Cold Stream XR20C Installation Manual

dIXEL

A

A

Installing and Operating Instructions

Digital controller with off cycle defrost

XR20C – XR20D

1592007211

CONTENTS

1. GENERAL WARNING __________________________________________ 1

2. GENERAL DESCRIPTION_______________________________________ 1

3. CONTROLLING LOADS ________________________________________ 1

4. FRONT PANEL COMMANDS ____________________________________ 1

5. TEMPERATURE ALARM AND ITS DURATION RECORDING (HACCP) ___1

6. MAIN FUNCTIONS_____________________________________________ 2

7. PARAMETERS________________________________________________ 2

8. DIGITAL INPUT (IF AVAILABLE)__________________________________ 2

9. INSTALLATION AND MOUNTING_________________________________3

10. ELECTRICAL CONNECTIONS ___________________________________3

11. HOW TO USE THE HOT KEY ____________________________________3

12. ALARM SIGNALS______________________________________________ 3

13. TECHNICAL DATA_____________________________________________ 3

14. CONNECTIONS _______________________________________________ 3

15. DEFAULT SETTING VALUES ____________________________________ 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

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

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

• Warning: disconnect all electrical connections before any kind of

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

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

• Consider the maximum current which can be applied to each relay (see

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

• In case of applications in industrial environments, the use of mains filters (our

SAFETY PRECAUTIONS

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

maintenance.

not be opened.

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

Technical Data).

and far enough from each other, without crossing or intertwining.

mod. FT1) in parallel with inductive loads could be useful.

2. GENERAL DESCRIPTION

Models XR20C, format 32 x 74 mm, and XR20D, DIN rail format, are thermostats
with off cycle defrost designed for refrigeration applications at normal temperature.
They have a relay output to drive the compressor and a PTC or NTC probe input.
A internal timer manages the off cycle defrost. The instrument is fully configurable
through special parameters that can be easily programmed through the keyboard.

3. CONTROLLING LOADS

3.1 COMPRESSOR

The regulation is performed according to the temperature measured by the
thermostat probe with a positive differential from the set point: if the temperature
increases and reaches set point plus differential the compressor is started and
then turned off when the temperature reaches the set point value again.

In case of fault in the thermostat probe the start and stop of the compressor are
timed through parameters “COn” and “COF”.

3.2 DEFROST

Defrost is performed through a simple stop of the compressor. Parameter “IdF”
controls the interval between defrost cycles, while its length is controlled by
parameter “MdF”.

4. FRONT PANEL COMMANDS

XR20C

XR20D

SET: To display target set point; in programming mode it selects a parameter or

confirm an operation.

(DEF) To start a manual defrost

o (UP): To see the last temperature alarm happened; in programming mode it

browses the parameter codes or increases the displayed value.

n (DOWN) To see the last temperature alarm happened; in programming mode it

browses the parameter codes or decreases the displayed value.

KEY COMBINATIONS:

o + n To lock & unlock the keyboard.
SET + n To enter in programming mode.

SET + o To return to the room temperature display.

4.1 USE OF LEDS

Each LED function is described in the following table.

LED MODE FUNCTION

ON Compressor enabled

Flashin

-Programming Phase (flashing with

g

- Anti-short cycle delay enabled

ON Defrost enabled

Flashin

- Programming Phase (flashing with

g
ON An temperature alarm happened

)

)

5. TEMPERATURE ALARM AND ITS DURATION
RECORDING (HACCP)

XR20C signals and records temperature alarms, together with their duration and
max value reached. See drawing:

Ex. High temperature alarm

Temperature

Max

Temperature

Lu

High temp. alarm

Set

ALL

Low temp. alarm

X

Safe food zone

X

larm duration

X

Time

5.1 HOW TO SEE THE ALARM DURATION AND MAX (MIN)
TEMPERATURE

If the alarm LED is on, an alarm has taken place.
To see the kind of alarm, the max (min) reached temperature and alarm duration
do as follows:

1. Push the Up or Down key.

2. On the display the following message is shown::
“HAL” for high temperature alarm (“LAL” fot the minimum allarm), followed
by the Maximum (minimum) temperature.
Then the “tiM” (tiMe) message is displayed, followed by the “Duration” in
h.mm.

3. Then the instrument displays the temperature once again.

NOTE1: if an alarm is still occurring the “tim” shows the partial duration.
NOTE2: the alarm is recorded when the temperature come back to normal values

5.2 HOW TO RESET A RECORDED ALARM OR ONE THAT IS

STILL OCCURRING

1. Hold the SET key pressed for more than 3s, while the recorded alarm is

displayed. (the rSt message will be displayed)

2. To confirm the operation, the “rSt” message starts blinking and the normal

temperature will be displayed.

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Installing and Operating Instructions

6. MAIN FUNCTIONS

6.1 HOW TO SEE THE SETPOINT

1. Push and immediately release the SET key: the display will
show the Set point value;

2. Push and immediately release the SET key or wait for 5 seconds to display
the probe value again.

6.2 HOW TO CHANGE THE SETPOINT

1. Push the SET key for more than 2 seconds to change the Set point value;

2. The value of the set point will be displayed and the

3. To change the Set value push the o or n arrows within 10s.

4. To memorise the new set point value push the SET key again or wait 10s.

LED starts blinking;

6.3 HOW TO START A MANUAL DEFROST

Push the DEF key for more than 2 seconds and a manual
defrost will start.

6.4 HOW TO CHANGE A PARAMETER VALUE

To change the parameter’s value operate as follows:

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

To exit: Press SET + UP or wait 15s without pressing a key.
NOTE: the set value is stored even when the procedure is exited by waiting the

time-out to expire.

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

2. Select the required parameter.

3. Press the “SET” key to display its value (now only the
LED is blinking).

4. Use “UP” or “DOWN” to change its value.

and

start blinking).

6.5 THE HIDDEN MENU

The hidden menu Includes all the parameters of the instrument.

6.5.1 HOW TO ENTER THE HIDDEN MENU

3. Select the required parameter.

4. Press the “SET” key to display its value (Now only the

5. Use o or n to change its value.

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

To exit: Press SET + o or wait 15s without pressing a key.
NOTE: the set value is stored even when the procedure is exited by waiting the

time-out to expire.

6.5.2 HOW TO MOVE A PARAMETER FROM THE HIDDEN MENU TO THE
FIRST LEVEL AND VICEVERSA.

Each parameter present in the HIDDEN MENU can be removed or put into “THE
FIRST LEVEL” (user level) by pressing “SET + n”.
In HIDDEN MENU when a parameter is present in First Level the decimal point is
on.

1. Enter the Programming mode by pressing the Set + n

key for 3s (LED 1 and

2. When a parameter is displayed keep pressed the Set+n

for more than 7s. The Pr2 label will be displayed
immediately followed from the HY parameter.

NOW YOU ARE IN THE HIDDEN MENU.

start blinking).

LED is blinking).

6.6 HOW TO LOCK THE KEYBOARD

1. Keep pressed for more than 3 s the o and n keys.

2. The “POF” message will be displayed and the keyboard will be locked. At this

point it will be possible only to see the set point or the MAX o Min temperature
stored

3. If a key is pressed more than 3s the “POF” message will be displayed.

6.7 TO UNLOCK THE KEYBOARD

Keep pressed together for more than 3s the o and n keys, till the “Pon”
message will be displayed.

6.8 THE CONTINUOUS CYCLE

When defrost is not in progress, it can be activated by
holding the “o” key pressed for about 3 seconds.

The compressor operates in continuous mode for the time set through the “CCt”
parameter. The cycle can be terminated before the end of the set time using the
same activation key “o” for 3 seconds.

7. PARAMETERS

NOTE: the parameters preceded by dots are in the Hidden Menu.
REGULATION
Hy Differential: (0,1 ÷ 25,5°C / 1÷255 °F) Intervention differential for set point.

Compressor Cut IN is Set Point Plus Differential (Hy). Compressor Cut OUT is
when the temperature reaches the set point.

1592007211

• LS Minimum set point: (- 50°C÷SET/-58°F÷SET): Sets the minimum

acceptable value for the set point.

• US Maximum set point: (SET÷110°C/ SET÷230°F). Set the maximum

acceptable value for set point.

Ot Thermostat probe calibration: (-12.0÷12.0°C;

-120÷120°F) allows to adjust possible offset of the thermostat probe.

• OdS Outputs activation delay at start up: (0÷255min) This function is

enabled at the initial start up of the instrument and inhibits any output
activation for the period of time set in the parameter.

AC Anti-short cycle delay: (0÷50 min) minimum interval between the

compressor stop and the following restart.

• CCt Compressor ON time during continuous cycle: (0.0÷24.0h; res.

10min) Allows to set the length of the continuous cycle: compressor stays on
without interruption for the CCt time. Can be used, for instance, when the
room is filled with new products.

• COn Compressor ON time with faulty probe: (0÷255 min) time during which

the compressor is active in case of faulty thermostat probe. With COn=0
compressor is always OFF.

• COF Compressor OFF time with faulty probe: (0÷255 min) time during

which the compressor is OFF in case of faulty thermostat probe. With COF=0

compressor is always active.

CH Type of action: CL = cooling; Ht = heating.
DISPLAY

• CF Temperature measurement unit:

°C=Celsius; °F=Fahrenheit. WARNING: When the measurement unit is
changed the SET point and the values of the parameters Hy, LS, US, Ot,
ALU and ALL have to be checked and modified if necessary).

rES Resolution (for °C): (in = 1°C; dE = 0.1 °C) allows decimal point display.
DEFROST
IdF Interval between defrost cycles: (0÷120h) Determines the time interval

between the beginning of two defrost cycles.

MdF (Maximum) length for defrost: (0÷255min) When P2P = n, (not evaporator

probe: timed defrost) it sets the defrost duration, when P2P = y (defrost end
based on temperature) it sets the maximum length for defrost.

• dFd Temperature displayed during defrost: (rt = real temperature; it =

temperature at defrost start; SEt = set point; dEF = “dEF” label)

• dAd MAX display delay after defrost: (0÷255min). Sets the maximum time

between the end of defrost and the restarting of the real room temperature
display.

ALARMS

• ALC Temperature alarms configuration: (Ab; rE)

Ab= absolute temperature: alarm temperature is given by the ALL or ALU

values. rE = temperature alarms are referred to the set point. Temperature
alarm is enabled when the temperature exceeds the “SET+ALU” or “SET-ALL”
values.

ALU MAXIMUM temperature alarm: (SET÷110°C; SET÷230°F) when this

temperature is reached the alarm is enabled, after the “ALd” delay time.

ALL Minimum temperature alarm: (-50.0 ÷ SET°C;

-58÷230°F when this temperature is reached the alarm is enabled, after the
“ALd” delay time.

• ALd Temperature alarm delay: (0÷255 min) time interval between the

detection of an alarm condition and alarm signalling.

• dAO Exclusion of temperature alarm at startup: (from 0.0 min to 23.5h)

time interval between the detection of the temperature alarm condition after
instrument power on and alarm signalling.

DIGITAL INPUT (IF AVAILABLE)
i1P Digital input polarity: oP: the digital input is activated by opening the

contact; CL: the digital input is activated by closing the contact.

i1F Digital input configuration:

EAL = external alarm: “EA” message is displayed; bAL = serious alarm “CA”

message is displayed. PAL = pressure switch alarm, “CA” message is
displayed; dor = door switch function; dEF = activation of a defrost cycle; LHt
=not enabled; Htr = kind of action inversion (cooling – heating).

did: (0÷255 min)

with i1F= EAL or i1F = bAL digital input alarm delay: delay between the

detection of the external alarm condition and its signalling.

with i1F= dor: door open signalling delay
with i1F = PAL: time for pressure switch function: time interval to

calculate the number of the pressure switch activation.

nPS Pressure switch number: (0

switch, during the “did” interval, before signalling the alarm event (I2F= PAL).

If the nPS activation in the did time is reached, switch off and on the
instrument to restart normal regulation.

• odc Compressor status when open door: no, Fan = normal; CPr, F_C =

Compressor OFF

OTHER
PbC Type of probe: it allows to set the kind of probe used by the instrument: PbC

= PBC probe, ntC = NTC probe.

• rEL Software release for internal use.

• Ptb Parameter table code: readable only.

8. DIGITAL INPUT (IF AVAILABLE)

The free contact digital input is programmable in five different configurations by the
“i1F” parameter.

8.1 DOOR SWITCH INPUT (i1F = dor)

It signals the door status and the corresponding relay output status through the
“odc” parameter:

no, Fan = normal (any change);

÷15) Number of activation of the pressure

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CPr, F_C = Compressor OFF;
Since the door is opened, after the delay time set through parameter “did”, the
door alarm is enabled, the display shows the message “dA” and the regulation
restarts. The alarm stops as soon as the external digital input is disabled again.
With the door open, the high and low temperature alarms are disabled.

Installing and Operating Instructions

8.2 GENERIC ALARM (i1F = EAL)

As soon as the digital input is activated the unit will wait for “did” time delay before
signalling the “EAL” alarm message. The outputs status don’t change. The alarm
stops just after the digital input is de-activated.

8.3 SERIOUS ALARM MODE (i1F = bAL)

When the digital input is activated, the unit will wait for “did” delay before signalling
the “CA” alarm message. The relay outputs are switched OFF. The alarm will stop
as soon as the digital input is de-activated.

8.4 PRESSURE SWITCH (i1F = PAL)

If during the interval time set by “did” parameter, the pressure switch has reached
the number of activation of the “nPS” parameter, the “CA” pressure alarm
message will be displayed. The compressor and the regulation are stopped. When
the digital input is ON the compressor is always OFF.

If the nPS activation in the did time is reached, switch off and on the
instrument to restart normal regulation.

8.5 START DEFROST (i1F = dFr)

It starts a defrost if there are the right conditions. After the defrost is finished, the
normal regulation will restart only if the digital input is disabled otherwise the
instrument will wait until the “MdF” safety time is expired.

8.6 INVERSION OF THE KIND OF ACTION: HEATING­COOLING (i1F = Htr)

This function allows to invert the regulation of the controller: from cooling to
heating and viceversa.

8.7 DIGITAL INPUTS POLARITY

The digital input polarity depends on the “i1P” parameter.
i1P=CL: the input is activated by closing the contact.
i1P=OP: the input is activated by opening the contact

9. INSTALLATION AND MOUNTING

Instrument XR20C shall be mounted on vertical
panel, in a 29x71 mm hole, and fixed using the
special bracket supplied.
To obtain an IP65 protection grade use the front
panel rubber gasket (mod. RG-C) as shown in
figure.

Instrument XR20D shall be mounted on an omega DIN rail
The temperature range allowed for correct operation is 0÷60 °C. Avoid places
subject to strong vibrations, corrosive gases, excessive dirt or humidity. The same
recommendations apply to probes. Let air circulate by the cooling holes.

10. ELECTRICAL CONNECTIONS

The instrument is provided with screw terminal block to connect cables with a
cross section up to 2,5 mm
supply complies with the instrument’s requirements. Separate the probe cables
from the power supply cables, from the outputs and the power connections. Do not
exceed the maximum current allowed on each relay, in case of heavier loads use a
suitable external relay.

2

. Before connecting cables make sure the power

10.1 PROBE CONNECTION

The probes shall be mounted with the bulb upwards to prevent damages due to
casual liquid infiltration. It is recommended to place the thermostat probe away
from air streams to correctly measure the average room temperature. Place the
defrost termination probe among the evaporator fins in the coldest place, where
most ice is formed, far from heaters or from the warmest place during defrost, to
prevent premature defrost termination.

11. HOW TO USE THE HOT KEY

1592007211

3. Push “SET” key and the End will stop flashing.

4. Turn OFF the instrument remove the “Hot Key”, then turn it ON again.

NOTE: the “Err” message is displayed for failed programming. In this case push
again o key if you want to restart the upload again or remove the “Hot key” to
abort the operation.

11.2 HOW TO PROGRAM AN INSTRUMENT USING A HOT KEY
(DOWNLOAD)

1. Turn OFF the instrument.

2. Insert a programmed “Hot Key” into the 5 PIN receptacle and then turn
the Controller ON.

3. Automatically the parameter list of the “Hot Key” is downloaded into the
Controller memory, the “doL” message is blinking followed a by flashing

“End”.

4. After 10 seconds the instrument will restart working with the new
parameters.

5. Remove the “Hot Key”..

NOTE the message “Err” is displayed for failed programming. In this case turn the
unit off and then on if you want to restart the download again or remove the “Hot

key” to abort the operation.

12. ALARM SIGNALS

Message Cause Outputs

“P1” Room probe failure Compressor output according

“HA” Maximum temperature alarm Outputs unchanged.
“LA” Minimum temperature alarm Outputs unchanged.
“dA” Door open Regulation restarts
“EA” External alarm Output unchanged.
“CA” Serious external alarm (i1F=bAL) All outputs OFF.
“CA” Pressure switch alarm (i1F=PAL) All outputs OFF

12.1 ALARM RECOVERY

Probe alarm “P1” starts some seconds after the fault in the related probe; it
automatically stops some seconds after the probe restarts normal operation.
Check connections before replacing the probe.
Temperature alarms “HA” and “LA” automatically stop as soon as the thermostat
temperature returns to normal values and when defrost starts.
Alarms “EA” and “CA” (with i1F=bAL) recover as soon as the digital input is
disabled.
Alarm “CA” (with i1F=PAL) recovers only by switching off and on the instrument.

13. TECHNICAL DATA

Housing: self extinguishing ABS.
Case: XR20C frontal 32x74 mm; depth 60mm;

XR20D 4 DIN modules 70x85 mm; depth 61mm

Mounting: XR20C panel mounting in a 71x29mm panel cut-out

XR20D DIN RAIL mounted in a omega (3) din rail
Protection: IP20.
Frontal protection: XR20C IP65 with frontal gasket RG-C (optional).
Connections: Screw terminal block ≤ 2,5 mm
Power supply: according to the model: 12Vac/dc, ±10%; 24Vac/dc, ±10%;

230Vac ±10%, 50/60Hz, 110Vac ±10%, 50/60Hz

Power absorption: 3VA max
Display: 3 digits, red LED, 14,2 mm high.
Inputs: 1 NTC or PTC probe.
Digital input: free contact
Relay outputs

compressor: SPDT relay 8(3) A, 250Vac or

SPST relay 20(8)A; 250Vac

Data storing: on the non-volatile memory (EEPROM).
Kind of action: 1B; Pollution grade: normal; Software class: A.
Operating temperature: 0÷60 °C.
Storage temperature: -30÷85 °C.
Relative humidity: 20÷85% (no condensing)
Measuring and regulation range:

NTC probe: -40÷110°C (-40÷230°F)

PTC probe: -50÷150°C (-58÷302°F)
Resolution: 0,1 °C or 1°C or 1 °F (selectable).
Accuracy (ambient temp. 25°C): ±0,7 °C ±1 digit

to par. “Con” and “COF”

2

wiring.

11.1 HOW TO PROGRAM A HOT KEY FROM THE
INSTRUMENT (UPLOAD)

1. Program one controller with the front keypad.

2. When the controller is ON, insert the “Hot key” and push o key; the "uPL"

message appears followed a by flashing “End”

1592007211 XR20C-D GB r1.0 22.04.2005.doc XR20C – XR20D 3/4

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Installing and Operating Instructions

1592007211

14. CONNECTIONS

14.1 XR20C: 8A COMPRESSOR

8(3)A250V

12 3 6 7

N.C.

Comp

Line

12Vac/dc supply: connect to the terminals 7 and 8.
24Vac/dc supply: connect to the terminals 7 and 8.
120Vac supply: connect to the terminals 7 and 8.

8

14.2 XR20C: 20A COMPRESSOR

20(8)A250V

456 7

8

Comp

Line

12Vac/dc supply: connect to the terminals 7 and 8.
24Vac/dc supply: connect to the terminals 7 and 8.
120Vac supply: connect to the terminals 7 and 8.

14.3 XR20D: 8A COMPRESSOR

9101112

Hot Key

9101112

Hot Key

Room

Room

15. DEFAULT SETTING VALUES

Label Name Range °C/°F

Set point LS÷US 3.0/37

Set

Differential

Hy

Minimum set point

LS

Maximum set point

US

Thermostat probe calibration

Ot

Outputs delay at start up 0÷255 min 0

OdS

Anti-short cycle delay

AC

Continuos cycle duration 0.0÷24.0h

CCt

Compressor ON time with faulty

COn

probe
Compressor OFF time with faulty

COF

probe
Kind of action CL=cooling; Ht= heating CL

CH

Temperature measurement unit

CF

Resolution

rES

Interval between defrost cycles

IdF

(Maximum) length for defrost

MdF

Displaying during defrost

dFd

MAX display delay after defrost 0 ÷ 255 min 30

dAd

Temperat. alarms configuration

ALc

MAXIMUM temperature alarm

ALU

Minimum temperature alarm

ALL

Temperature alarm delay

ALd

Delay of temperature alarm at

dAO

start up
Digital input polarity oP=opening;CL=closing cL

i1P

Digital input configuration

i1F

Digital input alarm delay 0÷255min 5

did

Number of activation of pressure

Nps

switch
Compressor status with open

odc

door:
Kind of probe

PbC

Software release -- 4.0

rEL

Map code -- -

Ptb

0,1÷25.5°C/ 1÷ 255°F

-50°C÷SET/-58°F÷SET

SET÷110°C/ SET ÷ 230°F

-12÷12°C /-120÷120°F

0 ÷ 50 min

0 ÷ 255 min

0 ÷ 255 min

°C ÷ °F

in=integer; dE= dec.point

1 ÷ 120 ore

0 ÷ 255 min

rt, it, SEt, DEF

rE= related to set;

Ab = absolute

Set÷110.0°C; Set÷230°F

-50.0°C÷Set/ -58°F÷Set

0 ÷ 255 min

0 ÷ 23h e 50’

EAL=extern. alarm; bAL=lock
regulation; PAL=press. switch;
dor=door switch; dEF=defrost;

LHt=disabled; Htr= cooling -

heating

0 ÷15

no, Fan = normal;

CPr; F_C = Compr. OFF;

Ptc; ntc

2.0/4

-40,0/-40
110/230

0.0

1

0.0

15

30

°C/°F

dE/-

8

20

it

Ab

110/230

-50/-58
15

1.3

EAL

15

no

ntc/Ptc

3 4 5 6

8(3)A/250Vac

HOT KEY

13 14 15 16 17 18 19

n.c.

Comp

Line

24Vac/dc supply: connect to the terminals 11 and 12.
120Vac supply: connect to the terminals 11 and 12.
230Vac supply: connect to the terminals 11 and 12.

14.4 XR20D: 20A COMPRESSOR

Power
Supply

3 4 5 6

20(8 )A/ 250Vac

HOT KEY

15 16

Comp

Line

11 12

Power

Supply

11 12

Hidden parameters

24Vac/dc supply: connect to the terminals 11 and 12.
120Vac supply: connect to the terminals 11 and 12.
230Vac supply: connect to the terminals 11 and 12.

1592007211 XR20C-D GB r1.0 22.04.2005.doc XR20C – XR20D 4/4

Dixell S.p.A. Z.I. Via dell’Industria, 27
32010 Pieve d’Alpago (BL) ITALY
tel. +39 - 0437 - 98 33 - fax +39 - 0437 - 98 93 13

E-mail: [e-mail] - http://www.dixell.com