Digital controller for medium-low temperature
refrigeration applications
XW60LS
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.
•
Dixell Srl reserves the right to change the composition of its products, even without notice, ensuring
the same and unchanged functionality.
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.r.l.” (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
Model XW60LS, format 38x185mm, is microprocessor based controller, suitable for applications on
medium or low temperature ventilated refrigerating units. It has 3 relay outputs to control compressor,
fan and defrost, which can be either electrical or reverse cycle (hot gas) It could be provided with a
Real Time Clock which allows programming of up to 6 daily defrost cycles, divided into holidays and
workdays. A “Day and Night” function with two different set points is fitted for energy saving. It is also
provided with up to three NTC or PTC probe inputs, the first one for temperature control, the second
one, to be located onto the evaporator, to control the defrost termination temperature and to managed
the fan. Third probe can operates as digital input.
The HOT KEY output allows to connect the unit, by means of the external module XJ485-CX, to a
network line ModBUS-RTU compatible such as the
dIXEL
monitoring units of X-WEB family. It
allows to program the controller by means the HOT KEY programming keyboard.
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
Two defrost modes are available through the “tdF” parameter: defrost through electrical heater (tdF =
EL) and hot gas defrost (tdF = in).
The defrost interval depends on the presence of the RTC (optional). If the RTC is present is controlled
by means of parameter “EdF”:
-
with EdF=in the defrost is made every “IdF” time – standard way for controller without RTC.
-
with EdF = “rtc”, the defrost is made in real time depending on the hours set in the parameters
Ld1..Ld6 on workdays and in Sd1…Sd6 in holidays;
Other parameters are used to control defrost cycles: its maximum length (MdF) and two defrost
modes: timed or controlled by the evaporator’s probe (P2P).
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.
3.3
CONTROL OF EVAPORATOR FANS
The fan control mode is selected by means of the “FnC” parameter:
FnC = C_n: fans will switch ON and OFF with the compressor and not run during defrost;
FnC = o_n fans will run even if the compressor is off, and not run during defrost;
After defrost, there is a timed fan delay allowing for drip time, set by means of the “Fnd” parameter.
FnC = C_Y fans will switch ON and OFF with the compressor and run during defrost;
FnC = o_Y fans will run continuously also during defrost
An additional parameter “FSt” provides the setting of temperature, detected by the evaporator probe,
above which the fans are always OFF. This is used to make sure circulation of air only if his
temperature is lower than set in “FSt”.
3.3.1 Forced activation of fans
This function managed by the Fct parameter is designed to avoid short cycles of fans, that could
happen when the controller is switched on or after a defrost, when the room air warms the evaporator.
Functioning: if the difference of temperature between the evaporator and the room probes is more
than the value of the Fct parameter, the fans are switched on. With Fct=0 the function is disabled.
3.3.2 Cyclical activation of the fans with compressor off.
When Fnc = c-n or c-Y (fans in parallel to the compressor), by means of the Fon and FoF parameters
the fans can carry out on and off cycles even if the compressor is switched off. When the compressor
is stopped the fans go on working for the Fon time. With Fon =0 the fans remain always off, when the
compressor is off.
4.
FRONT PANEL COMMANDS
4.1
STANDARD FRONTAL PANEL
4.2
STEEL FINISHING
: To display target set point; in programming mode it selects a parameter or confirm an
operation.
(DEF)
To start a manual defrost
(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, if onF = oFF.
NOT USED.
KEY COMBINATIONS:
+
To lock & unlock the keyboard.
+
To enter in programming mode.
+
To return to the room temperature display.
4.3
USE OF LEDS
Each LED function is described in the following table.
LED MODE
FUNCTION
ON
Compressor enabled
Flashing Anti-short cycle delay enabled
ON
Defrost enabled
Flashing Drip time in progress
ON
Fans enabled
Flashing Fans delay after defrost in progress.
ON
An alarm is occurring
ON
Continuous cycle is running
ON
Energy saving enabled
°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
n
key.
2.
The “Lo” message will be displayed followed by the minimum temperature recorded.
3.
By pressing the
n
key again or by waiting 5s the normal display will be restored.
5.2
HOW TO SEE THE MAX TEMPERATURE
1.
Press and release the
o
key.
2.
The “Hi” message will be displayed followed by the maximum temperature recorded.
3.
By pressing the
o
key again or by waiting 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 will be displayed)
2.
To confirm the operation the “rSt” message starts blinking and the normal temperature will be
displayed.
1592027350 XW60LS RTC GB r1.0 18.03.2015
XW60LS
1/5
