dixell XM440K User Manual

Dixell
Installing and Operating Instructions
rel.1.0 –07/03/2002 - cod.
1592013000
1592013000 XM440_460K GB XM440K & XM460K 1/1
XM440K
XM460K
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 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
Models XM440K and XM460K are microprocessor based controllers suitable for applications on
medium or low temperature multiplexed cabinets made of up to 5 units. They can be inserted in a LAN
of up to 5 different sections which can operate, depending on the programming, as stand alone
controllers or following the commands coming from one of the other sections. XM440K is provided with
3 relay outputs to control the solenoid valve, defrost - which can be either electrical or hot gas and the
lights while XM460K is also provided with a relay output to control the evaporator fans. They are also
provided with three NTC probe inputs, one for temperature control, one to control the defrost end
temperature of the evaporator and the third, optional, for the display. There are two digital inputs (free
contact) : one devoted to the Energy saving activation and the other configurable by means of
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 with a
positive differential from the set point: if the temperature increases and reaches set 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 (XM460K)
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”.
4. KEYBOARDS
There are 3 kind of keyboard available for the XM440K and XM460K controller:
T640: 6 Keys, horizontal shape (185x38mm).
V640: 6 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.
Only C443 keyboard
By holding it pressed for 5s set the instrument in Stand By
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.
Only T640 and V640 keyboards
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.
Only C443 keyboard
By holding it pressed for 3s the defrost is started.
Only T640 and V640 keyboards
Switch ON and OFF the instrument.
KEY COMBINATIONS
+
+
To lock and unlock the keyboard.
+
+
To enter the programming mode.
C443: 4 Keys, horizontal shape

dixell XM440K Specifications

General

Brand	dixell
Model	XM440K
Category	Controller
Language	English

Summary

General Warning and Safety

Please Read Before Using This Manual

Essential safety and operational information must be reviewed before using the device.

Safety Precautions

Critical safety guidelines and warnings to prevent hazards and ensure safe operation.

General Description of Controllers

Controlling Loads

Solenoid Valve Operation

Explanation of solenoid valve regulation based on temperature set points and differentials.

Defrost Cycle Management

Description of defrost modes, timing, and synchronization mechanisms.

Evaporator Fan Control (XM460K)

Fan control modes for the XM460K controller, including during defrost cycles.

Keyboard Layouts and Functions

LED Indicator Functions

Meaning of the status lights on the controller interface.

Temperature Monitoring and Reset

How to view and reset recorded minimum and maximum temperatures.

Set Point Adjustment and Manual Defrost

Procedures for modifying the target set point and initiating manual defrost cycles.

Parameter List Access (PR1 & PR2)

Steps to enter and navigate the user-accessible and protected parameter lists.

Parameter Value Modification

Guidance on how to change parameter values and store new settings.

Keyboard Lock and Unlock

Instructions for securing the controller interface by locking the keyboard.

ON/OFF Functionality

How to switch the instrument ON and OFF using specific keyboard functions.

Probe Value Display

Procedure to view the readings from connected temperature probes.

LAN Section Menu Configuration

Real Time Clock and Scheduling

Current Time and Holiday Settings

How to set the current time, day, and up to three weekly holidays.

Defrost Time Configuration

Setting specific times for defrost cycles based on workdays and holidays.

Parameter Reference Guide

Regulation Parameters

Parameters controlling temperature regulation, set points, and differentials.

Display Parameters

Settings for measurement units, resolution, and probe display.

Defrost Parameters

Configuration options for defrost type, mode, termination, and timing.

Fans (XM460K) Parameters

Settings for fan operation mode and delays specific to the XM460K model.

Alarms Parameters

Configuration of temperature and general alarm thresholds and delays.

Probe Inputs Calibration

Adjusting offsets for thermostat, evaporator, and auxiliary probes.

Digital Inputs Configuration

Setting up digital inputs for energy saving, alarms, or defrost activation.

Time and Weekly Holidays Parameters

Parameters for setting specific times for holidays and defrost cycles.

Energy Saving Times Parameters

Configuration of energy saving cycle start and length.

Defrost Times Parameters

Detailed settings for workday and holiday defrost start times.

LAN Configuration Parameters

Parameters for network setup, section addressing, and synchronization.

Other Parameters

Miscellaneous settings not covered in other categories.

Digital Input Functionality

Energy Saving Input Settings

Configuring the digital input for energy saving activation and polarity.

Alarm Input Configurations

Setting up digital inputs for generic and serious alarm modes.

Defrost and Auxiliary Control Inputs

Configuring digital inputs for starting defrost or controlling auxiliary relays.

Remote ON/OFF and Holiday Function Inputs

Setting digital inputs for remote instrument control and holiday mode.

Digital Input Polarity Options

Defining whether digital inputs activate on contact closure or opening.

Installation and Mounting Guidelines

Keyboard Cut-out and Mounting Details

Specific dimensions and procedures for mounting T640, V640, and C443 keyboards.

Electrical Connections

Probe Wiring and Placement Advice

Guidelines for connecting and positioning temperature probes for accurate readings.

RS485 Serial Communication Setup

Programming with the Hot Key

Downloading Parameters from Hot Key

Steps to transfer settings from the Hot Key to the controller.

Uploading Parameters to Hot Key

Steps to transfer settings from the controller to the Hot Key.

Alarm Management and Signals

Local and Remote Alarm Indications

Interpreting alarm messages originating from the local section or LAN.

Alarm Silencing and Relay Behavior

How alarms affect the buzzer and alarm relay output based on configuration.

Specific Alarms and Recovery

Details on 'EE' alarm and procedures for recovering from various alarm states.

Technical Specifications

Connection Schematics

XM440K Wiring Diagram

Schematic showing terminal connections for the XM440K controller.

XM460K Wiring Diagram

Schematic showing terminal connections for the XM460K controller.

Default Settings Reference

Default Regulation Settings

Default values for set point, differential, and probe limits.

Default Display Settings

Default configuration for units, resolution, and probe display.

Default Defrost Settings

Default parameters for defrost type, mode, termination temperature, and interval.

Default Fans Settings (XM460K)

Default fan operating modes and delays for the XM460K.

Default Alarms Settings

Default values for alarm thresholds and delays.

Default Analogue Inputs Settings

Default calibration values for temperature probes.

Default Digital Inputs Settings

Default configurations for digital input functions and polarity.

Default Time and Weekly Holidays Settings

Default times for clock and holiday schedules.

Default Energy Saving Times Settings

Default values for energy saving cycle start and duration.

Default Defrost Times Settings

Default start times for defrost cycles on workdays and holidays.

Default LAN Configuration Settings

Default network parameters for section number, address, and synchronization.

Default Other Settings

Default values for miscellaneous parameters like RS485 address.