dixell XEV11D Operating Instructions Manual

dIXEL

Operating instruction manual

1592019010

1592019010 XEV11D GB r1.2 2008.07.08.doc XEV11D 1/4

XEV11D

ON-OFF ELECTRONIC EXPANSION VALVE DRIVERS

CONTENTS

1.

General warning _____________________________________________________1

2. General description ___________________________________________________1

3. Regulation __________________________________________________________1

4. Front panel _________________________________________________________ 1

5. User interface _______________________________________________________2

6. Parameters list ______________________________________________________ 2

7. Digital inputs ________________________________________________________ 3

8. Plant starting function _________________________________________________ 3

9. Electrical connections _________________________________________________3

10. RS485 serial line _____________________________________________________3

11. How to use the HOT KEY ______________________________________________ 3

12. Display messages ____________________________________________________3

13. Technical data_______________________________________________________3

14. Wiring connections ___________________________________________________ 3

15. Standard values _____________________________________________________ 3

16. Example of application ________________________________________________ 4

1. GENERAL WARNING

1.1 PLEASE READ BEFORE USING THIS MANUAL

• This manual is part of the product and should be kept near the instrument for easy and quick
reference.

• The instrument shall not be used for purposes different from those described hereunder. It
cannot be used as a safety device.

• Check the application limits before proceeding.

1.2 SAFETY PRECAUTIONS

• Check the supply voltage is correct before connecting the instrument.

• Do not expose to water or moisture: use the controller only within the operating limits avoiding

sudden temperature changes with high atmospheric humidity to prevent formation of
condensation

• Warning: disconnect all electrical connections before any kind of maintenance.

• Fit the probe where it is not accessible by the End User. The instrument must not be opened.

• In case of failure or faulty operation send the instrument back to the distributor or to “Dixell

S.p.A.” (see address) with a detailed description of the fault.

• Consider the maximum current which can be applied to each relay (see Technical Data).

• Ensure that the wires for probes, loads and the power supply are separated and far enough from

each other, without crossing or intertwining.

• In case of applications in industrial environments, the use of mains filters (our mod. FT1) in
parallel with inductive loads could be useful.

2. GENERAL DESCRIPTION

The XEV11D module is able to drive ON/OFF electronic expansion valves. This module permits to
regulate the superheat (SH) of the fluid that runs into refrigerating unit in order to obtain optimized
performance and a climatic or load conditions independent functioning. XEV11D modules are
equipped with two probe inputs, one for 4÷20mA or 0÷5V pressure transducer and another for Pt1000
or NTC temperature probe. A LAN connection permits to transmit the pressure signal to all other XEV
modules in order to use only one pressure transducer in multiplexed cabinet applications. There are
also two configurable digital inputs, one of them must be configured to get cooling request. The other
digital input can be used to signal to the instrument that defrost is in progress. To complete instrument
equipment, a RS485 serial link permits to connect XEV11D to dIXEL monitoring and supervising
systems.

XEV11D can be programmed with KB1-PRG remote keyboard or with Dixell HOT-KEY.

3. REGULATION

The superheat regulation is performed only when the cooling request is active. The following scheme
shows how device reads the request of cooling:

The regulation is obtained with PI controller that it changes the valve opening percentage. Opening
percentage is obtained from average of Opening Time respect to CyP time period like following
diagram:

With opening percentage we mean percentage of cycle period where valve is open. For example, if
CyP=6s and we say: “The valve opening percentage is 50%”; we mean the valve is opened for 3s
during cycle period.

3.1 INJECTION SIGNALLING

The graph illustrates how to work the function for injection problems signalling. When superheat stays
in dSH (delta SuperHeat) band and valve increases continuously its opening more than dOP (delta
OPening) for ind time (injection delay) the driver signals a gas problem. When this event occurs, the
behaviour of the valve can be fitted to your demand. Trough inb (injection behaviour) parameter you
can choose if the valve have to close completely (inb=cL) , or if regulation have to continue normally
with PI.

1

4. FRONT PANEL

XEV11D

To display and to modify the set
point. In programming mode it
selects a parameter or it
confirms a value.
In programming mode it slides
the codes of the parameters or it
increases their values.
In programming mode it slides
the codes of parameters or it
decreases their values.

KB1-PRG

KEYS COMBINATIONS

+

To lock or to unlock the keyboard.

+

To enter to programming mode.

+

Press and hold this keys combination about 5 seconds to activate
valve ON function (described in Plant start section). If you are in
programming mode this combination permits to leave it.

4.1 XEV11D LEDS

XEV11D has four LEDs. Their meaning is described in the following table:

LED MODE Function

POWER

ON The power supply is ok

TX/RX

OFF There is no RS485 activity

TX/RX

BLINKING Serial communication present

VALVE

ON Valve is opened

dIXEL

Operating instruction manual

1592019010

1592019010 XEV11D GB r1.2 2008.07.08.doc XEV11D 2/4

LED MODE Function

VALVE

OFF Valve is closed

ALARM

ON Alarm present

ALARM

OFF There is no alarm

5. USER INTERFACE

5.1 TO SEE THE READ-ONLY PARAMETERS

1) Press and release o key;

2) First read-only label is showed;

3) Slide labels with o or narrows;

4) Press SET to see read-only value, to change value to see press SET

5) To leave, press and release o+ SET or wait time-out of about 3 minutes.

5.2 TO SEE THE SET POINT

1) Press the SET key until the set point will be showed;

2) To come back to see temperature, wait about 5s or press newly SET key.

5.3 TO MODIFY THE SET POINT

To change the set point value operate as follows:

1) Press the SET key until the set point will be showed;

2) Use o or n to change its value.

3) Press “SET” to store the new value.

5.4 TO GO TO “PR1” PARAMETERS

To enter in “Pr1” level menu:

1) Pressing SET+ nkeys for about 3 seconds.

2) Instruments shows first parameter in Pr1 menu

5.5 TO GO TO “PR2” PARAMETERS

To enter to “Pr2” parameters list:

1. Enter to “Pr1”

2. Select “Pr2” parameter and press SET

3. The “PAS” label will be shown, then “0 - - “ with 0 blinking.

4. Insert “321” password through o and n keys, then press SET to

confirm.

5.6 TO MODIFY THE PARAMETERS VALUE

To change the parameter’s value operate as
follows:

1. Enter the Programming mode by
pressing the Set and DOWN key for
about 3s.

2. Select the required parameter.

3. Press the “SET” key to display its value

4. Use o or n to change its value.

5. Press “SET” to store the new value and move to the following parameter.

To exit: Press SET + o or wait 30s without pressing a key.
NOTE: the set value is stored even when the procedure is exited by waiting the time-out to expire.

6. PARAMETERS LIST

NOTE: All pressure parameters are relatives or absolutes depending on PrM parameter.

REGULATION
FtY Kind of gas (R22, 134, 404, 407, 410, 507, CO2): Type of gas used by plant.

Fundamental parameter for correct functioning of all system.

PEO Probe Error opening percentage: (0÷100%) if a temporary probe error occurs, valve

opening percentage is PEo until PEd time is elapsed.

PEd Probe Error delay before stopping regulation: (0÷239 sec. – 240=unlimited) if probe

error duration is bigger than PEd then valve totally closes. If PEd=240 valve opening is
PEo until probe error finishes.

ESF Enable Start Function: (n÷Y) n= when digital input configured as CCL is activated, normal

regulation starts immediately; Y= when digital input configured as CCL is activated valve
opens with OPE percentage for time SFd.

OPE Start opening Percentage: (0÷100%) Opening valve percentage when start function is

active and during post defrost phase. This phase duration is SFd time.

SFd Start Function duration: (0.0÷42.0 min: tens of seconds) It sets start function duration

and post-defrost duration. During this phase the alarms are neglected

ind injection delay: (0.0÷42.0 min: tens of seconds) view paragraph 3.1
dSH delta SuperHeat: (0.1÷10°C / 1÷50°F) view paragraph 3.1
dOP delta Opening Percentage: (0÷100%) view paragraph 3.1
inb injection behaviour: (rEG ÷ cL) when an injection problem is signalled if inb=cL valve will

close completely, if inb=rEG valve will regulate normaly by PI (see paragraph 3.1).

Sti Stop regulation interval: (0.0÷24.0 hours: tens of minutes) after regulating

continuously for Sti time, the valve closes for Std time in order to prevent ice creation.

Std Stop duration: (0÷60 min.) it defines stop regulation time after Sti. During this stop display

shows StP message

MnF Maximum opening percentage at normal Functioning: (0÷100%) during regulation it

sets the maximum valve opening percentage.

FOt Forced Opening time-out: (0.0÷24.0 hours: tens of minutes) If Plant starting function is

enabled for all FOt time the function is disabled automatically, see Plant starting function
paragraph.

PI PARAMETERS (trained staff)

CyP Cycle Period: (1 ÷ 15s) it permits to set cycle time.
Pb Proportional band: (0.1 ÷ 50.0 / 1÷90°F) PI proportional band
rS Band Offset: (-12.0 ÷ 12.0°C / -21÷21°F) PI band offset
inC Integration time: (0 ÷ 255s) PI integration time

PROBE PARAMETERS

tPP type of Pressure transducer: (PP – LAn) it sets type of pressure transducer to use: PP=

4÷20mA pressure transducer or ratiometric transducer 0÷5V, LAn= the pressure signal
arrives from another XEV module.

PA4 Probe value At 4mA or At 0V: (-1.0 ÷ P20 bar / -14 ÷ PSI / -10 ÷ P20 kPA*10) pressure

value measured by probe at 4mA or at 0V (related to PrM parameter)

P20 Probe value 20mA or At 5V: (PA4 ÷ 50.0 bar / 725 psi / 500 kPA*10) pressure value

measured by probe at 20mA or at 5V (related to PrM parameter)

oPr Pressure probe calibration: (-12.0 ÷ 12.0 bar / -174÷174 psi / -120 ÷ 120 kPA*10)
ttE type of tEmperature probe: (PtM ÷ Ntc) it allows to set the kind of probe used by the

instrument: PtM = Pt1000, ntC = NTC probe.

otE Temperature probe calibration: (-12.0 ÷ 12.0 °C / -21÷21 °F)

DIGITAL INPUTS

i1P Digital Input 1 (Free of voltage) digital input polarity: (cL,OP) CL= activated when

closed; OP= activated when opened

i1F Digital Input 1 (Free of voltage) digital input function: (CCL, rL, dEF) CCL= cooling

call; rL= digital input activates relay; dEF= digital input signals that defrost is active

d1d Digital Input 1 (Free of voltage) activation delay: (0÷255 min.) this activation delay is

used only if digital input is configured as rL

i2P Digital Input 2 (High voltage) digital input polarity: (CL,OP) CL= activated when closed;

OP=activated when opened

i2F Digital Input 2 (High voltage) digital input function: (CCL, rL, dEF) CCL= cooling call;

rL= digital input activates relay; dEF= digital input signals that defrost is active

d2d Digital Input 2 (High voltage) activation delay: (0÷255 min.) this activation delay is used

only if digital input is configured as rL

ALARM

dAO Alarm delay after restarting regulation: (0.0÷42.0 min: tens of seconds) time between

digital input activation (configured as CCL) and alarm signalling

tdA Type of alarm signalled by relay: (ALL, SH, PrE, di, LOC, inJ) ALL= all alarm; SH=

superheat alarm; PrE= pressure alarm; di= activation only when digital input configured as
rL is actived; LOC= lock alarm in case of nPA events reached; inJ= activation in cases of
injection alarm.

LPL Lower Pressure Limit for superheat regulation: (PA4 ÷ P20 bar / psi / kPA*10) when

suction pressure comes down to LPL the regulation is performed with a LPL fixed value for
pressure, when pressure comes back to LPL the normal pressure value is used. (related to
PrM parameter)

MOP Maximum Operating Pressure threshold: (PA4 ÷ P20 bar / psi / kPA*10) if suction

pressure exceeds maximum operating pressure value, instrument signals situation with
alarm LED

. (related to PrM parameter)

LOP Lowest Operating Pressure: (PA4 ÷ P20 bar / psi / kPA*10) if the suction pressure

comes down to this value a low pressure alarm is signalled with alarm LED

. (related to

PrM parameter)

PHy Pressure alarm Hysteresis: (0.1 ÷ 5.0 bar / 1÷ 72 PSI / 1÷50 kPA*10) alarm hysteresis

to disable alarm signalling.

dML delta MOP-LOP: (0 ÷ 100%) when a MOP alarm occurs valve will close of the dML

percentage every cycle period until MOP alarm is active. When LOP occurs valve will open
of the dML percentage every cycle period until LOP alarm is active.

tPA Maximum time between two MOP and/or LOP events: (0.0÷42.0 min: tens of

seconds) time interval to calculate the number of the pressure switch activation.

nPA Number of events before locking: (0=Off ÷ 100) number of MOP or LOP events, during

the “tPA” interval, before locking instrument.

MSH Maximum SuperHeat alarm: (LSH÷32,0°C / LSH÷176°F) when superheat exceeds this

value an high superheat alarm is signalled after interval SHd

LSH Lowest SuperHeat alarm: (0.0÷MSH °C / 32÷MSH °F) when superheat goes down to this

value a low superheat alarm is signalled after interval SHd

SHy SuperHeat alarm Hysteresis: (0.0÷25.5°C / 1÷77°F) hysteresis for superheat alarm

deactivation

SHd SuperHeat alarm activation delay: (0÷255s) when a superheat alarm occurs, the time

SHd have to pass before signalling alarm

FrC Fast-recovery Constant: (0÷100s) permits to increase integral time when SH is below the

set-point. If FrC=0 fast recovery function is disabled.

DISPLAY

Lod Local display:(SH, PEr, P1, P2) SH= superheat; PEr = valve opening percentage; P1=

value of temperature measured; P2= pressure measured by P2 probe;

CF Temperature measurement units: (°C÷°F) °C= Celsius degree; °F= Fahrenheit degree;

ATTENTION: by changing measurement unit, the regulation parameters have to be

correctly changed

PMu Pressure Measurement units: (bAr, PSI, kPA*10) bAr= bar; PSI= psi; PA= KPa*10;

ATTENTION: by changing measurement unit, the regulation parameters have to be

correctly changed

PrM Pressure visualization Mode: (rEL÷AbS) rEL= relative pressure; AbS= absolute

pressure;

CLt CooLing time statistic: (0÷48h) time interval used to evaluate a cooling call statistic.

During this time comes calculated how much time the cooling call is remained active

CLP CooLing Percentage (read only): Display the percentage of time during which the cooling

call was active in the time interval defined by parameter CLt

tP1 temperature Probe value (read only): it shows temperature probe value from P1