. Si)

The unit of measure used by the driver can be selected:

• S.I. (°C, K, barg);

• Imperial (°F, psig).

Par. Description Def. Min. Max. UOM

Si Unit of measure

1=°C/K/barg 2=°F/psig

Note: lthe unit of measure K or °F relates to degrees Kelvin or Fahrenheit adopted for measuring the superheat and the related parameters.

When changing the unit of measure, all the values of the parameters saved on the driver and all the measurements read by the probes will be recalculated. This means that when changing the units of measure, control remains unaltered.

Example 1: The pressure read is 20 barg, this will be immediately converted to the corresponding value of 290 psig.

Example 2: The “superheat set point” parameter set to 10 K will be immediately converted to the corresponding value of 18 °F.

112-

Access to Mode parameter (par. IA)

To avoid accidental modiﬁcation of the controller’s operating mode, it is possible to disable the access to the corresponding mode parameter (mode).

Par. Description Def. Min. Max. UOM

IA Enable operating mode modiﬁcation

0/1 = yes/ no

001-

Number of control steps (par. U3)

Total number of steps between the valve fully closed and fully open position

Par. Description Def. Min. Max. UOM

U3 Number of valve control steps

1 / 2 = 480/960 steps

112-

Digital input

The digital input function can be set by parameter:

Par. Description Def. Min. Max. UOM

di DI conﬁguration

1=Start/stop control; 2=Control backup

Start/Stop control:

• digital input closed: control activated;

• digital input open: driver in standby (see paragraph “Control status”);

Important: this setting excludes activation/deactivation of control from the network. See the next setting.

Control backup: when connected to a network, in the event of communication failures, the driver veriﬁes the status of the digital input to determine whether control is activated or in standby.

112-

Note: the maximum and minimum limits for the pressure probe

alarm can be set. See the parameter table.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

6. PROTECTORS

ENG

These are additional functions that are activated in speciﬁc situations that are potentially dangerous for the unit being controlled. They feature an integral action, that is, the action increases gradually when moving away from the activation threshold. They may add to or overlap (disabling) normal PID superheat control. By separating the management of these functions from PID control, the parameters can be set separately, allowing, for example, normal control that is less reactive yet much faster in responding when exceeding the activation limits of one of the protectors.

6.1 Protectors

The protectors are 3:

• LowSH, low superheat;

• LOP, low evaporation temperature;

• MOP, high evaporation temperature;

The protectors have the following main features:

• activation threshold: depending on the operating conditions of the

controlled unit, this is set in Service programming mode;

• integration time, which determines the intensity (if set to 0, the

protector is disabled): set automatically based on the type of main control;

• alarm, with activation threshold (the same as the protector) and

timeout (if set to 0 disables the alarm signal).

Note: The alarm signal is independent from the eﬀectiveness of the protector, and only signals that the corresponding threshold has been exceeded. If a protector is disabled (null integration time), the relative alarm signal is also disabled.

Each protector is inﬂuenced by the proportional gain parameter (CP) of PID superheat control. The higher is the value of CP, the more intensely the protection will react.

Characteristics of the protectors

Protection Reaction Reset

LowSH Intense closing Immediate LOP Intense opening Immediate MOP Moderate closing Controlled

Tab. 6.a

Reaction: summary description of the type of action in controlling the valve. Reset: summary description of the type of reset following the activation of the protector. Reset is controlled to avoid swings around the activation threshold or immediate reactivation of the protector.

Note: all the alarms are generated after a ﬁxed delay, as shown in the table:

The integration time is set automatically based on the type of main control.

Low_SH_TH

Low_SH

OFF

Fig. 6.a

key:

SH Superheat A Alarm Low_SH_TH Low_SH protection threshold D Alarm delay Low_SH Low_SH protection t Time B Alarm automatic reset

LOP (low evaporation pressure)

LOP= Low Operating Pressure

The LOP protection threshold is applied as a saturated evaporation temperature value so that it can be easily compared against the technical speciﬁcations supplied by the manufacturers of the compressors. The protector is activated so as to prevent too low evaporation temperatures from stopping the compressor due to the activation of the low pressure switch. The protector is very useful in units with compressors on board (especially multi-stage), where when starting or increasing capacity the evaporation temperature tends to drop suddenly. When the evaporation temperature falls below the low evaporation temperature threshold, the system enters LOP status and is the intensity with which the valve is opened is increased. The further the temperature falls below the threshold, the more intensely the valve will open. The integration time indicates the intensity of the action: the lower the value, the more intense the action.

Par. Description Def. Min. Max. U.M.

C3 LOP protection: threshold -50

C4 LOP protection: integration time 0 0 800 s

The integration time is set automatically based on the type of main control.

(-58)

-85 (-121)

MOP protec.: threshold

C(°F)

Protectors Delay (s)

LowSH 300 LOP 300 MOP 600

LowSH (low superheat)

The protector is activated so as to prevent the low superheat from causing the return of liquid to the compressor.

Par. Description Def. Min. Max. U.M.

C1 LowSH protection: threshold 5(9) -5(-9) Set point

superheat

C2 LowSH protection: integration time 15 0 800 s

When the superheat value falls below the threshold, the system enters low superheat status, and the intensity with which the valve is closed is increased: the more the superheat falls below the threshold, the more intensely the valve will close. The LowSH threshold must be less than or equal to the superheat set point. The low superheat integration time indicates the intensity of the action: the lower the value, the more intense the action.

K(°F)

Note:

• the LOP threshold must be lower then the rated evaporation

temperature of the unit, otherwise it would be activated unnecessarily, and greater than the calibration of the low pressure switch, otherwise it would be useless. As an initial approximation it can be set to a value exactly half-way between the two limits indicated;

• the protector has no purpose in multiplexed systems (showcases)

where the evaporation is kept constant and the status of the individual electronic valve does not aﬀect the pressure value;

• the LOP alarm can be used as an alarm to highlight refrigerant leaks by

the circuit. A refrigerant leak in fact causes an abnormal lowering of the evaporation temperature that is proportional, in terms of speed and extent, to the amount of refrigerant dispersed.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

T_EVAP

LOP_TH

LOP

ALARM

OFF

Fig. 6.b

Key:

T_EVAP Evaporation temperature D Alarm timeout LOP_TH Low evaporation temperature

protection LOP LOP protection t Time B Automatic alarm reset

ALARM Alarm

MOP (high evaporation pressure)

MOP= Maximum Operating Pressure.

The MOP protection threshold is applied as a saturated evaporation temperature value so that it can be easily compared against the technical speciﬁcations supplied by the manufacturers of the compressors. The protector is activated so as to prevent too high evaporation temperatures from causing an excessive workload for the compressor, with consequent overheating of the motor and possible activation of the thermal protector. The protector is very useful in self-contained units if starting with a high refrigerant charge or when there are sudden variations in the load. The protector is also useful in multiplexed systems (showcases), as allows all the utilities to be enabled at the same time without causing problems of high pressure for the compressors. To reduce the evaporation temperature, the output of the refrigeration unit needs to be decreased. This can be done by controlled closing of the electronic valve, implying superheat is no longer controlled, and an increase in the superheat temperature. The protector will thus have a moderate reaction that tends to limit the increase in the evaporation temperature, keeping it below the activation threshold while trying to stop the superheat from increasing as much as possible. Normal operating conditions will not resume based on the activation of the protector, but rather on the reduction in the refrigerant charge that caused the increase in temperature. The system will therefore remain in the best operating conditions (a little below the threshold) until the load conditions change.

T_EVAP

MOP_TH

MOP_TH - 1

MOP

PID

ALARM

OFF

Fig. 6.c

Key:

T_EVAP Evaporation temperature MOP_TH MOP threshold PID PID superheat control ALARM Alarm MOP MOP protection t Time D Alarm timeout

Important: the MOP threshold must be greater than the rated evaporation temperature of the unit, otherwise it would be activated unnecessarily. The MOP threshold is often supplied by the manufacturer of the compressor. It is usually between 10 °C and 15 °C.

If the closing of the valve also causes an excessive increase in the suction temperature (S2) above the set threshold – set via parameter (C7), not on the display - the valve will be stopped to prevent overheating the compressor windings, awaiting a reduction in the refrigerant charge. If the MOP protection function is disabled by setting the integral time to zero, the maximum suction temperature control is also deactivated.

Par. Description Def. Min. Max. U.M.

C7 MOP protection: disabling threshold

30 (86)

-85 (-121)

200 (392)

°C (°F)

At the end of the MOP protection function, superheat regulation restarts in a controlled manner to prevent the evaporation temperature from exceeding the threshold again.

Par. Description Def. Min. Max. U.M.

C5 MOP protection threshold 50

C6 MOP protection integration

time

Protection LOP:

(122)

threshold

20 0 800 s

200 (392)

C(°F)

The integration time is set automatically based on the type of main control.

When the evaporation temperature rises above the MOP threshold, the system enters MOP status, superheat control is interrupted to allow the pressure to be controlled, and the valve closes slowly, trying to limit the evaporation temperature. As the action is integral, it depends directly on the diﬀerence between the evaporation temperature and the activation threshold. The more the evaporation temperature increases with reference to the MOP threshold, the more intensely the valve will close. The integration time indicates the intensity of the action: the lower the value, the more intense the action.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

7. PARAMETERS TABLE

Par. Description Def. Min. Max. UOM Type Carel Modbus® R/W Note BASIC (INITIAL CONFIGURATION)

GAS

Refrigerant

Type

10 R717 24 HTR01 38 R452B 11 R744 (0...45 barg) 25 HTR02 39 R513A (-1...4.2 barg) 12 R728 26 R23 40 R454B 13 R1270 27 R1234yf 14 R417A 28 R1234ze

Mode Operating mode

Super

Superheat set point 11

Heat

_P Hot gas bypass pressure set point 3 -20(-

_t Hot gas bypass temperature set point 10 -85(-

SERVICE

P1 Probe S1 reading - -85

P2 Probe S2 reading - -85

tE Evaporation temperature (converted) - -85

tS Suction temperature - -85

Po Valve opening - 0 100 % A 1 0 R CP PID: proportional gain 15 0 800 - A 11 10 R/W ti PID: integral time 150 0 999 s I 17 144 R/W C1 LowSH protection: threshold 5(9) -5

C2 LowSH protection: integral time 15 0 800 s A 13 12 R/W C3 LOP protection: threshold -50(-58) -85(-

C4 LOP protection: integral time 0 0 800 s A 15 14 R/W C5 MOP protection: threshold 50

C6 MOP protection: integral time 20 0 800 s A 17 16 R/W C7 MOP protection: disabling threshold 30

C8 Low suction temperature alarm threshold -50

S1 Type of probe S1

Ratiometric (OUT=0…5V)

1 = -1…4.2 barg 8 = -1…12.8 barg 2 = 0.4…9.3 barg 9 = 0…20.7 barg 3 = -1…9.3 barg 10 = 1.86…43.0 barg 4 = 0…17.3 barg 11 = NTC (-50…105°C) 5 = 0.85…34.2 barg 12 = Ratiometric (OUT=0-5V) 0-60 barg 6 = 0…34.5 barg 13 = Ratiometric (OUT=0-5V) 0-90 barg 7 = 0…45 barg 14 = Remote pressure probe from RS485

n1 Network address 99 1 99 - I 10 137 R/W

(0...17.3 barg)

(-1...4.2 barg)

37 R508B (-1...4.2 barg)

41 R458A

3 1 41 - I 12 139 R/W

1 1 9 - I 13 140 R/W

LowSH

(20)

protection: threshold

290)

121)

(-290)

(-121)

(-9)

121)

(122)

LOP protection: threshold

-85

(86)

(-121)

(-58)

-85

(-121)

3 1 11 - I 14 141 R/W

(99)

200(2900) barg

200(392) °C(°F) A 22 21 R/W

200

(2900)

200

(392)

200

(392)

200

(392)

Superh. set

point

MOP

protection:

threshold

200

(392)

200

(392)

200

(392)

(°F)

(psig)

barg

(psig)

°C(°F)/VA7 6 R

°C

(°F)

°C

(°F)

°C

(°F)

°C

(°F)

°C

(°F)

°C

(°F)

A 10 9 R/W

A 23 22 R/W

A6 5 R

A4 3 R

A3 2 R

A 12 11 R/W

A 14 13 R/W

A 16 15 R/W

A 19 18 R/W

A 18 17 R/W

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

Par. Description Def. Min. Max. UOM Type Carel Modbus® R/W Note

n2 Baud rate (bit/s)

0 4800, 2 stop bit, parity none 9 4800, 1 stop bit, parity even 1 9600, 2 stop bit, parity none 10 9600, 1 stop bit, parity even 2 19200, 2 stop bit, parity none 11 19200, 1 stop bit, parity even 3 4800, 1 stop bit, parity none 12 4800, 2 stop bit, parity odd 4 9600, 1 stop bit, parity none 13 9600, 2 stop bit, parity odd 5 19200, 1 stop bit, parity none 14 19200, 2 stop bit, parity odd 6 4800, 2 stop bit, parity even 15 4800, 1 stop bit, parity odd 7 9600, 2 stop bit, parity even 16 9600, 1 stop bit, parity odd 8 19200, 2 stop bit, parity even 17 19200, 1 stop bit, parity odd

Si Unit of measure 1=°C/K/barg ¦ 2=°F/psig 1 1 2 - I 16 143 R/W IA Enable operating mode modiﬁcation 0/1 = yes/no 0 0 1 - I 15 142 R/W U1 Enable manual valve positioning 0/1 = no/yes 0 0 1 - D 11 10 R/W U2 Manual valve position 0 0 999 step I 7 134 R/W U3 Valve control steps: 1/2 = 480/960 steps 1 1 2 - I 11 138 R/W U4 Valve opening at start-up (evaporator/valve capacity ratio) 50 0 100 % I 19 146 R/W Fr Firmware version 1.3 - - - A 9 8 R di DI conﬁguration

1=start/stop control

2=control backup rt Reserved 1 1 1 L1 Pressure S1: MINIMUM alarm value -1 -85

H1 Pressure S1: MAXIMUM alarm value 9.3 Pressure

2 0 17 - I 20 147 R/W

1 1 2 - I 18 145 R/W

(-121)

S1: MIN

alarm value

Pressure S1: MAX

alarm value

200 (392) barg

barg

(psig)

A 20 19 R/W

A 21 20 R/W

Tab. 7.a

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

8. NETWORK CONNECTION

The driver can be connected via a network connection to:

1. a computer running the VPM software, for setting the parameters

before commissioning;

2. a pCO controller, loaded with the application program;

3. a PlantVisor/PlantVisorPRO supervisor, for remote monitoring and

alarm detection.

8.1 RS485 serial conﬁguration

n1 assigns to the controller an address for serial connection to a supervisory and/or telemaintenance system.

Par. Description Def. Min. Max. UoM

Network address 99 1 99 -

n2 Baud rate (bit/s)

0 4800, 2 stop bit, parity none 1 9600, 2 stop bit, parity none 2 19200, 2 stop bit, parity none 3 4800, 1 stop bit, parity none 4 9600, 1 stop bit, parity none 5 19200, 1 stop bit, parity none 6 4800, 2 stop bit, parity even 7 9600, 2 stop bit, parity even 8 19200, 2 stop bit, parity even 9 4800, 1 stop bit, parity even 10 9600, 1 stop bit, parity even 11 19200, 1 stop bit, parity even 12 4800, 2 stop bit, parity odd 13 9600, 2 stop bit, parity odd 14 19200, 2 stop bit, parity odd 15 4800, 1 stop bit, parity odd 16 9600, 1 stop bit, parity odd 17 19200, 1 stop bit, parity odd

Important: all controllers connected in a serial network need to be

set with the same communication parameters.

8.2 Network connection for commissioning via PC

Warnings:

• fasten the converter properly so as to prevent disconnection;

• complete the wiring without power connected;

• keep the CVSTDUMOR0 interface cables separate from the power

cables (power supply);

• in compliance with standards on electromagnetic compatibility, a

shielded cable suitable for RS485 data transmission is used.

The RS485 converter is used to connect a computer running the VPM software to the EVD mini driver via a serial network, for commissioning the controllers. The system allows a maximum of 99 units, with a maximum network length of 500 m. Connection requires the standard accessories (RS485-USB converter, CAREL P/N CVSTDUMOR0) and a 120 Ω terminating resistor to be installed on the terminals of the last connected controller. Connect the RS485 converter to controllers and make the connections as shown in the ﬁgure. To assign the serial address, see parameter n1. See the converter technical leaﬂets for further information.

2017-

ENG

USB

USB-485 Converter

GND

T -

T+

CVSTDUMOR0

shield

Fig. 8.a

8.3 Visual parameter manager

Go to http://ksa.carel.com and follow the instructions below. Select in sequence:

1. “Software & Support”

2. “Conﬁguration & Updating Softwares”

3. “Parametric Controller Software”

4. “Visual Parametric Manager”

A window will open with the possibility to download two ﬁles:

1. VPM_setup_X.Y.Z.W_full.zip: complete program;

2. X.Y.Z.W_VPM_Devices_Upgrade.zip: upgrade for supported devices;

If this is the ﬁrst installation, select Setup full, otherwise Upgrade. The program installs automatically by running setup.exe.

Note: if choosing complete installation (Setup full), uninstall any

previous versions of VPM.

Programming

When opening the program, the device to be conﬁgured needs to be selected: EVD mini. The Home page then opens, oﬀering the choice between starting a new project or opening an existing project. If using the program for the ﬁrst time, choose new project.

VPM

Tx/Rx Tx/ Rx + GND

EVD ice/mini

...n

Fig. 8.b

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

The following options are then available:

1. Directly access the list of parameters saved in EEPROM: select “RS485”;

The operations are performed in real time (ONLINE mode), at the top right set network address 99 and choose the guided procedure for USB port recognition, then go to “Device setup”;

Fig. 8.c

2. Select the model from the range based on the ﬁrmware version

and list of conﬁguration parameters (EVDMINI0000E0X_R*.*). These operations are performed in OFFLINE mode.

The pages marked 1) can be accessed wither Online or Oﬄine, while those marked 2) are Online only.

8.4 Restore default parameters

To restore the default parameter values on the controller:

1. Establish an RS485 serial connection between the computer and the

driver. The LEDs on the USB/RS485 converter will ﬂash;

Fig. 8.e

2. Select “Update device” and:

a. Click button (A) to open the drop-down menu; b. Select the list of parameters corresponding to the controller’s

ﬁrmware version: “EVDMINI***.hex”;

c. Click “Update” to load the parameters to the list and immediately

after restore the controller parameters to the default value.

Fig. 8.d

The operations that can be performed on the pages marked 1) depend on the ﬁrst selection made.

Note: to access the Online help press F1.

Ref. Description Home Select operating mode Online o RS485 (rear

Online Oﬄine

Device setup Read instant values of

control parameters

Setup summary Display the default values for the current list of

parameters

Prepare custom setup See online help. Update device Select list of parameters

and then Upload to controller

Upload ﬁrmware Select ﬁrmware and

Upload

Synoptic and graphs Overview with position

of probes and probe and superheat readings in real time

connector) Oﬄine o Device model

Select Load to load a list of project parameters (.hex), modify and save a new project.

Tab. 8.b

Fig. 8.f

3. Go to “Device setup”: the program automatically reads the default

parameters saved on the controller.

8.5 Setup by direct copy

1. On the Home page select RS485 (rear connector);

Fig. 8.g

2. Go to “Device setup”;

Fig. 8.h

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

a. on the “Rapid conﬁguration” page, set parameters “p_GAS_TYPE” =

refrigerant and “p_SUPER_MAIN_REGULATION”= type of control;

Fig. 8.i

b. on the “Conﬁguration” page, set parameter “p_SH_SET”.

Fig. 8.j

3. Check whether there are other parameters that need to be set (see

the “Functions” chapter);

4. Finally, select “Write” to copy the parameters to the controller.

Create the conguration le

1. Select the “Device setup” page;

2. Set the parameters by double clicking, as shown in the ﬁgure:

a. on the “Rapid conﬁguration” page, parameters “p_GAS_TYPE” =

refrigerant and “p_SUPER_MAIN_REGULATION”= type of control;

b. on the “Conﬁguration” page, parameter “p_SH_SET”.

Fig. 8.m

3. Save the list of parameters with a new name, for example “NEW_

NAME.hex”. To load and display a list saved by the user, select “Load” and navigate to the path where the ﬁle is saved. On the other hand, to load a list of parameters supplied by CAREL, select “Load” and navigate the following path:

LoadoPluginsoCommissioning EVD mini oTXToTXT32.

Fig. 8.k

8.6 Setup using conﬁguration ﬁle

On the Home page select “Device model”.

Fig. 8.l

The setup procedure comprises three steps:

1. Create the conﬁguration ﬁle;

2. Copy the conﬁguration ﬁle to the controller;

3. Read the conﬁguration ﬁle on the controller.

Save Load

Copy the conguration le to the controller

Select “Update device” and:

a. Click button (A) to open the drop-down menu;

NEW_NAME.hex

Fig. 8.n

b. Select the list of parameters corresponding to the project ﬁle created:

“NEW_NAME.hex”;

c. Click “Update” to UPLOAD the parameters to the controller.

8.7 Read the conﬁguration ﬁle on the controller

1. Go to the “Home” page and select RS485 (rear connector);

2. Go to “Device setup” to read the list of parameters on the controller

and make sure the settings are correct.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

8.8 Variables accessible via serial connection

Parameter Description Def. Min Max Type Carel Modbus® R/W Notes

Reg_status Controller status 0 0 20 I 1 128 R Machine_type_SPV Type of unit 0 0 32767 I 2 129 R Hardware_code_SPV Hardware code 0 0 32767 I 3 130 R EEV_Positions_steps Valve position 0 0 999 I 4 131 R Protection_status Protection status 0 0 5 I 5 132 R Sh_unit_power_percent Cooling capacity 0 0 100 I 6 133 R/W Man_posit_steps Manual valve position 0 0 999 I 7 134 R/W par. U2 Start_func_test Input variable in functional test 0 0 30000 I 8 135 R/W Func_test_2 Generic variable to use in the functional

test Net_address LAN serial network address 99 1 99 I 10 137 R/W par. n1 EEV_steps_doubling Double valve steps 1 1 2 I 11 138 R/W par. U3 Gas_type Refrigerant 3 1 23 I 12 139 R/W Gas Type = refrigerant Super_main_regulation Main control 1 0 9 I 13 140 R/W Mode = operating

Super_S1_probe_model Probe S1 3 1 14 I 14 141 R/W par. S1 Inhibit_mode_setting Enable mode parameter setting 0 0 1 I 15 142 R/W par. IA Unity_measure Unit of measure 1 1 2 I 16 143 R/W par. Si PID_Ti PID: integral time 150 0 999 I 17 144 R/W par. ti Par_Digin1_Conﬁg Digital input conﬁguration

1=Start/stop control

2=Control backup Start_eev_opening_ratio Valve position at start-up 50 0 100 I 19 146 R/W par. U4 Net setting Baud rate 2 0 17 I 20 147 R/W par. n2 Reset Default(*) Reset factory parameters 0 -32768 32767 I 21 148 R/W Ultracella signature Reserved 0 -32768 32767 I 22 149 R/W Regulation type Type of control 1 1 9 I 23 150 R Gas custom dew_a_h Dew point a high -288 -32768 32767 I 24 151 R/W Gas custom dew_a_l Dew point a low -15818 -32768 32767 I 25 152 R/W Gas custom dew_b_h Dew point b high -14829 -32768 32767 I 26 153 R/W Gas custom dew_b_l Dew point b low 16804 -32768 32767 I 27 154 R/W Gas custom dew_c_h Dew point c high -11664 -32768 32767 I 28 155 R/W Gas custom dew_c_l Dew point c low 16416 -32768 32767 I 29 156 R/W Gas custom dew_d_h Dew point d high -23322 -32768 32767 I 30 157 R/W Gas custom dew_d_l Dew point d low -16959 -32768 32767 I 31 158 R/W Gas custom dew_e_h Dew point e high -16378 -32768 32767 I 32 159 R/W Gas custom dew_e_l Dew point e low 15910 -32768 32767 I 33 160 R/W Gas custom dew_f_h Dew point f high -2927 -32768 32767 I 34 161 R/W Gas custom dew_f_l Dew point f low -17239 -32768 32767 I 35 162 R/W Net_alarm Network alarm 0 0 1 D 1 0 R al. E6 Emergency_closing_alarm No power supply 0 0 1 D 2 1 R al. E5 S1_alarm Probe S1 alarm 0 0 1 D 3 2 R al. A1 S2_alarm Probe S2 alarm 0 0 1 D 4 3 R al. A2 Low_sh_alarm Low_SH alarm 0 0 1 D 5 4 R al. E3 LOP_alarm LOP alarm 0 0 1 D 6 5 R al. E2 MOP_alarm MOP alarm 0 0 1 D 7 6 R al. E1 Low_suct_alarm Low suction temperature alarm 0 0 1 D 8 7 R al. E4 Eeprom_alarm EEPROM damaged 0 0 1 D 9 8 R al. EE Digin1_status Digital input status 0 0 1 D 10 9 R Manual_posit_enable Enable manual valve 0 0 1 D 11 10 R/W par. U1 Incomplete closing alarm Emergency closing not completed 0 0 1 D 12 11 R/W al. E8 Battery alarm Battery alarm 0 0 1 D 13 12 R EVD_CAN_GO Enable EVD control 0 0 1 D 14 13 R/W S1_Alarm_enable Enable probe S1 0 0 1 D 15 14 R/W S2_Alarm_enable Enable probe S2 0 0 1 D 16 15 R/W EEV_Position_percent Valve opening 0 0 100 A 1 0 R par. Po SH_SH Superheat 0 -5

Sh_Suct_temp Suction temperature 0 -85(-121) 200(392) A 3 2 R par. tS Sh_Evap_temp Evaporation temperature 0 -85(-121) 200(392) A 4 3 R Sh_Evap_pres Evaporation pressure 0 -20(-290) 200(2900) A 5 4 R S1_Value Probe S1 reading 0 -85(-290) 200(2900) A 6 5 R par. P1 S2_Value Probe S2 reading 0 -85(-121) 200(392) A 7 6 R par. P2 Positioning_mode_volt 0-10 V input 0 0 10 A 8 7 R Firm_release Firmware version 0 0 800 A 9 8 R par. Fr SH_Set Superheat set point 11 Low_

PID_Kp PID: proportional gain 15 0 800 A 11 10 R/W par. CP Low_sh_threshold Low superheat: threshold 5 -5(-9) Set point

Low_sh_Ti Low superheat: integral time 15 0 800 A 13 12 R/W par. C2 Lop_threshold LOP: threshold -50(-58) -85(-121) MOP_th-

Lop_Ti LOP: integral time 0 0 800 A 15 14 R/W par. C4 MOP_Threshold MOP: threshold 50 LOP_th-

MOP_Ti MOP: integral time 20 0 800 A 17 16 R/W par. C6 Low_Suct_alarm_threshold Low suction temperature alarm threshold -50(-58) -85(-121) 200(392) A 18 17 R/W par. C8 Mop_Inhibition_threshold MOP: inhibition threshold 30 (86) -85

0 -32768 32767 I 9 136 R/W

1 1 2 I 18 145 R/W

(-9)

Sh_Threshold

reshold

(-121)

55 (99)

55(99) A 10 9 R/W Super heat = superheat

surrisc.

reshold

200 (392)

A2 1 R

A 12 11 R/W par. C1

A 14 13 R/W par. C3

A 16 15 R/W par. C5

A 19 18 R/W

mode

set point

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

Parameter Description Def. Min Max Type Carel Modbus® R/W Notes

S1_Alarm_threshold_ low

S1_Alarm_threshold_ high

TCTRL_REV_SET Hot gas bypass temperature set point 10 -85

PCTRL_REV_SET Hot gas bypass pressure set point 3 -20

SH_actual_set Reserved SH_Set_smooth_line Superheat set point oﬀset for smooth

S1_value_remote S1 probe reading from supervisor (*) set to 1973 to reset the parameters to the default values

Pressure S1: MINIMUM alarm value -1 -85(-290) Par_S1_

Pressure S1: MAXIMUM alarm value 9.3 Par_

0 0

lines

S1_Ala rm_threshold _ low

(-121)

(-290)

-40(-72)

-55(-99)

-20(-290)

Alarm_threshold _ high 200(2900) A 21 20 R/W

200 (392) 200 (2900)

180(324) A 24 23 R 55(99) A 25 24 R/W

200(2900) A 26 25 R/W

A 20 19 R/W

A 22 21 R/W par. _t

A 23 22 R/W par. _P

ENG

Tab. 8.c

8.9 Control states

The electronic valve controller can have six diﬀerent control states, each of which may correspond to a speciﬁc phase in the operation of the refrigeration unit and a certain status of the driver-valve system. The states are as follows:

• forced closing: initialisation of the valve position when switching the

instrument on;

• standby: no temperature control, unit OFF (at temp.);

• wait: opening of the valve before starting control, also called pre-

positioning, when powering the unit on;

• control: eﬀective control of the electronic valve, unit ON;

• positioning: step-change in the valve position, corresponding to the

start of control when the cooling capacity of the controlled unit varies (only EVD connected to a pCO);

• stop: of control with closing of the valve, corresponds to the end of

temperature control of the refrigeration unit, unit OFF (at temp.).

Forced closing

Forced closing is performed after the driver is powered on and corresponds to the typical number of closing steps for CAREL E2V and E3V unipolar valves. This is used to realign the valve to the physical position corresponding to completely closed. The driver and the valve are then ready for control and both aligned at 0 (zero). At power-on, ﬁrst a forced closing is performed, and then the standby phase starts. The valve is also closed in the event of a mains power failure if the Ultracap module is connected. In this case, the “Forced valve closing not completed” parameter is set to 1. On restarting, if the valve forced closing procedure is not completed successfully:

1. the Master programmable controller (pCO) will check the value of

the parameter, and if equal to 1 will decide the best strategy to adopt, based on the application;

2. on restarting the driver positions the valve as explained in the

paragraph “Pre-positioning/start control”. The parameter is set to 0 (zero) by the Master controller (e.g. pCO), or alternatively by pressing the PRG/Set button on the keypad. Once the parameter has been set to 1, the driver sets it back to 0 (zero) only if an emergency forced closing procedure is completed successfully.

Note: lthe user can only select the resolution of the valve control

signal: 480 or 960 steps.

Par. Description Def. Min. Max. UoM

U3 Valve control steps

1 / 2 = 480/ 960 steps

Standby

Standby corresponds to a situation of rest in which no signals are received to control the electronic valve: it is closed and manual positioning can be activated. This status is normally set on the driver when the refrigeration unit is shutdown manually (e.g. from the supervisor) or when reaching the control set point. It can also occur when opening the digital input (which involves closing the valve) or in the event of a probe alarm. In general, it can be said that the electronic valve driver is in standby when the compressor stops or the control solenoid valve closes.

12-

Pre-positioning/start control

If during standby a control request is received, before starting control the valve is moved to a precise initial position. Internally, the pre-positioning time is set at 6 s and represents the time that the valve is held in a ﬁxed position. By default the valve is opened 50 % when starting (from digital input), so as to minimise the movement needed to reach the correct position.

Par. Description Def. Min. Max. UoM

U4 Valve opening at start-up 50

This parameter should be set based on the ratio between the rated cooling capacity of the evaporator and the valve (e.g. rated evaporator cooling capacity: 3kW, rated valve cooling capacity: 10kW, valve opening = 3/10 = 33%).

The driver calculates the valve opening based on the required capacity:

If required capacity is 100%:

Opening (%)= (Valve opening at start-up);

If required capacity is less than 100% (capacity control):

Opening (%)= (Valve opening at start-up) x (Current unit cooling capacity), where the current unit cooling capacity is sent to the driver via RS485 by the pCO controller. If the driver is stand-alone, this is always equal to 100%.

Notes:

0 100 %

• this procedure is used to anticipate the movement and bring the valve

signiﬁcantly closer to the operating position in the phases immediately after the unit is powered on;

• if there are problems with liquid return after the refrigeration unit starts

or in units that frequently switch on-oﬀ, the valve opening at start-up must be decreased. If there are problems with low pressure after the refrigeration unit starts, the valve opening must be increased.

Wait

When the calculated position has been reached, regardless of the time taken (this varies according to the type of valve and the objective position), there is a constant 5 second delay before the actual control phase starts. This is to create a reasonable interval between standby, in which the variables have no meaning, as there is no ﬂow of refrigerant, and the eﬀective control phase.

Control

The control request can be received by the closing of the digital input or via network (RS485). The solenoid or the compressor are activated when the valve, following the pre-positioning procedure, has reached the calculated position. The following ﬁgure represents the sequence of events for starting control of the refrigeration unit.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

OFF

T1 W

Fig. 8.o

Key:

A Control request T1 Pre-positioning time P Pre-positioning W Wait (wait) S Standby t Time R Control

Positioning (change cooling capacity)

This control status is only valid for controllers connected to the pCO via RS485. If there is a change in unit cooling capacity of at least 10%, sent from the pCO via RS485, the valve is positioned proportionally. In practice, this involves repositioning starting from the current position in proportion to how much the cooling capacity of the unit has increased or decreased in percentage terms. When the calculated position has been reached, regardless of the time taken, there is a constant 5 second delay before the actual control phase starts.

Note: if information is not available on the variation in unit cooling capacity, this will always be considered as operating at 100% and therefore the procedure will never be used. In this case, the PID control must be more reactive (see the chapter on Control) so as to react promptly to variations in load that are not communicated to the driver.

OFF

T3 W

OFF

Fig. 8.q

Key:

Control request R Control

Standby T4 Stop position time

Stop t Time

8.10 Special control states

As well as normal control status, the driver can have three special states related to speciﬁc functions:

• manual positioning: this is used to interrupt control so as to move the

valve, setting the desired position;

• recover physical valve position: recover physical valve steps when fully

opened or closed;

• unblock valve: forced valve movement if the driver considers it to be

blocked.

Manual positioning

Manual positioning can be activated at any time during the standby or control phase. Manual positioning, once enabled, is used to freely set the position of the valve using the corresponding parameter.

Control is placed on hold, all the system and control alarms are enabled, however neither control nor the protectors can be activated. Manual positioning thus has priority over any driver state/protector.

Par. Description Def. Min. Max. UoM

U1 Enable manual valve positioning:

0/1=yes/no

U2 Manual valve position 0

Notes:

1. the manual positioning status is NOT saved when restarting after a

power failure.

2. in for any reason the valve needs to be kept stationary after a power

failure, proceed as follows:

• remove the valve stator;

• set the PID proportional gain =0. The valve will remain stopped at

the initial opening position, set by corresponding parameter

01-

0 999

step

Fig. 8.p

Key:

Control request R Control

Change in capacity T3 Repositioning time

Repositioning t Time

Wait

Stop/end control

The stop procedure involves closing the valve from the current position until reaching 0 steps, plus a further number of steps so as to guarantee complete closing. Following the stop phase, the valve returns to standby.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

Retrieve physical valve position

This procedure is necessary as the stepper motor intrinsically tends to lose steps during movement. Given that the control phase may last continuously for several hours, it is probable that from a certain time on the estimated position sent by the valve driver does not correspond exactly to the physical position of the movable element. This means that when the driver reaches the estimated fully closed or fully open position, the valve may physically not be in that position. The “Synchronisation” procedure allows the driver to perform a certain number of steps in the suitable direction to realign the valve.

Note: realignment is in intrinsic part of the forced closing procedure and is activated whenever the driver is stopped/started and in the standby phase.

Unblock valve

This procedure is only valid when the driver is performing superheat control. Unblock valve is an automatic safety procedure that attempts to unblock a valve that is supposedly blocked based on the control variables (superheat, valve position). The unblock procedure may or may not succeed depending on the extent of the mechanical problem with the valve. If for 10 minutes the conditions are such as to assume the valve is blocked, the procedure is run a maximum of 5 times. The symptoms of a blocked valve do not necessarily mean a mechanical blockage. They may also represent other situations:

• mechanical blockage of the solenoid valve upstream of the electronic

valve (if installed);

• electrical damage to the solenoid valve upstream of the electronic

valve;

• blockage of the ﬁlter upstream of the electronic valve (if installed);

• electrical problems with the electronic valve motor;

• electrical problems in the driver-valve connection cables;

• incorrect driver-valve electrical connection;

• electronic problems with the valve control driver;

• secondary ﬂuid evaporator fan/pump malfunction;

• insuﬃcient refrigerant in the refrigerant circuit;

• refrigerant leaks;

• lack of subcooling in the condenser;

• electrical/mechanical problems with the compressor;

• processing residues or moisture in the refrigerant circuit.

ENG

Note: the valve unblock procedure is nonetheless performed in each of these cases, given that it does not cause mechanical or control problems. Therefore, also check these possible causes before replacing the valve.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

9. ALARMS

9.1 Types of alarms

There are two types of alarms:

• system: EEPROM, probe and communication;

• control: low superheat, LOP, MOP, low suction temperature.

The activation of the alarms depends on the setting of the threshold and activation delay parameters. The EEPROM unit parameters and operating parameters alarm always shuts down the controller and cannot be reset. All the alarms are reset automatically, once the causes are no longer present, except for the “Emergency closing not completed” alarm, which requires manual reset.

Example 1: the board without display has the red alarm is active. For EEPROM alarms, it stays on steady.

ﬂashing when an

Fig. 9.a

9.2 Probe alarms

The probe alarms are part of the system alarms. When the value measured by one of the probes is outside of the range of measurement, an alarm is activated. The alarm limits correspond to the range of measurement.

In the event of a probe alarm, the driver closes the valve, regardless of digital input status, until the error is no longer present.

Example: the display shows probe alarms A1 and A2 in sequence. The superheat value has exceeded the maximum limit allowed, and this is indicated by the two top segments.

GAS Type

Mode

Super Heat

GAS Type

Mode

Super Heat

Fig. 9.b

Minimum and maximum superheat limits

If a probe alarm occurs, it may be due to the superheat value exceeding the allowed display range -5…55 K (-9 to 99°F). The display therefore shows the probe alarm code (A1/A2) and:

1. if the superheat value is less than -5K, the display shows the two

bottom segments;

2. if the superheat value is higher than 55K, the display shows the two

top segments.

GAS Type

Mode

Super Heat

9.3 Control alarms

These are alarms that are only activated during control.

Protector alarms

The alarms corresponding to the LowSH, LOP and MOP protectors are only activated during control when the corresponding activation threshold is exceeded, and only when the delay time deﬁned by the corresponding parameter has elapsed. If a protector is not enabled (integral time= 0 s), no alarm will be signalled. If before the expiry of the delay, the protector control variable returns back inside the corresponding threshold, no alarm will be signalled.

Note: this is a likely event, as during the delay, the protection

function will have an eﬀect.

Low suction temperature alarm

The low suction temperature alarm is not linked to any protection function. It features a threshold and a ﬁxed delay (300 seconds), and is useful in the event of probe or valve malfunctions to protect the compressor using the relay to control the solenoid valve or to simply signal a possible risk. In fact, incorrect measurement of the evaporation pressure or incorrect conﬁguration of the type of refrigerant may mean the superheat calculated is much higher than the actual value, causing an incorrect and excessive opening of the valve. A low suction temperature measurement may in this case indicate probable ﬂooding of the compressor, with corresponding alarm signal. The alarm is reset automatically, with a ﬁxed diﬀerential of 3°C above the activation threshold.

Par. Description Def. Min. Max. UoM

C8 Low suction temperature

alarm threshold

-50 (-58)

-85 (-121)

200 (392)

°C(°F)

9.4 Valve emergency closing procedure

The following description only applies if EVD mini is connected to the Ultracap module.

In the event of a power failure, EVD mini can provide emergency closing of the valve, thus preventing any refrigerant from ﬂowing to the compressor.

In this situation, the driver generates two alarms: E8 and E5. If the procedure concludes successfully (the valve closes completely), alarm E8 is cleared, however alarm E5 continues until the Ultracap module is able to power on the driver.

• E8: failed emergency closing (incomplete closing alarm). Active

during the emergency closing stage and until the valve closes completely, after which alarm E8 is cleared. If the closing procedure is not completed (e.g. because the Ultracap module does not have enough charge), when next restarting the controller, the user must manually reset the alarm (pressing the PRG/SET button or setting the corresponding parameter to zero via serial connection);

• E5: emergency closing (emergency force closing alarm). This depends

on a controller power failure and indicates that the emergency procedure is in progress.

GAS Type

Mode

Super Heat

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

Mode

Fig. 9.c

GAS Type

Super Heat

Notes:

• if the voltage measured falls below a certain threshold, the controller,

connected to the Ultracap module, can start the valve emergency closing procedure;

• during the valve emergency closing procedure, the display is switched

oﬀ to save energy (therefore the alarms may not be shown on the display, or only shown for a brief instant);

• if power returns during the closing procedure, alarms E8 and E5 are

reset and closing is completed in any case.

9.5 Network alarm

The digital input conﬁguration parameter can only be set to control backup from the supervisor. If there is a communication error between the pCO controller and driver, the digital input status determines whether to continue control (input closed = the valve remains in the current position) or stop (input open).

9.6 Alarm table

ENG

Alarm code on the display

A1 ﬂashes Probe S1 faulty or set alarm range

A2 ﬂashes Probe S2 faulty or set alarm range

E1 ﬂashes MOP protection activated automatic Protection action already

E2 ﬂashes LOP protection activated automatic Protection action already

E3 ﬂashes LowSH protection activated automatic Protection action already

E4 ﬂashes Low suction temperature automatic No eﬀect Check the threshold parameter. E5 ﬂashes Chiusura di emergenza: LowSH,

E6 ﬂashes Network error automatic Control based on DI Check the wiring and that the pCO is

E7 ﬂashes Ultracap module powered at low volta-

E8 ﬂashes Emergency closing not completed Manual Valve closed Press PRG/Set or set the corresponding

EE on steady EEPROM operating and/or unit parame-

Red LED Cause of the alarm Reset Eﬀects on control Checks / Solutions

exceeded

LOP, MOP, bassa T/P di aspirazione, mancanza di alimentazione

ge or low charge

ters damaged

automatic Valve closed Check the probe connections.

in progress

automatic Valve closed Reset power supply

automatic No eﬀect Check the wiring, the power supply

Replace the driver/ Contact service

Total shutdown Replace the driver/Contact service

Check parameter “MOP protection: threshold” Check parameter “LOP protection: threshold” Check parameter “LowSH protection: threshold”

on and operating

and that the minimum recharge time has elapsed

supervisor variable to 0

Tab. 9.d

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ENG

10. TROUBLESHOOTING

The following table lists a series of possible malfunctions that may occur when starting and operating the driver and the electronic valve. These cover the most common problems and are provided with the aim of oﬀering an initial response for resolving the problem.

PROBLEM CAUSE SOLUTION

The superheat value measured is incorrect

Liquid returns to the compressor during control

Liquid returns to the compressor only after defrosting (for multiplexed cabinets only)

Liquid returns to the compressor only when starting the controller (after being OFF)

The superheat value swings around the set point with an amplitude greater than 4°C

In the start-up phase with high evaporator temperatures, the evaporation pressure is high

The probe does not measure correct values Check that the pressure and the temperature measured are correct and that the probe

The type of refrigerant set is incorrect Check and correct the type of refrigerant parameter. The superheat set point is too low Increase the superheat set point. Initially set it to 11 K and check that there is no longer

Low superheat protection ineﬀective If the superheat remains low for too long with the valve that is slow to close, increase

Stator broken or connected incorrectly Disconnect the stator from the valve and the cable and measure the resistance of the

Valve stuck open Check if the superheating is always low (<2 °C) with the valve position permanently at

The “valve opening at start-up” parameter is too high on many cabinets in which the control set point is often reached (for multiplexed cabinets only) The superheat temperature measured by the driver after defrosting and before reaching operating conditions is very low for a few minutes The superheat temperature measured by the driver does not reach low values, but there is still return of liquid to the compressor rack Many cabinets defrosting at the same time Stagger the start defrost times. If this is not possible, if the conditions in the previous

The valve is signiﬁcantly oversized Replace the valve with a smaller equivalent. The “valve opening at start-up” parameter is set too high

The condensing pressure swings Check the controller condenser settings, giving the parameters “blander” values (e.g.

The superheat swings even with the valve set in manual control (in the position corresponding to the average of the working values) The superheat does NOT swing with the valve set in manual control (in the position corresponding to the average of the working values) The superheat set point is too low Increase the superheat set point and check that the swings are reduced or disappear.

MOP protection disabled or ineﬀective Activate the MOP protection by setting the threshold to the required saturated eva-

Refrigerant charge excessive for the system or extreme transitory conditions at start-up (for cabinets only).

position is correct. correct probe electrical connections.

return of liquid. Then gradually reduce the set point, always making sure there is no return of liquid.

the low superheat threshold and/or decrease the low superheat integration time. Initially set the threshold 3 °C below the superheat set point, with an integration time of 3-4 seconds. Then gradually lower the low superheat threshold and increase the low superheat integration time, checking that there is no return of liquid in any operating conditions.

windings using an ordinary tester. The resistance of both should be around 40 ohms. Otherwise replace the stator.

0 steps. If so, set the valve to manual control and close it completely. If the superheat is always low, check the electrical connections and/or replace the valve.

Decrease the value of the “Valve opening at start-up” parameter on all the utilities, making sure that there are no repercussions on the control temperature.

Check that the LowSH threshold is greater than the superheat value measured and that the corresponding protection is activated (integration time >0 s). If necessary, decrease the value of the integration time.

Set more reactive parameters to bring forward the closing of the valve: increase the proportional factor to 30, increase the integration time to 250 s.

two points are not present, increase the superheat set point and the LowSH thresholds by at least 2 °C on the cabinets involved.

Check the calculation in reference to the ratio between the rated cooling capacity of the evaporator and the capacity of the valve; if necessary, lower the value.

increase the proportional band or increase the integration time). Note: the required stability involves a variation within +/- 0.5 bars. If this is not eﬀective or the settings cannot be changed, adopt electronic valve control parameters for perturbed systems Check for the causes of the swings (e.g. low refrigerant charge) and resolve where possible.

As a ﬁrst approach , decrease (by 30 to 50 %) the proportional factor. Subsequently try increasing the integration time by the same percentage. In any case, adopt parameter settings recommended for stable systems.

Initially set 13 °C, then gradually reduce the set point, making sure the system does not start swinging again and that the unit temperature reaches the control set point.

poration temperature (high evaporation temperature limit for the compressors) and setting the MOP integration time to a value above 0 (recommended 4 seconds). To make the protection more reactive, decrease the MOP integration time. Apply a “soft start” technique, activating the utilities one at a time or in small groups. If this is not possible, decrease the values of the MOP thresholds on all the utilities.

Make sure the correct pressure probe has been set. Check the

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

PROBLEM CAUSE SOLUTION

In the start-up phase the low pressure protection is activated (only for selfcontained units)

The unit switches oﬀ due to low pressure during control (only for self-contained units)

The “Valve opening at start-up” parameter is set too low The driver in RS485 network does not start control and the valve remains closed

The driver in stand-alone conﬁguration does not start control and the valve remains closed LOP protection disabled Set a LOP integration time greater than 0 s. LOP protection ineﬀective Make sure that the LOP protection threshold is at the required saturated evaporation

Solenoid blocked Check that the solenoid opens correctly, check the electrical connections. Insuﬃcient refrigerant Check that there are no bubbles in the sight glass upstream of the expansion valve.

The valve is connected incorrectly (rotates in reverse) and is open

Stator broken or connected incorrectly Disconnect the stator from the valve and the cable and measure the resistance of the

Valve stuck closed Use manual control after start-up to completely open the valve. If the superheat

LOP protection disabled Set a LOP integration time greater than 0 s. LOP protection ineﬀective Make sure that the LOP protection threshold is at the required saturated evaporation

Solenoid blocked Check that the solenoid opens correctly, check the electrical connections and the

Insuﬃcient refrigerant Check that there are no bubbles of air in the liquid indicator upstream of the expansion

The valve is signiﬁcantly undersized Replace the valve with a larger equivalent. Stator broken or connected incorrectly Disconnect the stator from the valve and the cable and measure the resistance of the

Valve stuck closed Use manual control after start-up to completely open the valve. If the superheat

Check the calculation in reference to the ratio between the rated cooling capacity of the evaporator and the capacity of the valve; if necessary lower the value. Check the serial connection. Check that the pCO application connected to the driver (where featured) correctly manages the driver start signal. Check that the driver is NOT in stand-alone mode. Check the connection of the digital input. Check that when the control signal is sent that the input is closed correctly. Check that the driver is in stand-alone mode.

temperature (between the rated evaporation temperature of the unit and the corresponding temperature at the calibration of the low pressure switch) and decrease the value of the LOP integration time.

Check that the subcooling is suitable (greater than 5 °C); otherwise charge the circuit.

Check the movement of the valve by placing it in manual control and closing or opening it completely. One complete opening must bring a decrease in the superheat and vice-versa. If the movement is reversed, check the electrical connections.

windings using an ordinary tester. The resistance of both should be around 40 ohms. Otherwise replace the stator.

remains high, check the electrical connections and/or replace the valve.

temperature (between the rated evaporation temperature of the unit and the corresponding temperature at the calibration of the low pressure switch) and decrease the value of the LOP integration time.

operation of the control relay.

valve. Check that the subcooling is suitable (greater than 5 °C); otherwise charge the circuit.

windings using an ordinary tester. The resistance of both should be around 40 ohms. Otherwise replace the stator.

remains high, replace the valve body.

ENG

The cabinet does not reach the set temperature, despite the value being opened to the maximum (for multiplexed cabinets only)

The cabinet does not reach the set temperature, and the position of the valve is always 0 (for multiplexed cabinets only)

Solenoid blocked Check that the solenoid opens correctly, check the electrical connections and the

Insuﬃcient refrigerant Check that there are no bubbles of air in the liquid indicator upstream of the expansion

Valve stuck closed Use manual control after start-up to completely open the valve. If the superheat

The driver in RS485 network does not start control and the valve remains closed

The driver in stand-alone conﬁguration does not start control and the valve remains closed

operation of the relay.

valve. Check that the subcooling is suitable (greater than 5 °C); otherwise charge the circuit.

windings using an ordinary tester. The resistance of both should be around 40 Ω. Otherwise replace the stator.

remains high, replace the valve body.

Check the network connections. Check that the pCO application connected to the driver (where featured) correctly manages the driver start signal. Check that the driver is NOT in stand-alone mode.

Check the connection of the digital input. Check that when the control signal is sent that the input is closed correctly. Check that the driver is in stand-alone mode.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

ENG

11. TECHNICAL SPECIFICATIONS

EVD mini (24 V) EVD mini (230 V)

Power supply

1. 24 Vac (+10/-15%) 50/60 Hz.

• Use a class II isolating transformer (min 20VA, max 50VA)

• Length of connection between transformer and EVDmini

Lmax=1 m

2. 24 Vdc (+10/-15%)

• Use an external 24 Vdc power supply, min 15 W

Max power consumption (W) 13 15 Emergency power supply 13 Vdc +/-10% (If the optional Ultracap module for EVD mini is installed) Driver Unipolar valve

Connections: Motor connection 6-wire cable type AWG 18/22, Lmax=1m (see NOTE)

Digital inputs connection Digital input to be activated from voltage-free contact or

Probes Lmax=10 m for residential/industrial, 2 m for domestic environments

Power to active probes (V REF) +5Vdc+/-2% RS485 serial connection Modbus, Lmax=500 m, shielded cable, earth both ends of the cable shield Assembly on DIN rail or with screws on DIN rail

Connectors wire size 0,35...2,5 mm Dimensions Base x height x depth = 88 x 90 x 33 mm Base x height x depth = 70,4 x 114 x 38 mm Operating conditions -25T60°C; <90% U.R. non-condensing Storage conditions -35T60°C, <90% U.R. non-condensing Index protection IP00 Environmental pollution 2 Resistance to heat and ﬁre Category D Overvoltage category Category II Insulation class III II Class and software structure A

Conformity Electrical safety EN 60730-1, UL 60730-1, UL 60730-2-9 Electromagnetic compatibility EN 61000-6-1, EN 61000-6-2, EN 61000-6-3, EN 61000-6-4

transistor to GND. Closing current: 5mA. Maximum contact resistance: <50Ω Lmax=10 m for residential/industrial, 2 m for domestic environments

Low temperature NTC:

Ratiometric pressure probe (0…5V)

Low temperature NTC:

Input 0…10V (max 12V)

10 kΩ a 25°C, -50T90°C Measurement error: 1°C in the range -50T50°C; 3°C in the range +50T90°C Resolution 0,1 % fs Measurement error: 2% fs maximum; 1% typical

10kΩ a 25°C, -50T90°C Measurement error: 1°C in the range -50T50°C; 3°C in the range +50T90°C Resolution 0,1 % fs Measurement error: 9% fs maximum; 8% typical

EN61000-3-2, EN55014-1, EN61000-3-3

115…230 Vac (+10/-15%) 50/60 Hz

• Length of power supply cable: Lmax=1 m.

Digital input 230 Vac optoisolated Closing current: 10 mA

(12...22 AWG)

Note: if using in domestic and/or residential environments (EN55014-1/EN61000-6-3) with the controller not installed inside a metallic panel, ﬁt the ferrite (P/N 0907879AXX

• for EVD mini 24 V: applied on the valve stator cable if using in domestic/

residential environments with valve cable > 0.5 m;

• for EVD mini 115/ 230 V: applied on the valve stator cable if using in

domestic/residential environments with valve cable > 0-4 m.

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

CAREL I NDUSTRIES HeadQuarters

Via dell’Industria, 11 - 35020 Brugine - Padova (Italy) Tel. (+39) 049.9716611 - Fax (+39) 049.9716600 e-mail: carel@carel.com - www.carel.com

Agenzia / Agency:

“EVD mini” +0300036EN - rel. 1.2 - 23.04.2018

Carel EVD mini User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual