Hy | Differential: (0,1°C ⎟ 25°C) Intervention differential for 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: (-55°C÷SET/-58°F÷SET): Sets the minimum value for the set point.. |
US | Maximum SET POINT: (SET÷99°C/ SET÷99°F). Set the maximum value for set point. |
ot | First probe calibration: (-9.9÷9.9°C) allows to adjust possible offset of the first probe. |
P2 | Evaporator probe presence: n= not present; y= the defrost stops by temperature. (Only |
| XR04CX) |
oE | Second probe calibration: (-9.9÷9.9°C) allows to adjust possible offset of the second probe. |
| (Only XR04CX) |
od | Outputs activation delay at start up: (0÷99min) 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. |
Cy | Compressor ON time with faulty probe: (0÷99 min) time during which the compressor is active |
| in case of faulty thermostat probe. With Cy=0 compressor is always OFF. |
Cn | Compressor OFF time with faulty probe: (0÷99 min) time during which the compressor is OFF |
| in case of faulty thermostat probe. With Cn=0 compressor is always active. |
CH | Kind of Action (Only XR03CX): cL= cooling action; Ht = heating action; |
DISPLAY |
CF | Measurement unit: (°C÷°F) °C =Celsius; °F =Fahrenheit. WARNING: When the measurement |
| unit is changed the SET point and the values of the parameters Hy, LS, US, oE, o1, AU, AL |
| have to be checked and modified if necessary). |
rE | Resolution (only for °C):(dE ÷ in) dE= decimal between -9.9 and 9.9°C; in= integer |
Ld | Default display: (P1 ÷ P2) P1= thermostat probe; P2= evaporator probe. SP=Set point (Only |
| XR04CX) |
dy | Display delay: (0⎟15 min.) when the temperature increases, the display is updated of 1 °C/1°F |
| after this time. |
|
DEFROST |
td | Defrost type: (EL – in) EL= electrical heater, compressor OFF; in= hot gas, compressor ON; |
dE | Defrost termination temperature (Only XR04CX): (-50÷50°C) if P2=Y it sets the temperature |
| measured by the evaporator probe, which causes the end of defrost. |
id | Interval between defrost cycles: (0÷99 ore) Determines the time interval between the |
| beginning of two defrost cycles. |
Md | Maximum length for defrost: (0÷99 min. with 0 no defrost) when P2=n, (not evaporator probe: |
| timed defrost) it sets the defrost duration, when P2 = y (defrost end based on temperature) it sets |
| the maximum length for defrost. |
ddStart defrost delay: ( 0÷99min) This is useful when different defrost start times are necessary to avoid overloading the plant.
dF | Display during defrost: (rt / it / St / dF) rt= real temperature; it= start defrost temperature; SP= |
| SET-POINT; dF= label dF. | |
dt | Drip time: (0÷99 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. | |
dP | Defrost at power –on:(y÷n) y= at power on defrost starts; n= defrost doesn’t start at power-on |
| |
ALARMS | |
AU | Maximum temperature alarm: (AL÷99°C) when this temperature is reached | the alarm is |
| enabled, after the “Ad” delay time. | |
AL | Minimum temperature alarm: (-55÷AU°C) when this temperature is reached | the alarm is |
| enabled, after the “Ad” delay time. | |
Ad | Temperature alarm delay: (0÷99 min) time interval between the detection of an alarm condition |
| and alarm signalling. | |
dA | Exclusion of temperature alarm at startup: (0÷99 min) time interval between the detection of |
| the temperature alarm condition after instrument power on and alarm signalling. | |
tb | Silencing buzzer (n-y):(Only XR03CX) n= silencing disabled, alarm relay stays on till alarm |
| conditions lasts; y= silencing enabled: alarm relay is switched OFF by pressing a key during an |
| alarm; | |
o1 | Auxiliary relay configuration (dF/Fn/AL/AU/db): (Only XR03CX) dF= defrost; Fn= Fans; AL= |
| Alarm; AU= auxiliary; db= neutral zone; | |
AP | Alarm relay polarity (cL-OP): (Only XR03CX) cL= when active is closed; OP= when active is |
| opened | |
DIGITAL INPUT (Only XR03CX) | |
iP | Digital input polarity: (oP ÷ cL) oP= activated by closing the contact; cL= activated by opening |
| the contact; | |
iF | Digital input configuration: (EA/bA/do/dF/Au/Hc) EA= external alarm: “EA” message is |
| displayed; bA= serious alarm “CA” message is displayed; do= door switch function; dF= defrost |
| activation; Au =not used; Hc= inversion of the kind of action; | |
di | Digital input delay: (0÷99 min) with iF=EA or bA delay between the detection of the external |
| alarm condition and its signalling. . With iF=do it represents the delay to activate the door open |
| alarm. | |
dC | Compressor and fan status when open door: (no/Fn/cP/Fc): no= normal; Fn = Fans OFF; cP |
| =Compressor OFF; Fc = Compressor and fans OFF; | |
rd | Regulation with door open: (n÷y) n = no regulation if door is opened; Y= when di is elapsed |
| regulation restarts even if door open alarm is present; | |
OTHER | |
d1 | Thermostat probe display (read only) | |
d2 | Evaporator probe display (read only) (Only XR03CX) | |
Pt | Parameter code table | |
rL | Software release | |
8. DIGITAL INPUTS
The free voltage digital input is programmable in different configurations by the “iF” parameter.
DOOR SWITCH (iF=do)
It signals the door status and the corresponding relay output status through the “dC” parameter: no = normal (any change); Fn = Fan OFF; CP = Compressor OFF; FC = Compressor and fan OFF.
Since the door is opened, after the delay time set through parameter “di”, the door alarm is enabled, the display shows the message “dA” and the regulation restarts if rd = y. 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.
EXTERNAL ALARM (iF=EA)
As soon as the digital input is activated the unit will wait for “di” time delay before signalling the “EA” alarm message. The outputs status don’t change. The alarm stops just after the digital input is de- activated.
SERIOUS ALARM (iF=bA)
When the digital input is activated, the unit will wait for “di” 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.
SWITCHING SECOND RELAY ON (iF=Au)
When o1=Au it switches on and off the second relay.
START DEFROST (iF=dF)
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 “dd” safety time is expired.
INVERSION OF THE KIND OF ACTION: HEATING - COOLING (iF=Hc)
This function allows to invert the regulation of the controller: from cooling to heating and viceversa.
9. INSTALLATION AND MOUNTING
Instrument XR03CX and XR04CX shall be mounted on vertical panel, in a 29x71 mm hole, and fixed using the special bracket 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.
10.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.
1.1PROBES
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
1.2HOW TO PROGRAM THE 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 
key; the "uP" message appears followed a by flashing “Ed”
3.Push “SET” key and the “Ed” will stop flashing.
4.Turn OFF the instrument remove the “Hot Key”, then turn it ON again.
NOTE: the “Er” 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.
1.3HOW TO PROGRAM AN INSTRUMENT USING 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 “do” message is blinking followed a by flashing “Ed”.
4.After 10 seconds the instrument will restart working with the new parameters.
5.Remove the “Hot Key”..
NOTE: the “Er” 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.
12.ALARM SIGNALLING
Mess. | Cause | Outputs |
"P1" | Room probe failure | Compressor output according to “Cy” e “Cn” |
"P2" | Evaporator probe failure | Defrost end is timed (Only XR04CX) |
"HA" | Maximum temperature alarm | Outputs unchanged |
"LA" | Minimum temperature alarm | Outputs unchanged |
“EA” | External alarm | Outputs unchanged |
“CA” | Serious external alarm | All outputs OFF. |
“dA” | Door Open | Compressor and fans restarts |
1.4ALARM RECOVERY
Probe alarms P1” and “P2” start some seconds after the fault in the related probe; they automatically stop 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 temperature returns to normal values.
Alarms “EA” and “CA” (with iF=bA) recover as soon as the digital input is disabled.
13.TECHNICAL DATA
Housing: self extinguishing ABS.
Case: frontal 32x74 mm; depth 60mm;
Mounting: panel mounting in a 71x29mm panel cut-out
