Emerson XM670 User manual

XM670-XM679 Controllers for
Multiplexed Cabinets Installation and
Operation Manual
026-1218 Rev 4

Emerson Commercial and Residential Solutions
1065 Big Shanty Road NW, Suite 100
Kennesaw, GA 30144 USA
770-425-2724 • 1-800-829-2724
www.emerson.com

Table of Contents • 5
Contents
1 INTRODUCTION.......................................................................................................................................................... 1
1.1. GENERAL WARNING ..................................................................................................................................................... 1
2 OVERVIEW ................................................................................................................................................................... 1
2.1. GENERAL DESCRIPTION................................................................................................................................................ 1
2.2. ORDERING CODES......................................................................................................................................................... 2
3 USER INTERFACE ...................................................................................................................................................... 2
3.1. KEYS AND FUNCTIONS ................................................................................................................................................. 2
3.2. USE OF LEDS............................................................................................................................................................... 3
3.3. HOW TO ENTER THE FAST ACCESS MENU ................................................................................................................... 3
3.4. HOW TO SEE THE MAX AND MIN TEMPERATURE RECORDED ................................................................................... 3
3.5. HOW TO SEE AND MODIFY THE SETPOINT ................................................................................................................... 3
3.6. HOW TO START A MANUAL DEFROST.......................................................................................................................... 3
3.7. HOW TO ENTER THE PARAMETERS LIST PR1 .............................................................................................................. 3
3.8. HOW TO ENTER THE PARAMETERS LIST PR2 .............................................................................................................. 4
3.9. HOW TO ASSIGN A MODBUS ADDRESS ..................................................................................................................... 4
3.10. HOW TO CHANGE THE PARAMETER VALUE............................................................................................................... 4
3.11. ON/OFF FUNCTION .................................................................................................................................................... 4
4 FAST ACCESS MENU ................................................................................................................................................. 5
5 SECTION MENU .......................................................................................................................................................... 6
5.1. TO SET ENERGY SAVING TIMES................................................................................................................................... 6
5.2. TO SET TIMED DEFROST PARAMETERS........................................................................................................................ 6
6 ELECTRONIC EXPANSION VALVE MENU (FOR MODEL XM679 ONLY).................................................... 7
7 CONTROLLING LOADS ............................................................................................................................................ 7
7.1. SOLENOID VALVE ......................................................................................................................................................... 7
7.2. STANDARDS REGULATION AND CONTINUOUS REGULATION ....................................................................................... 7
7.2.1. First Kind of Regulation: Standard Regulation.................................................................................................... 8
7.2.2. Second Kind of Regulation: Continuous Regulation (For Model XM679 Only).................................................. 8
7.3. DEFROST ....................................................................................................................................................................... 8
7.3.1. Defrost starting..................................................................................................................................................... 8
7.3.2. Defrost Ending...................................................................................................................................................... 8
7.4. FANS ............................................................................................................................................................................. 9
7.4.1. Control With Relay................................................................................................................................................ 9
7.4.2. Control With Analog Output (If Present).............................................................................................................. 9
7.5. ANTI-SWEAT HEATERS (IF PRESENT)........................................................................................................................... 9
7.6. AUXILIARY OUTPUT ..................................................................................................................................................... 9
8 PARAMETERS LIST.................................................................................................................................................. 10
9 DIGITAL INPUTS....................................................................................................................................................... 19
9.1. GENERIC ALARM (EAL)............................................................................................................................................. 19
9.2. SERIOUS ALARM MODE (BAL)................................................................................................................................... 19
9.3. PRESSURE SWITCH (PAL) .......................................................................................................................................... 19
9.4. DOOR SWITCH INPUT (DOR) ....................................................................................................................................... 19
9.5. START DEFROST (DEF)............................................................................................................................................... 19
9.6. RELAY AUX ACTUATION (AUS) ................................................................................................................................ 19

6 • XM679K I&O Manual 026-1218 Rev 4
9.7. RELAY LIGHT ACTUATION (LIG) ............................................................................................................................... 19
9.8. REMOTE ON/OFF (ONF) ............................................................................................................................................ 19
9.9. KIND OF ACTION (HTR).............................................................................................................................................. 19
9.10. FHU (NOT USED) ..................................................................................................................................................... 19
9.11. ENERGY SAVING INPUT (ES).................................................................................................................................... 19
9.12. CONFIGURABLE INPUT - HOLIDAY FUNCTION (HDY).............................................................................................. 20
9.13. DIGITAL INPUTS POLARITY....................................................................................................................................... 20
10 INSTALLATION AND MOUNTING...................................................................................................................... 20
11 ELECTRICAL CONNECTIONS............................................................................................................................. 21
11.1. PROBE CONNECTIONS ............................................................................................................................................... 21
12 RS485 SERIAL LINE ................................................................................................................................................ 21
13 HOW TO USE THE HOT KEY ............................................................................................................................... 21
13.1. DOWNLOAD (FROM THE HOTKEY TO THE DEVICE).................................................................................................. 21
13.2. UPLOAD (FROM THE DEVICE TO THE HOTKEY) ....................................................................................................... 22
14 ALARM SIGNALS ................................................................................................................................................... 23
14.1. EE ALARM ................................................................................................................................................................ 24
14.2. ALARM RECOVERY ................................................................................................................................................... 24
15 TECHNICAL DATA ................................................................................................................................................. 25
16 UL RATINGS ............................................................................................................................................................. 26
17 CONNECTIONS ........................................................................................................................................................ 27
17.1. E2 TO XM DEVICE COMMUNICATION RECOMMENDATIONS .................................................................................... 27
17.1.1. Wiring Guidelines ............................................................................................................................................. 27
17.2. XM670 - WIRING DIAGRAM..................................................................................................................................... 27
17.3. XM679 - 230VAC VALVES/WIRING DIAGRAM....................................................................................................... 28
17.4. XM679 - 24VAC VALVES/WIRING DIAGRAM ......................................................................................................... 28
18 E2 MODBUS NETWORK WIRING ....................................................................................................................... 29
19 WIRING LAYOUT FOR SHARING A PRESSURE TRANSDUCER ON A LAN............................................ 30
20 PRESSURE TRANSDUCER SETUP (XM679 ONLY) ......................................................................................... 31
20.1. RS485 NET MONITORING TEMPERATURES ............................................................................................................. 31
20.1.1. RS485 Connection............................................................................................................................................. 31
20.2. HOW TO ENABLE A PRESSURE PROBE TO SHARE ACROSS THE LAN ...................................................................... 32
21 WIRING CONNECTION TO SITE SUPERVISOR.............................................................................................. 33
22 ECT MODBUS NETWORKING TO E2S............................................................................................................... 34
22.1. COM PORT ASSOCIATIONS - E2 VERSIONS 3.XX AND BELOW ................................................................................ 34
22.2. COM PORT ASSOCIATIONS - E2 VERSIONS 4.0 AND ABOVE ................................................................................... 34
22.3. E2 SETUP OF DEVICES .............................................................................................................................................. 35
22.3.1. Set Up Network Ports........................................................................................................................................ 35
22.3.2. Add and Connect the Device............................................................................................................................. 35
22.4. WIRING TYPES .......................................................................................................................................................... 37
22.5. MODBUS TERMINATION BLOCKS ........................................................................................................................... 37
23 DEFAULT SETTING VALUES............................................................................................................................... 38
TABLE 23-1 APPENDIX A - ALTERNATE MODBUS COM WIRING METHOD FOR E2, XR, XM, AND XEV
DEVICES ........................................................................................................................................................................... 45

General Warning Introduction • 1
1 Introduction
1.1. General Warning
Please read the following safety precautions and
warnings before using this manual:
2Overview
2.1. How to Check the
Software Release of the
XM679K
1. Check the software release of the
XM679K printed on the label of the 
controller.
2.2. General Description
Models XM670-XM679 are high level
microprocessor based controllers for multiplexed
cabinets, suitable for applications on medium or low
temperature. It can be inserted in a Local Area
Connection (LAN) of up to eight (8) different sections
that can operate depending on the programming, as
stand alone controllers or by following the commands
coming from the other sections.
XM670/XM679 controllers can have six (6) relay
outputs to control the solenoid valve, defrost that can
be either electrical or hot gas, evaporator fans, lights,
auxiliary output, alarm output and an output to drive
pulsed electronic expansion valves (applicable for
XM679 only).
The controllers can also have up to four (4) probe
inputs: the first one for temperature control, the
second for defrost end temperature control of the
evaporator, the third for the display, and the fourth
probe input can be used for applications with virtual
probe or for inlet/outlet air temperature measurement.
Model XM679 can exclusively have two (2) other
probes that can be used for superheat measurement
and regulation. Both XM670 and XM679 controllers
CAUTION!
• This manual is part of the product and
should be kept near the device for easy and
quick reference.
• The device should not be used for purposes
different from those described in this manual. It
cannot be used as a safety device.
• Check the application limits before proceeding.
SAFETY PRECAUTIONS AND 
WARNINGS!
• Check that the supply voltage is correct
before connecting the device.
• Do not expose to water or moisture: use the
controller only within the operating limits and avoid
sudden temperature changes with high atmospheric
humidity to prevent condensation from forming.
• Warning! Disconnect all electrical connections
before performing any kind of maintenance.
• Fit the probe where it is not accessible by the end
user. The device must not be opened.
• In case of failure or faulty operation, send the
device back to the distributor or to Emerson (see
address) with a detailed description of the fault.
• Verify the maximum current that can be applied
to each relay (see Section 15, 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 main filters in parallel with
inductive loads could be useful.
Figure 2-1 - XM679K Software Release

2 • XM679K I&O Manual 026-1218 Rev 4
are also equipped with three digital inputs (free
contact) that are fully configurable through
parameters.
The Hot Key connector allows simple programming
of the controllers. Direct serial output RS485
MODBUS-RTU compatible permits a simple XWEB
interfacing. Depending on the model, the Hot Key
connector can also be used to connect X-REP display.
2.3. Ordering Codes
Device
Name Description
Emerson
Part
Number
XM670 Solenoid Case Control
115V 318-6520
XM670 Solenoid Case Control
230V 318-6521
XM679 Pulse Case Control
115V 318-6700
XM679 Pulse Case Control
230V 318-6701
Table 2-1 - Product Ordering Codes

Keys and Functions User Interface • 3
3 User Interface
3.1. Keys and Functions
Table 3-1 lists the keys that are found on the front
panel of XM670-XM679 controllers and the function
of each:
Key Function
Press to display the target setpoint, to
select a parameter in programming mode,
or to confirm an operation. Pressing this
key for three (3) seconds while the
minimum or maximum temperature is
displayed will erase the temperature
currently displayed.
Press this key to browse the parameter
codes in programming mode or increases
the displayed value. Pressing this key for
three (3) seconds will give you access to
the Section menu.
Press this key to access the fast access
menu, browse the parameter codes in
programming mode, decrease the
displayed value, or activate or deactivate
an auxiliary output.
Starts a defrost when pressed for three (3)
seconds.
Switches the room light ON and OFF.
Press for three (3) seconds to switch the
device ON and OFF.
Measurement unit
Measurement unit
Measurement unit
Measurement unit
Key Combinations
Locks/Unlocks the keyboard
Switches mode to programming mode
Exits the programming mode
.
3.2. Use of LEDS
LED Mode Function
ON
Compressor and valve regulation
enabled. To see the valve opening
percentage, enter the fast access
menu.
Flashing Anti-short cycle delay enabled
ON Defrost enabled
Flashing Drip time in progress
ON An alarm is occurring
ON Energy saving enabled
ON Fans enabled (fans are running)
Flashing Door opened or delay after defrost
ON Auxiliary relay ON
ON Measurement unit
Flashing Programming phase
ON The controller is working in 
ALL mode
Flashing The controller is working in
remote virtual display mode
Flashing During the CLOCK modification
(if clock is present)
Each LED function is described in Table 3-2:
Figure 3-1 - XM670 - XM679 Front Panel
Table 3-1 - XM670/XM679 Front Panel Keys and Functions Table 3-2 - LEDs
Table 3-1 - XM670/XM679 Front Panel Keys and Functions
(Continued)

4 • XM679K I&O Manual 026-1218 Rev 4
3.3. How to Enter the Fast
Access Menu
1. Press and release the UP button.
2. The First Label will be displayed. Press the UP or
DOWN button to navigate the menu.
3.4. How to See the MAX
and MIN Temperature
Recorded
1. Press and release the UP button.
2. The First Label will be displayed. Press the UP or
DOWN button to navigate the menu. Search the L°t
label and press SET to see minimum temperature;
search the H°t label and press SET to see maximum
temperature.
3.5. How to See and Modify
the Setpoint
1. Press the SET button for three (3) seconds to show
the setpoint value.
2. The measurement unit starts blinking.
3. To change the setpoint value, press the UP or
DOWN button for 10 seconds.
4. To store the new setpoint value, press the SET key
again or wait 10 seconds.
3.6. How to Start a Manual
Defrost
Press the DEF key for more than three
(3) seconds to start a manual defrost.
3.7. How to Enter the
Parameters List PR1
To enter the parameter list in Pr1 (user accessible
parameters):
1. Enter the programming mode by pressing the SET
and DOWN buttons for a few seconds (wait for the
measurement unit to start blinking).
2. The controller will show the first parameter present
in Pr1.
3.8. How to Enter the
Parameters List PR2
To access the parameter list in Pr2:
1. Enter the Pr1 level. Follow the steps in Section 3.7.,
How to Enter the Parameters List PR1.
2. Select Pr2 parameter and press the SET key.
3. The PAS flashing message will display, followed
shortly by “0 --” with a flashing zero.
4. Use the UP or DOWN button to input the security
code in the flashing digit. Confirm the security code
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 way to enter the programming mode is by
pressing the SET and DOWN buttons for 30 seconds
immediately after switching the controller ON.
Figure 3-2 - Parameters List 2
NOTE:Eachparameterin Pr2 can beremoved
or put into Pr1 (user level) by pressing SET +
DOWN buttons. When a parameter is present
in Pr1, the Alarm LED will be display.

How to Assign a MODBUS Address User Interface • 5
3.9. How to Assign a
MODBUS Address
1. To enter the programming mode, press and hold the
SET and DOWN buttons together until the
temperature measurements start blinking.
2. Scroll through the parameters using the UP or
DOWN button until Adr is displayed.
3. Press and hold SET to select Adr.
4. Use the arrow keys to choose the address number of
the device.
5. Press and hold SET again to select the desired
number and save.
6. To exit, press the SET and UP arrow keys together.
3.10.How to Change the
Parameter Value
1. Enter the programming mode.
2. Select the required parameter using the UP or
DOWN button.
3. Press the SET key to display the parameter value
(measurement unit starts blinking).
4. Use the UP or DOWN button to change the value.
5. Press SET to store the new value and move to the
next parameter.
6. To exit, press SET + UP keys or wait 15 seconds
without pressing a key.
3.11.ON/OFF Function
By pressing the ON/OFF key, the
controller shows OFF. During the OFF
status, all the relays are switched OFF
and the regulations are stopped; if a
monitoring system is connected, it does not record the
controller data and alarms.
NOTE: The set value is stored even when the
time-out expires and ends the procedure.
NOTE: During the OFF status, the Light and
AUX buttons are active.

6 • XM679K I&O Manual 026-1218 Rev 4
4 Fast Access Menu
This menu contains the lists probes and some values that are automatically evacuated by the board, such as the
superheat and the percentage of valve opening. The values below stands for:
•nP or noP - probe not present or value not evacuate
•Err - value out of range, probe damaged, not connected or incorrectly configured
FAST ACESS MENU
HM Fast Access Menu to Clock Settings (If present)
An Fast Access to Analog Output
Reading (If present)
SH Superheat Shows the actual superheat value (Only XM679)
oPP Valve opening percentage Shows the actual opening percentage of the valve (Only XM679)
dP1 Probe 1 value displaying Shows the temperature measured by probe 1
dP2 Probe 2 value displaying Shows the temperature measured by probe 2
dP3 Probe 3 value displaying Shows the temperature measured by probe 3
dP4 Probe 4 value displaying Shows the temperature measured by probe 4
dP5 Probe 5 value displaying Shows the temperature measured by probe 5
dP6 Probe 6 value displaying Shows the temperature measured by probe 6
dPP Pressure probe value Shows the value of pressure measured by pressure transducer 
(Only XM679)
rPP Remote pressure probe value Shows the value of pressure received by remote pressure probe
connected to other XM600 device (Only XM679)
L°t Minimum measured temperature Shows the minimum temperature read by the regulation probe
H°t Maximum measured temperature Shows the maximum temperature read by the regulation probe
dPr Virtual regulation probe value Shows the value measured by the virtual regulation probe
dPd Virtual defrost probe value Shows the value measured by the virtual defrost probe
dPF Virtual fans probe value Shows the value measured by virtual fan probe
rSE Real setpoint Shows the setpoint used during the energy saving cycle or during
the continuous cycle
Table 4-1 - Fast Access Menu

To Set Energy Saving Times Section Menu • 7
5 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. Depending on the
programming of this menu, a single keyboard can
control either the module of the local section of the
LAN or ALL. The possibilities are: LOC: the
keyboard controls and display the value, the status,
and the alarms of the local section of the LAN; and
ALL: the command given by the keyboard are
effective on all the sections of the LAN.
1. Press the UP key for more than three (3) seconds.
2. The label corresponding to the section controlled by
the keyboard will be displayed.
3. Using the UP or DOWN key, select the section you
want to control.
4. Press the SET key to confirm and exit.
5.1. To Set Energy Saving
Times
ILE Energy Saving cycle
start during 
workdays
(0 to 23 h 50 min)
During the Energy
Saving cycle, the
setpoint is increased by
the value in HES so
that the operation
setpoint is SET + HES.
dLE Energy Saving cycle
length during 
workdays
(0 to 24 h 00 min) Sets
the duration of the
Energy Saving cycle on
workdays.
ISE Energy Saving cycle
start on holidays
(0 to 23h 50 min)
dSE Energy Saving cycle
length on holidays
(0 o 24h 00 min)
HES Temperature 
increase during the
Energy Saving cycle
(-54 to 54°F/ -30 to
30°C) Sets the
increasing value of the
setpoint during the
Energy Saving cycle.
5.2. To Set Timed Defrost
Parameters
Ld1
to
Ld6
Workday
defrost start
(0 to 23h 50 min) These
parameters set the beginning of
the eight programmable defrost
cycles during workdays. For
example, when Ld2=12.4, the
second defrost starts at 12.40
during workdays.
Sd1
to
Sd6
Holiday 
defrost start
(0 to 23h 50 min) These
parameters set the beginning of
the eight programmable defrost
cycles during holidays. For
example, when Sd2=3.4, the
second defrost starts at 3.40 on
holidays.
Table 5-1 - Energy Saving Times Parameters
Table 5-2 - Timed Defrost Parameters
NOTE: To disable a defrost cycle, set it to nu
(not used). For example, if Ld6=nu, the sixth
defrost cycle is disabled.

8 • XM679K I&O Manual 026-1218 Rev 4
6 Electronic
Expansion Valve
Menu (For Model
XM679 Only)
1. Enter the programming mode by pressing the SET
and DOWN buttons for a few seconds
(measurement unit starts blinking).
2. Press the UP or DOWN key until the controller
displays the EEU label.
3. Press SET. You are now in EEV function menu.
7 Controlling Loads
7.1. Solenoid Valve
The regulation is performed based on the temperature
measured by the thermostat probe that can be a
physical probe or a virtual probe obtained by a
weighted average between the two probes (see
Section 8, Parameters List) with a positive
differential from the setpoint. If the temperature
increases and reaches setpoint plus the differential,
the solenoid valve is opened and then it is closed
when the temperature reaches the setpoint value
again.
In case of fault in the thermostat probe, the opening
and closing time of the solenoid valve are configured
by Con and CoF parameters.
7.2. Standards Regulation
and Continuous
Regulation
The regulation can be performed in two ways:
• Standard regulation is reaching the best superheat
via a classic temperature regulation obtained using
hysteresis.
• Continuous regulation permits the use of the valve
to realize a high performance temperature regulation
with a good factor of superheat precision. This only
can be used only in centralized plants and it is
available only with electronic expansion valve by
selecting the CrE=Yparameter.
In any case, the regulation is performed via the PI
regulator that gives the opening percentage to the
valve via PWM modulation explained as follows:
Opening Percentage is obtained from the average of
the Opening Time with respect to the CyP time period
(see Figure 7-1).

Defrost Controlling Loads • 9
Opening percentage is the percentage of the cycle
period where the valve is open. For example, if
CyP=6s (standard value) and the valve is opened at
50%, this means that the valve is opened for three (3)
seconds during the cycle period.
7.2.1. First Kind of Regulation:
Standard Regulation
In this case, the Hy parameter is the differential for
the standard ON/OFF regulation. In this case, the int
parameter is neglected. The regulation follows the
diagram shown in Figure 7-2:
7.2.2. Second Kind of Regulation:
Continuous Regulation 
(For Model XM679 Only)
In this case, the Hy parameter is the proportional band
of PI in charge of room temperature regulation. It is
advisable to use at least Hy=10°F/ 5.0°C.
The int parameter is the integral time of the same PI
regulator. Increasing the int parameter will cause the
PI regulator to react more slowly, and is true vice
versa. To disable the integral part of regulation, set
int=0.
7.3. Defrost
7.3.1. Defrost starting
In any case, the device checks the temperature that is
read by the configured defrost probe before starting
defrost procedure. After that:
• Starting defrost cycles 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 it will wait until all the
other LAN controllers finish their defrost cycle
before the normal regulation of the temperature is
restarted according to the dEM parameter.
• Every time any of the LAN controllers begin a
defrost cycle, it issues the command to the network
making all the other controllers start their own cycle.
This allows a perfect synchronization of the defrost
in the whole multiplexed cabinet according to LMd
parameter.
• By selecting the dPA and dPb probes and changing
the dtP and ddP parameters, defrost can be started
when the difference between the dPA and dPb
probes is lower than dtP for all ddP time. This is
useful to start defrost when a low thermal exchange
is detected. If ddP=0, this function is disabled.
7.3.2. Defrost Ending
•If dPA and dPb are present and d2P=y, the
controller stops the defrost procedure when dPA is
higher than the dtE temperature and dPb is higher
than the dtS temperature.
At the end of defrost, the drip time is controlled
through the Fdt parameter.
Figure 7-1 - Regulation via PI Regulator
Figure 7-2 - First Kind of Regulation
Figure 7-3 - Second Kind of Regulation

10 • XM679K I&O Manual 026-1218 Rev 4
7.4. Fans
7.4.1. Control With Relay
The fan control mode is selected by means of the FnC
parameter:
•C-n = running with the solenoid valve, OFF during
defrost
•C-y = running with th1e solenoid valve, ON during
defrost
•O-n = continuous mode, OFF during defrost
•O-y = continuous mode, ON during defrost
An additional parameter FSt provides the setting of
temperature, detected by the evaporator probe, above
which the fans are always OFF. This ensures that air
is circulated only if the temperature is lower than set
in FSt.
7.4.2. Control With Analog Output
(If Present)
The modulating output (trA=rEG) works in a
proportional manner (excluding the first AMt
seconds where the fans speed is the maximum). The
regulation setpoint is relative to the regulation
setpoint and is indicated by the parameter ASr, the
proportional band is always located above the
SET+ASr value and its value is PbA. The fans are at
minimum speed (AMi) when the temperature read by
the fan probe is SET+ASr and the fans are at
maximum speed (AMA) when the temperature is
SET+ASr+PbA.
7.5. Anti-Sweat Heaters 
(If Present)
This control is performed when trA=AC. In this case,
there are two ways to control the anti-sweat heaters:
• Without real dewpoint information: in this case, the
default value for dewpoint is used (SdP parameter).
• Dewpoint received from the XWEB5000 system:
the SdP parameter is overwritten when the valid
value for dewpoint is received from XWEB.
The P4 probe is used to perform the regulation and it
should be placed on the showcase glass. In case of P4
error or if P4 is absent, the output is at AMA value for
the AMt time then the output is at 0 value for the time
255-AMt time performing a simple PWM
modulation.
7.6. Auxiliary Output
The auxiliary output is switched ON and OFF by
means of the corresponding digital input or by
pressing and releasing the DOWN key.
Figure 7-4 - Control with Analog Output
Figure 7-5 - Anti-Sweat Heaters

Auxiliary Output Parameters List • 11
8 Parameters List
REGULATION
EEU Access to EEV submenu (only XM679)
Hy
Differential: (1 to 45°F; 0.1 to 25.5°C) This is the intervention differential for setpoint, this value is always
positive. Solenoid valve Cut IN is Setpoint Plus Differential (Hy). Solenoid valve Cut OUT is when the
temperature reaches the setpoint.
Int Integral time for room temperature regulation (Only XM679): (0 to 255 s) This is the integral time for room
temperature PI regulator. 0= no integral action.
CrE Continuous regulation activation (Only XM679): (n to Y) n= standard regulation; Y= continuous regulation.
Use it only in centralized plants.
LS Minimum setpoint limit: (-67°F to SET; -55.0°C to SET) Sets the minimum acceptable value for the setpoint.
US Maximum setpoint limit: (SET to 302°F; SET to 150°C) Set the maximum acceptable value for setpoint.
OdS Outputs activation delay at start up: (0 to 255 min) This function is enabled at the initial start up of the device
and inhibits any output activation for the time set in the parameter. (AUX and Light can work)
AC Anti-short cycle delay: (0 to 60 min) The interval between the solenoid valve stop and the following restart.
CCt
Compressor ON time during continuous cycle: (0.0 to 24.0h; resolution 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 Setpoint for continuous cycle: (-67 to 302°F / -55 to 150°C) it sets the setpoint used during the continuous
cycle.
Con Solenoid valve ON time with faulty probe: (0 to 255 min) The time during which the solenoid valve is active
in case of faulty thermostat probe. With COn=0 solenoid valve is always OFF.
CoF Solenoid valve OFF time with faulty probe: (0 to 255 min) time during which the solenoid valve is off in case
of faulty thermostat probe. With COF=0 solenoid valve is always active.
DISPLAY
CF Temperature measurement unit: °C = Celsius; °F = Fahrenheit. CAUTION! When the measurement unit is
changed the parameters with temperature values have to be checked.
PrU
Pressure mode: (rEL or AbS) defines the mode to use the pressure. CAUTION! the setting of PrU is used for
all the pressure parameters. If PrU = rEL all pressure parameters are in relative pressure unit, if PrU = AbS
all pressure parameters are in absolute pressure unit. (Only XM679)
PMU Pressure measurement unit: (bAr - PSI - MPA) it selects the pressure measurement units. MPA= the value of
pressure measured by kPA*10. (Only XM679)
PMd Way of displaying pressure: (tEM - PrE) it permits showing the value measured by pressure probe with 
tEM= temperature or by PrE= pressure (Only XM679)
rES Resolution (for °C): (in = 1°C; dE = 0.1 °C) allows decimal point display
Lod Device display: (nP; P1; P2, P3, P4, P5, P6, tEr, dEF) it selects which probe is displayed by the device. P1,
P2, P3, P4, P5, P6, tEr= virtual probe for thermostat, dEF= virtual probe for defrost.
Table 8-1 - XM670 to XM679 Parameters List

12 • XM679K I&O Manual 026-1218 Rev 4
red Remote display: (nP; P1; P2, P3, P4, P5, P6, tEr, dEF) it selects which probe is displayed by the X-REP. P1,
P2, P3, P4, P5, P6, tEr= virtual probe for thermostat, dEF= virtual probe for defrost.
dLy Display delay: (0 to 24.0 m; resolution 10s) when the temperature increases, the display is updated of 
1 °F/1°C after this time.
rPA Regulation probe A: (nP; P1; P2, P3, P4, P5) first probe used to regulate room temperature. If rPA = nP the
regulation is performed with real value of rPb.
rPb Regulation probe B: (nP; P1; P2, P3, P4, P5) second probe used to regulate room temperature. If rPb = nP
the regulation is performed with real value of rPA
rPE Regulation virtual probe percentage: (0 to 100%) it defines the percentage of the rPA respect to rPb. The value
used to regulate room temperature is obtained by: value_for_room = (rPA*rPE + rPb*(100-rPE))/100
ELECTRONIC EXPANSION VALVE SUBMENU (Only XM679)
FtY Kind of gas (R22, 134, 404, 407, 410, 507,CO2): Type of gas used by plant. Fundamental parameter for
correct functioning of all system.
SSH Superheat setpoint: [1°F to 45°F] [0.1°C to 25.5°C] This is the value used to regulate superheat.
CyP Cycle Period: (1 to 15s) Allows to set cycle time
Pb Proportional band: (1 to 108°F / 0.1 to 60.0) PI proportional band
rS Band Offset: (-21 to 21°F / -12.0 to 12.0°C) PI band offset
inC Integration time: (0 to 255s) PI integration time
PEO Probe Error opening percentage: (0 to 100%) if a temporary probe error occurs, valve opening percentage is
PEo until PEd time is elapsed.
PEd
Probe Error delay before stopping regulation: (0 to 239 sec. - On = unlimited) if probe error duration is bigger
than PEd then valve totally closes. Pf message displays. If PEd = On valve opening is PEo until probe error
finishes.
OPE Start opening Percentage: (0 to 100%) Valve opening percentage when start function is active. This phase
duration is SFd time.
SFd Start Function duration: (0.0 to 42.0 min: resolution 10s) Sets start function duration and post-defrost
duration. During this phase the alarms are neglected.
OPd Opening Percentage after defrost phase: (0 to 100%) Opening valve percentage when after defrost function
is active. This phase duration is Pdd time.
Pdd Post Defrost Function duration: (0.0 to 42.0 min: resolution 10s) Sets start function duration and post-defrost
duration. During this phase the alarms are neglected.
MnF Maximum opening percentage at normal Functioning: (0 to 100%) during regulation it sets the maximum
valve opening percentage.
dCL Delay before stopping valve regulation: (0 to 255s) When the cooling request goes off, the electronic valve
regulation can go on for the dCL time in order to prevent uncontrolled superheat variation.
Fot
Forced opening percentage: (0 to 100% - nu) it permits to force the valve opening to the specified value. This
value overwrites the value calculated by PID algorithm. CAUTION! To obtain the correct superheat
regulation you have to set Fot = nu.
tPP
Type of Pressure Transducer: (PP - LAn) it sets type of pressure transducer to use: PP= 4 to 20mA pressure
transducer or ratiometric transducer 0 to 5V depending on P5C parameter, LAn= the pressure signal arrives
from another XM600. Referred to Pb5
Table 8-1 - XM670 to XM679 Parameters List

Auxiliary Output Parameters List • 13
PA4 Probe value At 4mA or At 0V: (-1.0 to P20 bar / -14 to PSI / -10 to P20 kPA*10) pressure value measured by
probe at 4mA or at 0V (related to PrM parameter) Referred to Pb5
P20 Probe value 20mA or At 5V: (PA4 to 50.0 bar / 725 psi / 500 kPA*10) pressure value measured by probe at
20mA or at 5V (related to PrM parameter) Referred to Pb5
LPL
Lower Pressure Limit for superheat regulation: (PA4 to P20 bar / psi / kPA*10) when suction pressure comes
down to LPL the regulation is performed with a LPL fixed value for pressure, when pressure comes back to
LPL the normal pressure value is used. (related to PrM parameter)
MOP Maximum Operating Pressure threshold: (PA4 to P20 bar / psi / kPA*10) if suction pressure exceeds
maximum operating pressure value, device signals situation with MOP alarm. (related to PrM parameter)
LOP Lowest Operating Pressure threshold: (PA4 to P20 bar / psi / kPA*10) If the suction pressure comes down to
this value, a low pressure alarm is signaled with LOP alarm. (related to PrM parameter)
dML
delta MOP-LOP: (0 to 100%) When a MOP alarm occurs, the valve will close of the dML percentage every
cycle period until MOP alarm is active. When LOP occurs, the valve will open of the dML percentage every
cycle period until LOP alarm is active.
MSH Maximum Superheat alarm: (LSH to 144°F / LSH to 80.0°C) When the superheat exceeds this value, a high
superheat alarm is signaled after interval SHd.
LSH Lowest Superheat alarm: (0 to MSH °F / 0.0 to MSH °C) When the superheat goes down to this value, a low
superheat alarm is signaled after interval SHd.
SHy Superheat alarm Hysteresis: (1 to 45°F / 0.1 to 25.5°C) Hysteresis for superheat alarm deactivation.
SHd Superheat alarm activation delay: (0.0 to 42.0 min: resolution 10s) When a superheat alarm occurs, the time
SHd have to pass before signaling the alarm.
FrC Fast-recovery Constant: (0 to 100 s) permits to increase integral time when SH is below the setpoint. If FrC=0
fast recovery function is disabled.
DEFROST
dPA defrost Probe A: (nP; P1; P2, P3, P4, P5) first probe used for defrost. If rPA = nP the regulation is performed
with real value of dPb.
dPb defrost Probe B: (nP; P1; P2, P3, P4, P5) second probe used for defrost. If rPB = nP the regulation is
performed with real value of dPA.
dPE defrost virtual probe percentage: (0 to 100%) it defines the percentage of the dPA respect to dPb. The value
used to regulate room temperature is obtained by: value_for_defrost= (dPA*dPE + dPb*(100-dPE))/100.
tdF Defrost type: (EL - in) EL = electrical heater; in = hot gas.
EdF Defrost mode: (in) In= interval defrost activation with idf.
Srt Heater setpoint during defrost: (-67 to 302°F; -55.0 to 150.0°C) if tdF=EL during the defrost the defrost relay
perform an ON/OFF regulation with Srt as setpoint.
Hyr Differential for heater: (1°F to 45°F, 0.1°C to 25.5°C) the differential for heater
tod
Time out for heater: 0 to 255 (min.) if the defrost probe temperature is bigger than Srt for all tod time the
defrost ends although the defrost probe temperature is lower than dtE or dtS. It permits to reduce defrost
duration.
dtP Minimum temperature difference to start defrost: [1°F to 90°F] [0.1°C to 50.0°C] if the difference between
the two defrost probes stays lower than dtP for all ddP time the defrost is activated.
ddP Delay before starting defrost (related to dtP): (0 to 60 min) delay related to dtP.
Table 8-1 - XM670 to XM679 Parameters List

14 • XM679K I&O Manual 026-1218 Rev 4
d2P
Defrost with two probes: (n - Y) n= only the dPA probe is used to defrost management; Y= defrost is managed
with dPA probe and dPb probe. Defrost can performed only if both probe value are lower than dtE for dPA
probe and dtS for dPb probe.
dtE
Defrost termination temperature (Probe A): (-67 to 122°F; -55.0 to 50.0°C) (Enabled only when the
evaporator probe is present) sets the temperature measured by the evaporator probe dPA which causes the
end of defrost.
dtS
Defrost termination temperature (Probe B): (-67 to 122°F; -55.0 to 50.0°C) (Enabled only when the
evaporator probe is present) sets the temperature measured by the evaporator probe dPb which causes the end
of defrost.
IdF Interval between defrosts: (0 to 120h) Determines the time interval between the beginning of two defrost
cycles.
MdF Maximum duration of defrost: (0 to 255 min) When dPA and dPb aren't present, it sets the defrost duration,
otherwise it sets the maximum duration for defrost.
dSd Start defrost delay: (0 to 255 min) This is useful when different defrost start times are necessary to avoid
overloading the plant.
dFd Display during defrost: rt = real temperature; it = temperature reading at the defrost start; Set = setpoint; 
dEF = “dEF” label.
dAd Defrost display time out: (0 to 255 min) Sets the maximum time between the end of defrost and the restarting
of the real room temperature display.
Fdt
Drain down time: (0 to 255 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 to 23.5h) time interval between the end of the fast freezing cycle and
the following defrost related to it.
FAN
FPA Fan probe A: (nP; P1; P2, P3, P4, P5) first probe used for fan. If FPA = nP the regulation is performed with
real value of FPB.
FPB Fan probe B: (nP; P1; P2, P3, P4, P5) second probe used for defrost. If FPB = nP the regulation is performed
with real value of FPB.
FPE Fan virtual probe percentage: (0 to 100%) Defines the percentage of the FPA with respect to FPb. The value
used to regulate room temperature is obtained by: value_for_defrost= (FPA*FPE + FPb*(100-FPE))/100.
FnC
Fan operating mode: 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.
Fnd Fan delay after defrost: (0 to 255 min) The time interval between the defrost end and evaporator fans start.
FCt
Temperature differential avoiding short cycles of fans (0°F to 90°F; 0.0°C to 50.0°C) 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.
FSt Fan stop temperature: (-58 to 230°F; -50 to 110°C) setting of temperature, detected by evaporator probe,
above which the fan is always OFF.
Table 8-1 - XM670 to XM679 Parameters List