Emerson XM678D Specification sheet

XM678D Controllers for Multiplexed
Cabinets with Interior Stepper Driver
Installation and Operation Manual for
Software Release 2.8
026-1219 Rev 3

Emerson
1065 Big Shanty Road NW, Suite 100
Kennesaw, GA 30144
770-425-2724 • www.emerson.com

Table of Contents • v
Table of Contents
1 INTRODUCTION.......................................................................................................................................................... 1
1.1. GENERAL PRECAUTIONS AND WARNINGS.................................................................................................................... 1
2 BEFORE PROCEEDING ............................................................................................................................................. 1
2.1. SOFTWARE RELEASE OF XM678D ............................................................................................................................... 1
3 OVERVIEW ................................................................................................................................................................... 2
3.1. GENERAL DESCRIPTION................................................................................................................................................ 2
3.2. ORDERING CODE .......................................................................................................................................................... 2
4 QUICK REFERENCE GUIDE IN RUNNING THE SELF ADAPTIVE REGULATION .................................... 2
5 INSTALLATION AND MOUNTING ......................................................................................................................... 4
6 WIRING DIAGRAM AND CONNECTIONS ............................................................................................................ 5
6.1. IMPORTANT NOTE......................................................................................................................................................... 5
6.2. WIRING GUIDELINES .................................................................................................................................................... 5
6.3. XM678D WIRING AND CONNECTIONS ........................................................................................................................ 5
6.4. VALVE CONNECTIONS AND CONFIGURATION .............................................................................................................. 6
6.4.1. Types of Cables and Max Length.......................................................................................................................... 6
6.4.2. Valve Selection...................................................................................................................................................... 6
6.4.3. 4-Wire Valves (Bipolar) ........................................................................................................................................ 9
6.4.4. 5- to 6-Wire Valves (Unipolar) ............................................................................................................................. 9
6.5. WIRING CONNECTION OF EMERSON EX3 VALVE ........................................................................................................ 9
6.5.1. Solenoid Valve Connection ................................................................................................................................... 9
6.5.2. EX3 with 24Vac Coil: Transformer Capacity....................................................................................................... 9
6.5.3. Stepper Valve Connection................................................................................................................................... 10
6.5.4. EX3-C230............................................................................................................................................................ 10
6.6. ABSOLUTE MAXIMUM POWER.................................................................................................................................... 10
6.7. KEYBOARD DISPLAY CX660...................................................................................................................................... 11
6.8. LAN CONNECTION ..................................................................................................................................................... 11
6.9. SENSORS FOR SUPERHEAT CONTROL ......................................................................................................................... 11
6.10. HOW TO USE A SINGLE PRESSURE TRANSDUCER ON MULTIPLEXED APPLICATIONS .............................................. 12
6.11. HOW TO CONNECT THE MONITORING SYSTEM ........................................................................................................ 12
6.12. DIGITAL INPUTS........................................................................................................................................................ 13
6.13. ANALOG OUTPUT ..................................................................................................................................................... 13
7 BATTERY BACK UP CONNECTION..................................................................................................................... 14
7.1. XEC SUPERCAP CONNECTION.................................................................................................................................... 14
7.2. EMERSON ECP-024 CONNECTION .............................................................................................................................. 15
8 WIRING LAYOUT FOR SHARING A PRESSURE TRANSDUCER ON A LAN.............................................. 15
9 PRESSURE TRANSDUCER SETUP ........................................................................................................................ 17
9.1. RS485 NET MONITORING TEMPERATURES ................................................................................................................ 17
9.1.1. RS485 Connection............................................................................................................................................... 18
9.2. HOW TO ENABLE A PRESSURE PROBE TO SHARE ACROSS THE LAN ........................................................................ 18
10 WIRING CONNECTION TO SITE SUPERVISOR ............................................................................................. 19
11 USER INTERFACE .................................................................................................................................................. 20

vi • XM678D I&O Manual 026-1219 Rev 3
11.1. DIRECT COMMAND INTERFACE ................................................................................................................................ 20
11.2. ICONS ........................................................................................................................................................................ 20
11.3. KEYBOARD COMMANDS ........................................................................................................................................... 21
11.3.1. Double Commands ........................................................................................................................................... 21
11.4. HOW TO MODIFY THE AIR TEMPERATURE REGULATION SETPOINT ........................................................................ 21
12 HOW TO PROGRAM THE PARAMETERS (PR1 AND PR2) ........................................................................... 22
12.1. HOW TO ENTER PR2 ................................................................................................................................................. 22
12.2. HOW TO MOVE A PARAMETER FROM PR1 TO PR2 LEVEL AND VICE VERSA .......................................................... 22
13 FAST ACCESS MENU.............................................................................................................................................. 23
14 MULTIMASTER FUNCTION MENU (SEC) ........................................................................................................ 24
14.1. SYNCHRONIZED DEFROST......................................................................................................................................... 25
14.1.1. Daily Defrost From RTC: [EdF = rtC] ........................................................................................................... 25
15 COMMISSIONING ................................................................................................................................................... 26
15.1. CLOCK SETTING AND RTC ALARM RESET............................................................................................................... 26
15.2. ELECTRONIC VALVE SETTINGS................................................................................................................................. 26
16 REGULATION FOR SUPERHEAT: SELF ADAPTIVE OR MANUAL OPERATING MODE..................... 27
16.1. PRESSURE FILTERING - SUB PARAMETER................................................................................................................. 27
16.2. GENERAL CONSIDERATIONS ..................................................................................................................................... 27
16.3. MANUAL OPERATING MODE - AMS = NO ............................................................................................................. 27
16.3.1. ON/OFF Temperature Regulation [CrE = n].................................................................................................. 28
16.3.2. Continuous Temperature Regulation [CrE = Y] (With Superheat Regulation) .............................................. 28
16.3.3. Continuous Temperature Regulation [CrE = Y] (Without Superheat Regulation) ......................................... 28
16.4. SELF ADAPTIVE OPERATING MODE - 
AMS = YES ........................................................................................................................................................................ 28
16.5. MINIMUM STABLE SUPERHEAT SEARCH - AMS = YES, ATU = YES..................................................................... 28
16.6. VALVE CAPACITY REDUCING - MNF PARAMETER .................................................................................................. 28
16.6.1. Auto Zero Procedure (Go Home Functions).................................................................................................. 29
17 DISPLAY MESSAGES.............................................................................................................................................. 30
17.1. ALARM RECOVERY ................................................................................................................................................... 31
18 USE OF THE PROGRAMMING HOT KEY ......................................................................................................... 32
18.1. DOWNLOAD (FROM THE HOTKEY TO THE DEVICE).................................................................................................. 32
18.2. UPLOAD (FROM THE DEVICE TO THE HOTKEY) ....................................................................................................... 32
19 CONTROLLING LOADS......................................................................................................................................... 33
19.1. COOLING OUTPUT..................................................................................................................................................... 33
19.2. STANDARD REGULATION AND CONTINUOUS REGULATION ..................................................................................... 33
19.2.1. Standard regulation: [CrE = n]....................................................................................................................... 33
19.2.2. Continuous regulation:

[CrE = Y] ........................................................................................................................................................................ 33
19.2.3. Evaporator valves: [CrE = EUP].................................................................................................................... 33
19.3. DEFROST ................................................................................................................................................................... 33
19.3.1. Defrost starting ................................................................................................................................................ 33
19.3.2. Defrost Ending ................................................................................................................................................. 34
19.4. FANS ......................................................................................................................................................................... 34
19.4.1. Control With Relay........................................................................................................................................... 34
19.4.2. Control With Analog Output (If Present)......................................................................................................... 34
19.5. ANTI-SWEAT HEATERS ............................................................................................................................................. 34

Table of Contents • vii
19.6. AUXILIARY OUTPUT ................................................................................................................................................. 35
20 TECHNICAL DATA ................................................................................................................................................. 36
21 UL RATINGS............................................................................................................................................................. 38
22 E2 MODBUS NETWORK WIRING ....................................................................................................................... 39
23 ECT MODBUS NETWORKING TO E2S .............................................................................................................. 40
23.1. COM PORT ASSOCIATIONS - E2 VERSIONS 4.0 AND ABOVE................................................................................... 40
23.2. E2 SETUP OF DEVICES.............................................................................................................................................. 41
23.2.1. Set Up Network Ports....................................................................................................................................... 41
23.2.2. Add and Connect the Device............................................................................................................................ 41
23.3. WIRING TYPES.......................................................................................................................................................... 42
23.4. MODBUS TERMINATION BLOCKS........................................................................................................................... 43
24 DEFAULT PARAMETER MAP.............................................................................................................................. 44
25 XM678D CONTROLLER ASSOCIATION AND REPLACEMENT PROCEDURE........................................ 61
24.1. OVERVIEW ................................................................................................................................................................ 61
24.2. CASE CIRCUIT OUTPUT CONNECTIONS .................................................................................................................... 61
24.3. DEFROST SYNCHRONIZATION................................................................................................................................... 61
24.4. CASE CIRCUIT INPUT CONNECTIONS........................................................................................................................ 61
24.4.1. Associating the XM678D with Case Control Circuit in E2 ............................................................................. 61
24.4.2. Replacing the XM678D on E2 ......................................................................................................................... 63
APPENDIX A - ALTERNATE MODBUS COM WIRING METHOD FOR E2, XR, XM, AND XEV DEVICES .65

General Precautions and Warnings Introduction • 1
1 Introduction
1.1. General Precautions
and Warnings
Please read the following safety precautions and
warnings before using this manual:
2 Before
Proceeding
2.1. Software Release of
XM678D
1. Look at the software release of XM678D printed on
the label of the controller.
2. If the software release is 2.8, proceed with this
manual; otherwise contact Emerson Retail
Solutions for the correct manual.
WARNING! An isolated transformer for the
XM678D power supply must be used. Do not
share power with any other devices.
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 Retail
Solutions (see address) with a detailed description of
the fault.
• Verify the maximum current that can be applied to
each relay (see Section 20, 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 (our mod. FT1) in parallel with
inductive loads could be useful.
Figure 2-1 - Software Release of XM678D

2 • XM678D I&O Manual 026-1219 Rev 3
3Overview
3.1. General Description
The XM678D controller is a microprocessor based
controller for multiplexed cabinets suitable for
applications on medium or low temperature. It can be
inserted in a proprietary Local Area Network (LAN)
with up to eight (8) different sections that can operate,
depending on the programming, as standalone
controllers or by following the commands coming
from the other sections. The XM678D controller is
provided with six (6) relay outputs to control the
solenoid valve, defrost that can be either electrical or
hot gas, evaporator fans, lights, an auxiliary output
and an alarm output, and with the stepper valve driver.
It also has six (6) probe inputs: for temperature
control, defrost end temperature control, display and
the fourth can be used for application with virtual
probe or for inlet/outlet air temperature measurement.
The fifth and sixth probe inputs are used to evaluate
and control the superheat. The XM678D is also
equipped with three (3) free contact digital inputs that
are fully configurable by parameters.
The Hotkey connector allows simple programming of
the controller. The optional direct serial output RS485
that is MODBUS compatible permits simple XWEB
interfacing. Optionally, an RTC is available.
Depending on the model, the Hotkey connector can
be used to connect the X-REP display.
3.2. Ordering Code
4 Quick Reference
Guide in Running
the Self Adaptive
Regulation
1. After wiring the XM678D; configure the type of
valve, bipolar or unipolar, via tEu (Default 
tEu = bP: bipolar) and tEP (Default tEP =0)
parameters or through the manual settings. See
Section 6.4., Valve Connections and
Configuration for details.
2. Set the proper gas via Fty parameter.
Preset gas is R404A.
Device Name Emerson Code
XM678D 318-6600
Table 3-1 - Product Ordering Code
NOTE: For Alco EX4, EX5, EX6 tEP = 11.
For EX3: tEP = 12
LABEL REFRIGERANT OPERATING
RANGE
R22 r22 -58 to 120°F/
-50 to 60°C
134 r134A -58 to 120°F/
-50 to 60°C
290 r290 - Propane -58 to 120°F/
-50 to 60°C
404 r404A -94 to 120°F/
-70 to 60°C
47A r407A -58 to 120°F/
-50 to 60°C
47C r407C -58 to 120°F/
-50 to 60°C
47F r4107F -58 to 120°F/
-50 to 60°C
410 r410A -58 to 120°F/
-50 to 60°C
448 r448A -69 to 120°F/
-45 to 60°C
Table 4-1 - XM678D Gas Table

Ordering Code Quick Reference Guide in Running the Self Adaptive Regulation • 3
3. Configure the probes:
• Regulation and evaporator probes are preset as
NTC. If another kind of sensors is used, it can
be set to P1c and P2c parameters.
• Superheat evaporator outlet probe is preset as
Pt1000, if another kind of sensor is used, it can
be set to P6c parameter.
• The PP11 (-0.5 to 11 bar) is preset as pressure
probe. It operates at relative pressure (Pru = rE).
If you are using a ratiometric transducer, set
P5c = 0-5. Use parameters PA4 and P20 to set
the range.
4. Set the parameters for self adaptive regulation of
superheat.
•Set CrE = no, this disables the continuous
regulation of the temperature. Default is 
CrE = no.
•Set SSH, superheating setpoint. A value
between 4 and 8 is acceptable. Default is
SSH=8-.
•Set AMS = y, this starts the self adaptive
regulation. Default is AMS = y.
•Set ATU = y, this starts the search of the lowest
stable superheat. Default is ATU = y. This
function reduces the setpoint automatically in
order to optimize the use of the evaporator, and
keeping the superheating regulation stable at
the same time. The minimum allowed SH
setpoint is LSH+2°C.
•Set LSH, low superheating limit. A value
between 2 to 4 is acceptable. Default is 
LSH = 3.
•Set SUb, pressure filter. Default is SUb = 10.
The value can increase up to 20 if the pressure
variation respond too fast.
5. Set the parameters for the temperature regulation.
• Set the temperature setpoint. Default is -5°C.
• Set the differential HY Default is 2°C.
• If the capacity of the valve is higher than
requested, it can be reduced by the parameter.
MNF (default is 100). A proper setting of MnF
will reduce the time that the algorithm takes to
reach the stability. MNF value does not affect
the bandwidth.
449 r449A -69 to 120°F/
-45 to 60°C
450 r450A -69 to 120°F/
-45 to 60°C
507 r507 -94 to 120°F/
-70 to 60°C
513 r513A -69 to 120°F/
-45 to 60°C
CO2 r744 - Co2 -58 to 120°F/
-50 to 60°C
NOTE: Check the pressure gauge reading with
the value of dPP. Press the up arrow once to
enter the Fast Access Menu. If OK, proceed;
otherwise resolve the situation before acting on
parameter.
NOTE: The parameters Pb (regulation band)
and Int (integral time) are automatically
calculated by the controller.
LABEL REFRIGERANT OPERATING
RANGE
Table 4-1 - XM678D Gas Table

4 • XM678D I&O Manual 026-1219 Rev 3
5 Installation and
Mounting
The XM678D controller can function without any
user interface, but normal application is with the
CX660 keyboard.
The CX660 keyboard should be mounted on a vertical
panel, in a 29 x 71 mm hole, and secured using the
special bracket supplied (Figure 5-1).
The temperature range allowed for correct operation
is 0 to 60°C. Avoid places subject to strong
vibrations, corrosive gases, excessive dirt or
humidity. The same recommendations apply to
probes. Allow air to circulate through the cooling
holes.
Figure 5-1 - XM678D Installation and Mounting
Figure 5-2 - XM678D Dimensions

Important Note Wiring Diagram and Connections • 5
6 Wiring Diagram
and Connections
6.1. Important Note
The XM device is supplied with a disconnectable
terminal block to connect cables with a cross-section
of up to 1.6 mm2 for all low voltage connections:
RS485, LAN, probes, digital inputs, and keyboard.
Other inputs, power supply and relay connections are
provided with a screw terminal block or Faston
connection (5.0 mm). Heat-resistant cables have to be
used. Before connecting the cables, verify that the
power supply complies with the controller’s
requirements. Separate the probe cables from the
power supply cables, outputs and power connections.
Do not exceed the maximum current allowed on each
relay. In case of heavier loads, use a suitable external
relay. Maximum current allowed for all loads is 16A.
The probes should 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 measure the average room
temperature correctly. Place the defrost termination
probe among the evaporator fans in the coldest place
(where most ice is formed) and far from heaters or
from the warmest place during defrost to prevent
premature defrost termination.
6.2. Wiring Guidelines
6.3. XM678D Wiring and Connections
DEVICE TYPE RETAIL SOLUTIONS
ANALOG TEMP
SENSOR
DIGITAL INPUT
BELDEN #8761 #22-2
SHIELDED
Retail Solutions P/N 035-0002
RS-485 NETWORK BELDEN #8761 #22-2
SHIELDED
Retail Solutions P/N 035-0002
BELDEN #8641 #24-2
SHIELDED
Retail Solutions P/N 135-8641
PRESSURE
TRANSDUCER
**BELDEN #8771 #22-3
SHIELDED
Retail Solutions P/N 135-8771
**#8771 for alternate 600v
rated wire use BELDEN #8618
16 AWG
*STEPPER VALVE
Use valve manufacturer’s
harness with a maximum length
not to exceed 30 feet (10
meters).
POWER LOADS
AND VALVE
Allow a maximum wire size of
14 AWG (2 mm2).
Table 6-1 - Wiring Guidelines
Figure 6-1 - XM678D Wiring and Connections

6 • XM678D I&O Manual 026-1219 Rev 3
6.4. Valve Connections and Configuration
6.4.1. Types of Cables and Max
Length
To connect the valve to the controller, use only the
shielded cables with section greater than or equal to
0.823 mm2 (AWG18). A twisted shielded cable with
the above specification is suggested. Don’t connect
the shield to the ground, keep it floating. The
maximum distance between an XM controller and a
valve must not exceed 10 meters.
6.4.2. Valve Selection
To avoid possible problems, before connecting the
valve configure the driver by making the right
changes on the parameters.
a. Select the kind of motor (tEU parameter)
b. Check if the valve is present in the tEP parameter
shown in Table 6-2.
*Note that Sporlan has issued new valve setting recommendations for the following valves. Refer to Sporlan 
Bulletin F100-10-4 June 5, 2017 for more information. Sporlan recommends manually entering these settings
(Table 6-3 below) if you have these valve models. Refer to the XM Release Notes P/N 026-4256 for more 
information.
NOTE: In any case, the unique and valid reference has to be considered the data sheet made by valve
manufacturer. Emerson Retail Solutions cannot be considered responsible in case of valve damage due to
incorrect settings.
CAUTION:
1. Configure the driver by making the correct changes on the parameters before connecting the valve. Select
the kind of motor (tEU parameter) and check if the valve is present in the tEP parameter table (Table 6-2).
2. The maximum distance between an XM controller and a valve must not exceed 10 meters. Use only shielded
cables with section greater than or equal to 0.325 mm² (AWG22). A twisted shielded cable with the above specification
is suggested. Don’t connect the shield to any ground, leave it floating.
For valve settings, refer to the manufacturer’s data sheet. The manufacturer will not be responsible for any case
of valve damage due to incorrect valve settings.
Type of
Stepper
Motor
Half/Full
Step -
Kind of
Motor
Movemen
t
Minimum
Numberof
Steps
Maximu
m
Number
of Steps
Current per
Phase
Holding
Current
per Phase
Step Rate
tEP
VALVE MODEL tEU
(bip/unip)
HFS
(Half/full)
LSt
(steps
x10)
USt
(steps
x10)
CPP
(mA x10)
CHd
(mA x10)
Sr
(step/sec)
0 MANUAL SETTINGS Par Par Par Par Par Par Par
1 Danfoss ETS-25/50 bP FUL 7 262 10 10 300
2 Danfoss ETS-100 bP FUL 10 353 10 10 300
3 Danfoss ETS-250/400 bP FUL 11 381 10 10 300
4 *Sporlan SEI 0.5-11 bP FUL 0 159 12 0 200
5 *Sporlan SER 1.5-20 bP FUL 0 159 12 0 200
Table 6-2 - XM678D Stepper Valve and Default Values

Valve Connections and Configuration Wiring Diagram and Connections • 7
If your valve is listed in Table 6-2, select the valve
using the tEP parameter. This way, you can be sure of
the correct configuration.
For connection modes of valves of different
manufacturers, refer to Table 6-4 and Table 6-5.
It is highly recommended that the maximum distance
of the stepper valve harness length between the valve
and the XM678D controller must not exceed 30 feet
(10 meters).
If the valve harness length must be extended beyond
30 feet (10 meters), Emerson Retail Solutions
provides an Inductor Extender (P/N 335-3500) for use
with Sporlan Valves only.
The Inductor Extender (P/N 335-3500) is only for use
with Sporlan Bipolar 4-wire stepper valves with 100
ohm or 75 ohm phase resistance.
When using the Inductor Extender, the XM678D
controller CPP parameter setting must be less than
20; otherwise the Valve, Controller, and/or Inductor
Extender will be damaged or have its life expectancy
drastically shortened.
Refer to Table 6-2 for the list of the XM series
controller supported Sporlan Stepper valves. The
Inductor Extender can only be used with Sporlan
Bipolar Stepper valves that have a setting of 16 or 12
in the CPP column.
The recommended CPP parameter should not be
increased to create AC voltage at the valve, if the
valve harness length is over 30 feet, an Inductor
Extender must be added into the 4-wire valve harness.
When using the Inductor Extender (P/N 335-3500),
any stepper valve harness extensions must not exceed
170 feet total length.
Use 14 AWG wire for valve harness extensions in
conduit. If the valve harness extension is not in
conduit, use 16 AWG or 14 AWG shielded cable with
the shield terminated to an earth grounded chassis.
For valve harness extensions over 100 feet, 14 AWG
shielded cable is recommended.
Using an AC volt meter to measure voltage at the
Valve will not produce accurate results with a voltage
chopper constant current stepper valve drivers as used
in XM678D controllers.
Instead, an AC current meter can be used to measure
valve milliamps as a field verification method.
6 *Sporlan SEI 30 bP FUL 0 319 16 0 200
0*Sporlan SER(I) G,J,K See Table 6-3 below for the recommended Sporlan valve manual settings
8 *Sporlan SEI 50 bP FUL 0 638 12 bP 200
9*SporlanSEH(I)100 bP FUL 0 638 12 bP 200
0*Sporlan SEH(I) 175 See Table 6-3 below for the recommended Sporlan valve manual settings
11 Emerson 
EX4-EX5-EX6
bP FUL 5 75 50 10 500
12 Emerson EX3 uP HAF 2 33 0050
tEP SPORLAN MODEL
Minimum
Number of
Steps
LSt (steps
x10)
Maximum
Number
of Steps
USt (steps
x10)
Current
per Phase
CPP (mA
x10)
Holding
Current
per Phase
CHd (mA
x10)
Step Rate
Sr (steps/
sec)
Extra Steps
During
Closing
Phase
ESt (steps
x10)
Kind of
Motor
Movement
HFS
0 SER-AA, A, B, C, D 0 2507020012FUL
0SERI-F, G, J, K, L
CDS(T)-2, 4, 7 0250 8 0 200 12 FUL
0SEH(I)-175, P, 400, T
CDS(T)-9, 17 0638 8 0 200 32 FUL
Table 6-3 - Recommended Sporlan Valve Manual Settings
Table 6-2 - XM678D Stepper Valve and Default Values

8 • XM678D I&O Manual 026-1219 Rev 3
If the current measurement using the method
described below is less than the recommended value
by more than 20%, the CPP parameter may be
increased by up to 2 (12 to 14 or 16 to 18). The CPP
parameter must be less than 20 when using the
Inductor Extender (P/N 335-3500).
For a CPP parameter of 12, the measured current
should be near 120 mA AC, for a CPP setting of 16,
the measured current should be near 160 mA AC.
Below is a description of using an AC current meter
to test a stepper valve:
Using an AC Volt meter to measure the voltage across
a stepper valve will not produce accurate results if the
valve is driven by a voltage chopper constant current
valve driver. XM678D controllers use a voltage
chopper constant current stepper valve driver.
The stepper valve voltage can be checked by using an
in-line True RMS AC current meter. The AC current
meter will produce a more accurate reading than AC
voltage due to the valve drive switching the voltage to
the valve on and off at a frequency much higher than
a voltmeter can read. The voltage chopper constant
current valve driver maintains a constant AC current
through the valve while the valve is moving, which
makes an AC mA meter ideal to test the valve. The
current can be read in each of the stepper valves two
windings/phases. Due to the fact that current unlike
voltage is the same at any point in a wire, the current
test can be performed at the XM678 controller or at
the valve, and will have the same results. It is no
longer necessary to take apart the case or get on a lift
to access the valve, the in-line current test can be
performed at the most convenient location.
An AC clamp meter will not have enough resolution
to read the stepper valve milliamps.
If the current meter used is not a True RMS meter, the
readings will be approximately10% higher due to the
stepper drive producing square waves and not sine
waves.
1. Power down the XM678D controller.
2. Disconnect the Sporlan valve white wire from the
XM678D controller.
3. Connect the meter red lead from the meter 10A
terminal to the Sporlan valve white wire.
4. Connect the meter black lead from the meter COM
terminal to the XM678D controller where the
Sporlan white wire was removed.
5. Change the meter dial selector to AC amps (~A).
6. Note the mA terminal on the meter. It should be
labeled 400 mA or 300 mA.
7. Power up the XM678D controller.
8. Cycle the valve and verify the meter AC amp
reading is less than 0.3A.
9. If step 8 reading was less than 0.3A, power down
the XM678D controller and move the meter red
lead from the meter 10A terminal to the meter 400
mA or 300mA terminal.
10. If the meter dial selector has an AC mA selection
(~mA), change to the AC mA selection.
11. Power up the XM/678D controller.
12. Cycle the valve and record the maximum constant
meter AC mA reading.
13. The mA reading should be within 20% of the Phase
current CPP setting.
14. The valve voltage can be calculated by multiplying
the mA reading by the valve coil resistance. For
example: 102 mA x 100 ohm valve coil = 10.2V.
150mA x 75 ohm valve coil = 11.25V.
The 2nd valve coil current/voltage can be tested by
repeating the above procedure on the Sporlan valve
Green wire and XM678D controller.
The in-line AC mA meter is also compatible with the
constant voltage stepper valve drivers used in the
MultiFlex ESR, CC100, and CCB.
CAUTION: 0.3A is 300mA; if the AC amp
reading in step 8 was above your meters mA
terminal label: STOP and check. DO NOT
proceed or your meter will be damaged.

Wiring Connection of Emerson EX3 Valve Wiring Diagram and Connections • 9
6.4.3. 4-Wire Valves (Bipolar)
45 BLUE WHITE BLACK
46 BROWN BLACK WHITE
47 BLACK RED RED
48 WHITE GREEN GREEN
6.4.4. 5- to 6-Wire Valves (Unipolar)
45 ORANGE ORANGE
46 RED RED
47 YELLOW YELLOW
48 BLACK BLACK
49 – Common GRAY GRAY
6.5. Wiring Connection of
Emerson EX3 Valve
XM678D and EX3 Connection
The EX3 valve integrates a solenoid valve with
positive shut off on the top and a stepper valve.
6.5.1. Solenoid Valve Connection
a. Verify the coil voltage of solenoid valve and ensure
that it is the same voltage with relay output.
b. Set oA1 or oA6 = E3r (solenoid coil of EX3). Any
other setting of the oA1 or oA6 parameter can
damage the solenoid valve.
c. With oA1 = E3r connect the solenoid valve to the
terminals 11-12.
d. With oA6 = E3r connect the solenoid valve to the
terminals 17-18.
6.5.2. EX3 with 24Vac Coil:
Transformer Capacity
When the coil of the EX3 is at 24Vac and a unique
transformer is used to supply both the controller and
the coil of the valve, a 40VCA transformer must be
used like TF40D. Any transformer with lower
capacity can damage the valve or the controller.
Connection
numbering ALCO EX4/5/6/7/8 SPORLAN SEI-SEH-SER
DANFOSS
ETS
Table 6-4 - 4-Wire Valves (Bipolar)
Connection
numbering SPORLAN SAGINOMIYA
Table 6-5 - 5- to 6-Wire Valves (Unipolar)
NOTE: After making the connection, switch the XM controller OFF and ON to make sure that the valve is
positioned properly.
NOTE: The solenoid coil will be energized
every time the temperature regulation is on and
de-energized when the temperature regulation
is off and during the standby of the controller.

10 • XM678D I&O Manual 026-1219 Rev 3
6.5.3. Stepper Valve Connection
The EX3 unipolar valve has to be connected to the
following terminals listed in Table 6-6.
6.5.4. EX3-C230
E.I connection of EX3 with oA1 = E3r and 230V coil of solenoid valve.
6.6. Absolute Maximum
Power
XM678D is capable of driving a wide range of stepper
valves. Table 6-7 lists the maximum amount of
current that the actuator can supply to the stepper
wiring. The 640-0041 or 640-0040 (24V out, 
20VA min) transformer should be used.
XM678D EX3
Terminal 49 Grey wire
Terminal 48 Blue wire
Terminal 47 Black wire
Terminal 46 Brown wire
Terminal 45 White wire
Table 6-6 - EX3 Unipolar Valve Terminals
Figure 6-2 - EX3-C230 Connection
NOTE: The electrical power absorption of the
valve is not related to the valve’s refrigeration
power. Before using the actuator, please read
the technical manual of the valve supplied by
the manufacturer and check the maximum current
used to drive the valve; verify that the values are lower
than those indicated in Table 6-7.
VALVE
TYPE
BIPOLAR VALVES
(4 wires)
Max Current
0.9A
UNIPOLAR VALVES
(5-6 wires)
Max Current
0.33A
Table 6-7 - Absolute Maximum Power

Keyboard Display CX660 Wiring Diagram and Connections • 11
6.7. Keyboard Display CX660
The XM678D controller can also operate without the
keyboard.
Polarity:
• Terminal [34] [-]
• Terminal [35] [+]
Use twisted shielded cable AWG 18 or less in case of
long distance.
Max Distance: 30m
6.8. LAN Connection
To create a LAN connection and to a perform
synchronized defrost (also called master-slave
functioning):
1. Connect a shielded cable between terminals 38 [-]
and 39 [+] for a maximum of eight (8) sections.
2. The Adr parameter is the number that identifies
each electronic board. Address duplication is not
permitted; in this case, synchronized defrost and the
communication with the monitoring system are not
guaranteed (the Adr is also the MODBUS address).
See Figure 6-4 for an example of a properly
configured LAN connection:
6.9. Sensors for Superheat
Control
Temperature probe: Pb6 Terminals 19-20 without
any polarity.
Select the kind of sensor with the P6C parameter.
Pressure transducer: Pb5 Terminals
[21] = signal input
[22] = power supply for 4 to 20mA transducer
[20] = GND
[23] = +5VDC power supply for ratiometric
pressure transducer
Select the transducer configuration with the P5C
parameter.
Figure 6-3 - XM678D Keyboard Display
Figure 6-4 - LAN Connection
NOTE: If the LAN is connected properly, the
green LED will be ON. If the LAN is not
connected properly, a blinking LED will
display. The maximum allowed distance is
30m.
Figure 6-5 - Sensors for Superheat Control

12 • XM678D I&O Manual 026-1219 Rev 3
6.10.How to Use a Single
Pressure Transducer on
Multiplexed
Applications
A working LAN connection is required (green LED
lit on all XM678D boards of the same LAN). Connect
and configure the pressure transducer only on one
XM678D of the network. Afterwards, the pressure
value read by that single transducer will be used by
each device connected to the same LAN.
To read the pressure value, press the up arrow button
to access the fast selection menu and read the value of
the following parameters:
•dPP - measured pressure (only on the master
device)
•dP5 - temperature value obtained from the pressure
value (temperature conversion)
•rPP - pressure value read from remote location
(only for slave devices)
Examples of error messages:
•dPP = Err -> the local transducer read an incorrect
value; the pressure value is out of range of the
pressure transducer or the P5C parameter is
incorrect. Check if any of the above causes the error,
otherwise replace the transducer.
•rPF -> there is an error in the remote pressure
transducer. Check the status of the board (GREEN
LED); if the LED is OFF, then the LAN is not
functioning, otherwise, check the remote pressure
transducer.
Last Checks about the Superheat:
On the fast access menu:
•dPP - the value read by the gauge.
•dP6 - the value read by the temperature probe, the
temperature of the gas on the evaporator outlet.
•SH - the value of the superheat. The nA or err
message means that the superheat cannot be read at
the moment and the value is not available.
6.11.How to Connect the
Monitoring System
• Connect through terminals 36 [-] and 37 [+].
• Use a shielded twisted cable (for example, Belden
8762 or CAT 5 cable).
• The maximum allowable distance is 1 kilometer.
• Do not connect the shield wire to the earth or ground
terminals of the device. Use insulation tapes to avoid
accidental contacts.
Only one controller for each LAN should be
connected to the RS485 connection.
The Adr parameter is the number that identifies each
electronic board. Address duplication is not
permitted; in this case, synchronized defrost and the
communication with the monitoring system are not
guaranteed (the Adr is also the MODBUS address).
Figure 6-6 - Pressure Transducer on Multiplexed Applications
Figure 6-7 - Connecting the Monitoring System
Figure 6-8 - Connecting Monitoring Systems