dixell XM470K Installing And Operating Instructions

Dixell

1. GENERAL WARNING

Installing and Operating Instructions

XM470K

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3.4 AUXILIARY OUTPUT

The auxiliary output is switch ON and OFF by means of the corresponding button on the keyboard.

4. KEYBOARDS

There are two kind of keyboard available for the XM470K controller:.

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 operating limit s avoiding

• 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.”

• 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

• In case of applications in industrial environments, the use of mains filters (our mod. FT1) in parallel

SAF

ETY PRECAUTIONS

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

(see address) with a detailed description of the fault.

each other, without crossing or intertwining.
with inductive loads could be useful.

2. GENERAL DESCRIPTION

Model XM470K is microprocessor based controllers suitable for applications on medium or low
temperature multiplexed cabinets made of up to 5 units. It can be inserted in a LAN of up t o 5 different
sections which can operate, depending on the programming, as stand alone co ntrollers or following th e
commands coming from one of the other sections. XM470K is provided with five relay outputs to cont rol
the solenoid valve, defrost - which can be either electrical or hot gas - the evaporator fans, the light s,
and an auxiliary output. They are also provided with three NTC probe inputs, one for temperature
control, one to control the defrost end temperature of the evaporator and t he third, optional, for the
display. There are two digital inputs (free contact) one for the start of an energy saving cycle and one
fully configurable by parameter.
Two LAN output allows an easy connection between the controllers and a TTL connector for quick
programming by means of an Hot Key is also available. Direct serial output RS485 ModBUS-RTU
compatible and internal RTC are available as options.

3. CONTROLLING LOADS

3.1 THE SOLENOID VALVE

The regulation is performed according to the temperature measured by the thermostat probe wit h a
positive differential from the set point: if the temperature increases and reaches se t point plus differential
the solenoid valve is opened and then closed when the temperature reaches the set point value again.
In case of fault in the thermostat probe the opening and closing of the solenoid valve are timed through
parameters “COn” and “COF”.

3.2 DEFROST

Two defrost modes are available through the “tdF” parameter: defrost with electrical heater and hot gas
defrost. The defrost interval is control by means of parameter “EdF”: (EdF = rtc) the defrost is made in
real time depending on the hours set in the parameters Ld1..Ld8 on workdays and in Sd1…Sd8 in
holidays; (EdF = in) the defrost is made every “IdF” time, (EdF=Sd) the interval “IdF” is calculate through
Smart Defrost algorithm (only when the SOLENOID VALVE is ON and the evaporator temperature is
bigger than “SdF” parameter).
At the end of defrost the drip time is controlled through the “Fdt” parameter.
The starting of a defrost cycle can be operated locally (manual activation by means of the keyboard or
digital input or end of interval time) or the command can come from the Master defrost unit of the LAN.
In this case the controller will operate the defrost cycle following the parameters it has programmed but,
at the end of the drip time, will wait that all the other controllers of the LAN finish their defrost cycle
before to re-start the normal regulation of the temperature.
Every time any of the controller of the LAN begin a defrost cycle it issue the command into the network
making all the other controllers start their own cycle. This allows a perfect synchronisation of the defrost
in the whole multiplexed cabinet

3.3 CONTROL OF EVAPORATOR FANS

The fan control mode is selected by means of the “FnC” parameter:

C-n = running with the solenoid valve, OFF during the defrost;
C-y = running with the solenoid valve, ON during the defrost;
O-n = continuous mode, OFF during the defrost;
O-y = continuous mode, ON during the defrost;

An additional parameter “FSt” provides the setting of temperature, detected by the evaporator probe,
above which the fans are always OFF. This can be used to make sure circulation of air only if his
temperature is lower than set in “FSt”.

1592013010 XM470K GB XM470K 1/6

T840: 8 Keys, horizontal shape (185x38mm).

V840: 8 Keys, vertical shape (64x100mm).

To display and modify target set point; in programming mode it selects a parameter or
confirm an operation.
By holding it pressed for 3s when max or min temperature is displayed it will be erased.
By pressing it when the current time is displayed, it allows the User to re-set the current time
and three holidays.

To see the max. stored temperature; in programming mode it browses the parameter codes
or increases the displayed value.
By holding it pressed for 3s the give access to the “Section” menù.

To see the min stored temperature; in programming mode it browses the parameter codes or
decreases the displayed value.
By holding it pressed for 3s the current time is displayed and it permits the User to enter
Energy saving, Defrost and Clock parameter menu.

By holding it pressed for 3s the defrost is started.
By pressing it when the current time is displayed, it allows the User to set defrost times.

Switch ON and OFF the cold room light.
By holding it pressed for 3s Energy Saving function is started or stopped.

By holding it pressed for 6s, the Holiday function is started or stopped.
By pressing it when the current time is displayed, it allows the User to set Energy Saving
times.

Switch ON and OFF the auxiliary output.

Switch ON and OFF the instrument.

KEY COMBINATIONS

+
+

+

4.1 USE OF LEDS

Each LED function is described in the following table.

LED MODE Function

ON The SOLENOID VALVE is running
FLASHING

To lock and unlock the keyboard.

To enter the programming mode.

To exit the programming mode.

- Programming Phase (flashing with LED

- Anti-short cycle delay enabled

)

Dixell

Installing and Operating Instructions

ON The fan is running
FLASHING

ON The defrost is enabled
FLASHING Drip time in progress
ON The controller is working in “ALL” mode
FLASHING The controller is working in remote virtual display mode
ON - ALARM signal

Programming Phase (flashing with LED

- In “Pr2” indicates that the parameter is also present in “Pr1”

)

4.2 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 or waiting for 5s the normal display will be restored.

4.3 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 or waiting for 5s the normal display will be restored.

4.4 HOW TO RESET THE MAX AND MIN TEMPERATURE RECORDED

To reset the stored temperature, when max or min temperature is displayed :

1. Press SET key until “rST” label starts blinking.

N.B. After the installation RESET the temperature stored .

4.5 HOW TO SEE AND MODIFY THE SET POINT

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

2. The SET LED start blinking;

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

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

4.6 TO START A MANUAL DEFROST

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

4.7 TO ENTER IN PARAMETERS LIST “PR1”

To enter the parameter list “Pr1” (user accessible parameters) operate as follows:

1. Enter the Programming mode by pressing the Set and DOWN key for few
seconds (

2. The instrument will show the first parameter present in “Pr1”

and

start blinking).

4.8 TO ENTER IN PARAMETERS LIST “PR2”

To access parameters in “Pr2”:

1. Enter the “Pr1” level.

2. Select “Pr2” parameter and press the “SET” key.

3. The “PAS” flashing message is displayed, shortly followed by “0 - -” with a flashing zero.

4. Use oor n to input the securit y code in the flashing digit; confirm t he figure by pressing “SET”.
The security code is “321“.

5. If the security code is correct the access to “Pr2” is enabled by pressing “SET” on the last digit.

Another possibility is the following: after switching ON the instrument the user can p ush Set and DO WN
keys within 30 seconds.
NOTE: each parameter in “Pr2” can be removed or put into “Pr1” (user level) by pressing “SET” + n.

When a parameter is present in “Pr1” LED

is on.

4.9 HOW TO CHANGE THE PARAMETER VALUE

1. Enter the Programming mode.

2. Select the required parameter with o or n.

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

and LED starts blinking).

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 + UP or wait 15s without pressing a key.
NOTE: the new programming is stored even when the procedure is exited by waiting the time-out.

4.10 HOW TO LOCK THE KEYBOARD

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

2. The “POF” message will be displayed and the keyboard is locked. At this point it is only
possible the viewing of the set point or the MAX o Min temperature stored and t o switch
ON and OFF the light, the auxiliary output and the instrument.

TO UNLOCK THE KEYBOARD

Keep the o and n keys pressed together for more than

3s.

4.11 ON/OFF FUNCTION

By pushing the ON/OFF key, the instrument shows “OFF” for 5 sec. and the ON/OFF LED is

switched ON.

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During the OFF status, all the relays are switched OFF and the regu lations are stopped; if a
monitoring system is connected, it does not record the instrument data and alarms.

N.B. During the OFF status the Light and AUX buttons are active.

4.12 TO SEE THE PROBE VALUES

1. Enter in “Pr2” level.

2. with o or n, select “dP1” parameter for room probe, “dP2” for evaporator probe or “dP3” for
display probe.

3. Press the “SET” key to display the relative probe value.

4. Press “SET” to move to the following parameter.

5. THE SECTION MENU

This menu allows the user to access to a particular feature of the XM series related to the LAN (Local
Area Network) of controllers.
A single keyboard, depending on the programming of this menu, is able to control either the module of
the local section of the LAN or any of the other modules of the LAN acting as a remote virtual display.
The possibilities are:
LOC: the keyboard controls and display the value, the status and the alarms of the local section of the
LAN
ALL: the keyboard display the value and the status of the local section, but the command given by the
keyboard are effective on all the sections of the LAN. In case of alarm the writing “ASn” is shown, where
“n” is the number of the section in alarm.
SE1…Se5: the keyboard controls from remote the corresponding section (from 1 to 5 depending on LAN
address) of the LAN and display the value of the probes, the who le status and all the alarms of the
section. Only one of this remote control is allowed at the same time.

1. Push the o key for more than 3 seconds

2. The label corresponding to the section controlled by the keyboard will be displayed.

3. With o or n key select the section you want to control.

4. Press “Set” key to confirm and exit

6. REAL TIME CLOCK FUNCTIONS

The following functions are available only if the Real Time Clock is present

6.1 TO SEE THE CURRENT TIME AND DAY

1. Push the n key for more than 3 seconds

2. The following messages are displayed:

Hur (hour); Min (Minute); dAY (day = giorno)

3. To exit push à key or wait 5 seconds

6.2 TO SET THE TIME AND THE WEEKLY HOLIDAYS

1. Push the n key for more than 3 seconds

2. The current time is displayed.

3. By pushing the SET key, sett ing of the current hour, minutes, day and the weekly

holidays (up to 3) will be possible.

4. To exit, press SET + UP or wait 15s without pressing any key.

6.3 TO SET THE DEFROST TIMES

1. Push the n key for more than 3 seconds

2. The current time is displayed.

3. By pushing DEF key, the DEF led will start flashing and set ting defrost time will be

possible.

4. To exit, press SET + UP or wait 15s without pressing any key.

6.4 TO SET THE ENERGY SAVING TIMES

1. Push the n key for more than 3 seconds

2. The current time is displayed.

3. By pushing the ES key, the ES led will start flashing an d sett ing Energy Saving t im e

will be possible.

4. To exit, press SET + UP or wait 15s without pressing any key.

6.5 TO START HOLIDAY FUNCTION BY USING THE KEYBOARD

1. Push the ES key for more than 6 seconds until the label “Hd” is shown.

2. The regulators will follow holiday times.

3. Push the ES key for more than 6 seconds to start normal functioning again.

7. PARAMETER LIST

REGULATION
Hy Differential: (0,1÷25,5°C; 1÷45°F): Intervention differential for set point, always positive. Solenoid

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

LS Minimum set point limit: (-50,0°C

set point.

US Maximu m set point limit: (SET

point.

OdS Outputs activation delay at start up: (0÷255 min) This function is enabled at the init ial start up of

the instrument and inhibits any output activation for the period of time set in the parameter. (AUX
and Light can work)

÷SET; -58°F÷SET) Sets the minimum acceptable value for the

÷110°C; SET÷230°F) Set the maximum acceptable value for set

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