Emerson Dixell XR44CX Wiring diagram

1598024001 XR44CX ISA GB r1.0 26.01.2007 XR44CX 1/3
Digital controller with defrost and fans management
XR44CX
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 instrumentback tothe distributorwithadetaileddescription
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
Model XR44CX, format 32 x 74 mm, is microprocessor based controller, suitable for applications on
low temperature refrigerating units. It has four relay outputs to control compressor 1 and 2, defrost 1
and 2, which can be either electrical or reverse cycle (hot gas). It is also provided with up to three
NTC or PTC probe inputs, the first one for temperature control, the second and third one, to be
located onto the evaporator, to control the defrost termination temperature on the evaporator 1 and 2.
It allows to program the controller by means the HOT KEY programming 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.
Time
Temper.
Compr.
SET
ON
In case of fault in the thermostat probe the start and stop of the compressor are timed through
parameters “COn” and “COF”.
3.2 2ND COMPRESSOR MANAGEMENT
The relay of the second compressor is activated in parallel with the relay of the first compressor, with
a possible delay set in the AC1 parameter. Both the compressors are switched off at the same time.
3.3 DEFROST
Two defrost modes are available through the “tdF”parameter: defrost through electricalheater (tdF =
EL) and hot gas defrost (tdF = in). Other parameters are used to control the interval between
defrost cycles (IdF), its maximum length (MdF and MdS) and two defrost modes: timed or controlled
by the evaporator’s probe (P2P and P3P).
At the end of defrost dripping time is started, its length is set in the Fdt parameter. With Fdt =0 the
dripping time is disabled.
This instrument can manage up to 2 evaporators; the XR44CX waits till the defrost termination on
both evaporators before restart with the normal temperature control.
4. FRONT PANEL COMMANDS
: To display target set point; in programming mode it selects a parameter or confirm an
operation.
(DEF) To start a manualdefrost
(UP): To see the max. stored temperature; in programming mode it browses the parameter
codes or increases the displayed value.
(DOWN) To see the min stored temperature; in programming mode it browses the parameter
codes or decreases the displayed value.
To switch the instrument off and on.
Not used.
KEY COMBINATIONS:
+  To lock & unlock the keyboard.
+To enter in programming mode.
+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/s enabled
Flashing Programming phase (flashing with )
Anti-short cycle delay enabled
ON Defrost enabled
Flashing Programming phase (flashing with )
Drip time in progress
ON An alarm is occurring
°C/°F ON Measurement unit
°C/°F Flashing Programming phase
5. MAX & MIN TEMPERATURE MEMORIZATION
5.1 HOW TO SEE THE MIN TEMPERATURE
1. Press and release the nkey.
2. The “Lo” message will be displayed followed by the minimum temperature recorded.
3. By pressing the nkeyagain or bywaiting 5s the normal display will be restored.
5.2 HOW TO SEE THE MAX TEMPERATURE
1. Press and release the okey.
2. The “Hi” message will be displayed followed by the maximum temperature recorded.
3. By pressing the okeyagain or bywaiting 5s the normal display will be restored.
5.3 HOW TO RESET THE MAX AND MIN TEMPERATURE RECORDED
1. Hold press the SET key for more than 3s, while the max. or min temperature is displayed. (rSt
message willbe displayed)
2. To confirm the operation the “rSt” message starts blinking and the normal temperature will be
displayed.
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 immediatelyrelease 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 willbe displayed and the LED starts blinking;
3. To change the Set value push the o or narrows within 10s.
4. To memorise the new set point value push the SET keyagain or wait 10s.
6.3 HOW TO START A MANUAL DEFROST
Push the DEF key for more than 2 seconds and a manualdefrost will start.
6.4 HOW TO CHANGE A PARAMETER VALUE
To change the parameter’s value operate as follows:
1. Enter the Programming mode by pressing the Set + nkeys for 3s (the or LED start
blinking).
2. Select the required parameter. Press the “SET” keyto display its value
3. Use “UP”or “DOWN”to change its value.
4. 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.
6.5 THE HIDDEN MENU
The hidden menu Includes all the parameters of the instrument.
6.5.1 HOW TO ENTER THE HIDDEN MENU
1. Enter the Programming mode by pressing the Set + nkeys for 3s (the “°C” or “°F” LED starts
blinking).
2. Released the keys, then push again the Set+nkeys for more than 7s. The Pr2 label will be
displayed immediatelyfollowed from the HY parameter.
NOW YOU ARE IN THE HIDDEN MENU.
3. Select the required parameter.
4. Press the “SET” key to display its value
5. Use o or nto 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.
NOTE1: if none parameter is present in Pr1, after 3s the “noP” message is displayed. Keep the keys
pushed tillthe Pr2 message is displayed.
NOTE2: the set value is stored even when the procedure is exited by waiting the time-out to expire.

1598024001 XR44CX ISA GB r1.0 26.01.2007 XR44CX 2/3
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 Levelthe decimal point is on.
6.6 HOW TO LOCK THE KEYBOARD
1. Keep pressed for more than 3 s the UP + DOWN 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 willbe displayed.
6.7 TO UNLOCK THE KEYBOARD
Keep pressed together for more than 3s the o and nkeys, 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 to maintain the “ccS” set point 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.
6.9 THE ON/OFF FUNCTION
With “onF = oFF”, pushing the ON/OFF key, the instrument is switched off. The “OFF”
message is displayed. In this configuration, the regulation is disabled.
To switch the instrument on, push again the ON/OFF key.
WARNING: Loads connected to the normally closed contacts of the relays are always
supplied and under voltage, even if the instrument is in stand by mode.
7. PARAMETERS
REGULATION
Hy Differential: (0,1 ÷ 25,5°C / 1÷255°F) Intervention differentialfor set point. Compressor Cut IN is
Set Point + differential (Hy). Compressor Cut OUT is when the temperature reaches the set
point.
LS Minimum set point: (- 50°C÷SET/-58°F÷SET): Sets the minimum value for the set point.
US Maximum set point: (SET÷110°C/ SET÷230°F). Set the maximum valuefor set point.
Ot Thermostat probe calibration: (-12.0÷12.0°C; -120÷120°F) allows to adjust possible offset of
the thermostat probe.
P2P Evaporator probe presence: n= not present: the defrost stops bytime; y= present: the defrost
stops by temperature.
OE Evaporator probe calibration: (-12.0÷12.0°C; -120÷120°F). allows to adjust possible offset of
the evaporator probe.
P3P Second evaporator probe presence (P3): n= not present:, the terminal operates as digital
input.; y= present:, the terminaloperates as third probe.
O3 Second evaporator probe calibration (P3): (-12.0÷12.0°C; -120÷120°F). allows to adjust
possible offset of the third probe.
odS Outputs activation delay at start up: (0÷255min) This function is enabled at the initialstart 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.
AC1 2nd compressor delay at start up (0÷255s) Time intervalbetween the switching on of the first
compressor and the second one.
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.
CCS Set point for continuous cycle: (-50÷150°C) it sets the set point used during the continuous
cycle.
COn Compressor ON time with faulty probe: (0÷255 min) time during which the compressor is
active in case of faultythermostat 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 faultythermostat probe. With COF=0 compressor is always active.
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 decimalpoint display.
Lod Instrument display: (P1; P2, SET, dtr): it selects which probe is displayed by the instrument:
P1 = Thermostat probe; P2 = Evaporator probe; SET = set point; dtr = not set it.
DEFROST
tdF Defrost type: EL = electricalheater; in = hot gas
dtE First defrost termination temperature: (-50÷50 °C/ -58÷122°F) Enabled only when P2P=y. It
sets the temperature measured by the evaporator probe, which causes the end of defrost.
dtS Second termination temperature: (-50÷50 °C/ -58÷122°F) Enabled only when P3P=y. It sets
the temperature measured by the second evaporator probe, which causes the end of defrost.
IdF Interval between defrost cycles: (0÷120h) Determines the time interval between the
beginning of two defrost cycles.
MdF (Maximum) length for first 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.
MdS (Maximum) length for second defrost: (0÷255min) When P3P = n, (not evaporator probe:
timed defrost) it sets the defrost duration, when P3P = y (defrost end based ontemperature) it
sets the maximum length for defrost.
dSd Start defrost delay: ( 0÷99min) This is useful when different defrost start times are necessary
to avoid overloading the plant.
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 realroom temperature display.
Fdt Drip time: (0120 min) time interval between reaching defrost termination temperature and the
restoring of the control’s normal operation. This time allows the evaporator to eliminate water
drops that might have formed due to defrost.
dPo First defrost after start-up: (y = immediately; n = after the IdF time)
dAF Defrost delay after continuous cycle: (023.5h) time interval between the end of the fast
freezing cycle and the following defrost related to it.
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.
AFH Differential for temperature alarm/ fan recovery: (0,1÷25,5°C; 1÷45°F) Intervention
differential for recovery of temperature alarm. It’s also used for the restart of the fan when the
FSt temperature is reached
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 betweenthe
detection of the temperature alarm condition after instrument power on and alarm signalling.
OTHER
Adr Serial address (0÷244): Identifies the instrument address when connected to a ModBUS
compatible monitoring system.
PbC Type of probe: it allows to set the kind of probe used by the instrument: PbC = PBC probe, ntc
= NTC probe.
dP1 Thermostat probe display
dP2 Evaporator 1 probe display
dP3 Evaporator 2 probe display
rSE Real set point: it shows the set point used during the energy saving cycle or during the
continuous cycle.
rEL Software release for internaluse.
Ptb Parameter table code: readable only.
8. INSTALLATION AND MOUNTING
Instrument XR44CX shall be mounted on vertical panel, in a 29x71
mm hole, and fixed using the specialbracket supplied.
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.
9. ELECTRICAL CONNECTIONS
The instrument is provided with screw terminal block to connect cables with a cross section up to 2,5
mm2. Before connecting cables make sure the power 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.
9.1 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.
10. HOW TO USE THE HOT KEY
10.1 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 okey; the "uPL" message
appears followed a by flashing “End”
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 okey if you
want to restart the upload again or remove the “Hot key”to abort the operation.
10.2 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 willrestart 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.
11. ALARM SIGNALS
Message Cause Outputs
“P1” Room probe failure Compressor output acc. to par. “Con” and “COF”
“P2” Evaporator probe failure Defrost end is timed
“HA” Maximum temperature alarm Outputs unchanged.
“LA” Minimum temperature alarm Outputs unchanged.
“dA” Door open Compressor and fans restarts
“EA” External alarm Output unchanged.
“CA” Serious externalalarm (i1F=bAL) Alloutputs OFF.
“PAL” Pressure switch alarm (i1F=PAL) All outputs OFF

1598024001 XR44CX ISA GB r1.0 26.01.2007 XR44CX 3/3
11.1 ALARM RECOVERY
Probe alarms P1”, “P2”, “P3” start some seconds after the fault in the related probe; they
automatically stop some seconds after the probe restarts normaloperation. Check connections before
replacing the probe.
Temperature alarms “HA”, “LA” automatically stop as soon as the temperature returns to normal
values.
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.
12. TECHNICAL DATA
Housing: self extinguishing ABS.
Case: frontal32x74 mm; depth 60mm;
Mounting: panelmounting in a 71x29mm panelcut-out
Protection: IP20; Frontal protection: IP65
Connections: Screw terminalblock 2,5 mm2wiring.
Power supply: according to the model: 12Vac/dc, ±10%.
Power absorption: 3VA max.
Display: 3 digits, red LED, 14,2 mm high; Inputs: Up to 4 NTC or PTC probes.
Digital input: free voltage contact
Relay outputs: compressor 1, 2 relay16(6)A 250Vac
defrost 1, 2: relay 16(6)A 250Vac
Buzzer: optional.
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: -25÷60 °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 °F (selectable); Accuracy (ambient temp. 25°C): ±0,7 °C ±1 digit
13. CONNECTIONS
14. DEFAULT SETTING VALUES
Label
Value Level Name Range
Set -5.0 - - - Set point LS÷US
Hy 2.0 Pr1 Differential 0,125.5°C/ 145°F
LS -40.0
Pr2 Minimum set point -550°CSET/-67°FSET
US
110 Pr2 Maximum set point SET150°C/ SET 302°F
Ot 0.0 Pr1 Thermostat probe calibration -1212°C /-2121°F
P2P Y Pr1 Evaporator probe presence n=not present; Y=pres.
OE
0.0 Pr2 Evaporator probe calibration -1212°C /-2121°F
P3P y Pr2 Third probe presence n=not present; Y=pres.
O3 0 Pr2 Third probe calibration -1212°C /-2121°F
OdS 0 Pr2 Outputs delay at start up 0÷255 min
AC
1 Pr1 Anti-short cycle delay 0 50 min
AC1 5 Pr1 2nd compressor delay at start up 0÷255 sec
CCt 0.0 Pr2 Continuos cycle duration 0.0÷24.0h
CCS 0 Pr2 Set point for continuous cycle (-55.0÷150,0°C) (-67÷302°F)
COn
15 Pr2 Compressor ON time with faulty probe 0 255 min
CoF
15 Pr2 Compressor OFF time with faulty probe 0 255 min
CF °C Pr2 Temperature measurement unit °C °F
rES dE Pr1 Resolution in=integer; dE= dec.point
Lod P1 Pr2 Probe displayed P1;P2; SEt ; dtr
tdF EL Pr2 Defrost type EL=el. heater; in= hot gas
dtE 8 Pr1 First Defrost termination temperature -55 50 °C
dtS 8 Pr1 Second Defrost termination temperature -55 50 °C
IdF 6 Pr1 Intervalbetween defrost cycles 1 120 h
MdF 30 Pr1 (Maximum) length for defrost 1 0 255 min
MdS 30 Pr1 (Maximum) length for defrost 2 0 255 min
dSd 0 Pr2 Start defrost delay 0÷255 min
dFd it Pr2 Displaying during defrost rt, it, SEt, DEF
dAd 30 Pr2 MAX display delay after defrost 0 ÷ 255 min
Fdt 0 Pr2 Draining time 0÷255 min
dPo
n Pr2 First defrost after startup n=after IdF; y=immed.
dAF 0.0 Pr2 Defrost delay after fast freezing 0 ÷ 24h
ALc
Ab Pr2 Temperat. alarms configuration rE= related to set;
Ab = absolute
ALU 110 Pr1 MAXIMUM temperature alarm Set110.0°C; Set÷230°F
ALL -50.0 Pr1 Minimum temperature alarm -50.0°CSet/ -58°FSet
AFH 1 Pr2 Differentialfor temperat. alarm recovery (0,1°C÷25,5°C) (1°F÷45°F)
ALd
10 Pr2 Temperature alarm delay 0 255 min
dAO
1.3 Pr2 Delay of temperature alarm at start up 0 24h
Adr 1 Pr2 Serial address 0÷247
PbC ntc Pr2 Type of probe Ptc; ntc
Label
Value Level Name Range
dP1 -- Pr2 Room probe display Probe value
dP2 -- Pr1 First Evaporator probe display Probe value
dP3 -- Pr1 Second evaporator probe display Probe value
rSE -- Pr2 Realset point actualset
rEL -- Pr2 Software release Read only
Ptb -- Pr2 Map code Read only