Emerson Copeland XC643 User guide

Application Engineering
B U L L E T I N
AE8-1386 R1 October 2013
Application Guidelines for the
Emerson Closed Loop Digital Controller (XC643)
Table of Contents
Safety
Safety Instructions....................................................2 How to See and Modify the Set Points..................... 11
Safety Icon Explanation............................................2 How to Modify the Set Point of Compressors
Instruction Pertaining to Risk of Electrical Shock, and/or Fans.........................................................12
Fire, or Injury to Persons...........................................3 The Info Menu.........................................................12
Safety Statements ....................................................3 How to Enter the “Pr1” Parameter List .....................12
How to Enter in Parameters List “Pr2” .....................12
Introduction How to Change Parameter Values..........................12
Overview ..................................................................4 Keyboard Locking....................................................13
Product Specifications ..............................................4 Parameters .............................................................13
Components.............................................................5 Compressor Regulation...........................................13
Digital Compressor Regulation................................14
Installation and Controller Operating Instructions Fan Regulation........................................................15
Wiring & Electrical Connections................................6 Use of the Programming "HOT KEY".......................15
Probes Connection...................................................6 Parameter Default Values and Descriptions ............16
Probe Wiring.............................................................6 Commissioning the XC643CX.................................17
Systems with Compressor Pumpdown Cycle............8 Commissioning the XC643 in the E2.....................17-21
Mounting & Installation..............................................8
Controller Display......................................................9
Controller Startup.....................................................10
First Installation......................................................10
How to Set the Kind of Refrigerant.........................10
How to Set the Kind of Probes............................... 11
Programming Procedure........................................ 11
Probe Errors.......................................................... 11
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Safety Instructions
Copeland™compressors are manufactured according to the latest U.S. and European Safety Standards.
Particular emphasis has been placed on the user's safety. Safey icons are explained below and safety
instructions applicable to the products in this bulletin are grouped on page 3. These instructions should
be retained throughout the lifetime of the compressor. You are strongly advised to follow these safety
instructions.
SafetyIconExplanation
DANGER
WARNING
CAUTION
NOTICE
CAUTION
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DANGER indicates a hazardous situation which, if not avoided, will result
in death or serious injury.
WARNING indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION, used with the safety alert symbol, indicates a hazardous
situation which, if not avoided, could result in minor or moderate injury.
NOTICE is used to address practices not related to personal injury.
CAUTION, without the safety alert symbol, is used to address practices
not related to personal injury.
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Instructions Pertaining to Risk of Electrical Shock, Fire, or Injury to Persons
WARNING
WARNING
WARNING
CAUTION
ELECTRICAL SHOCK HAZARD
•Disconnect and lock out power before servicing.
•Discharge all capacitors before servicing.
•Use compressor with grounded system only.
•Molded electrical plug must be used when required.
•Refer to original equipment wiring diagrams.
•
•Failure to follow these warnings could result in serious personal injury.
PRESSURIZED SYSTEM HAZARD
•System contains refrigerant and oil under pressure.
•Remove refrigerant from both the high and low compressor side before
removing compressor.
•
•Never install a system and leave it unattended when it has no charge,
a holding charge, or with the service valves closed without electrically
locking out the system.
•Use only approved refrigerants and refrigeration oils.
•Personal safety equipment must be used.
•Failure to follow these warnings could result in serious personal injury.
BURN HAZARD
•Do not touch the compressor until it has cooled down.
•Ensure that materials and wiring do not touch high temperature areas of
the compressor.
•Use caution when brazing system components.
•Personal safety equipment must be used.
•Failure to follow these warnings could result in serious personal injury or
property damage.
COMPRESSOR HANDLING
•Use the appropriate lifting devices to move compressors.
•Personal safety equipment must be used.
•Failure to follow these warnings could result in personal injury or
property damage.
Safety Statements
•Refrigerant compressors must be employed only for their intended use.
•install, commission and maintain this equipment.
•
•All valid standards and codes for installing, servicing, and maintaining electrical and
refrigeration equipment must be observed.
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INTRODUCTION
The XC643CX is designed to manage one Copeland™
digital compressor on a single-compressor condensing
unit, or two compressors in parallel, with one digital
compressor in addition to a fixed-speed compressor.
The controller also manages condenser fans. Control
is based on the pressure or temperature sensed in the
low pressure suction (compressors) and high pressure
(condenser) circuits.
The front panel offers information on the system status,
the status of loads, and any alarm conditions. The
controller can be easily programmed through a hot key.
The controller can be connected to a monitoring system
via the serial TTL output, using the standard ModBus
RTU protocol.
Overview
On refrigeration applications where the load may vary
over a wide range, some means of capacity control is
often desirable for optimum system performance and
control. In addition, compressor capacity modulation
can reduce power and energy consumption, reduce
Table 1 - Modulation Ranges
Modulation Range
Compressor Family of Full Load
Capacity
Scroll Digital ZBD/ZRD/ZFD/ZPD 10-100%
3D Discus Digital 10-100%
4D Discus Digital 55-100%
6D Discus Digital 70-100%
compressor cycling, and decrease the starting
electrical load. In order to achieve these objectives,
Emerson Climate Technologies has developed the
Copeland Discus Digital™and Copeland Scroll Digital™
compressors.
The XC643 is one module (one part number) which
can support scroll and Discus digital (3D, 4D, 6D)
compressors. See Table 1 for specific modulation
ranges.
For more details on Copeland digital compressors refer
to the following Application Engineering guidelines
or contact your Emerson Climate Technologies
representative:
AE21-1319, Digital Capacity Control for Refrigeration
Scroll Compressors
AE21-1355, Digital Capacity Control for Copeland and
Intelligent Store Discus Refrigeration Compressors
AE4-1357, Upgrade Procedures for Parallel Applications
Using Digital Capacity Control for Copeland and
Intelligent Store Discus Refrigeration Compressors (for
3D Discus)
AE4-1373, Upgrade Procedures for Parallel Applications
Using Digital Capacity Control for Copeland and
Intelligent Store Discus Refrigeration Compressors (for
4D & 6D Discus)
The simplest way to apply the XC643 digital controller
is with one suction pressure transducer or evaporator
temperature sensor. The controller reads the suction
pressure and modulates the digital compressor as
Table 2 - Product Specifications
Housing: Self extinguishing ABS.
Case: Front panel 32x74 mm (1.26x2.91 inch), depth 70mm (2.76 inch)
Mounting: “CX”format panel mounting in a 29x71 mm panel cut-out (1.14x2.80 inch)
Protection: IP20
Frontal protection: IP65
Connections: Removable terminal block 6 and 14 wires
Power supply: 24Vac/dc * 10%, 50-60Hz.
Power absorption: 5VA max
Display: 4 digits red led and 4 digit orange led.
Serial output : TTL standard Communication protocol: ModBus - RTU
Operating temperature: -28 to +60°C (-20 to +140F); Storage temperature: -25-60°C (-13-140F)
Relative humidity: 20-85% (no condensing)
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needed. If condenser fan control is also needed, a
second pressure transducer or condenser temperature
sensor can be added to read the high side pressure at
the exit of the condenser (reading liquid pressure or
liquid temperature).
This digital controller will also work with temperature
sensors rather than pressure transducers. The two
different types of sensors (temperature and pressure)
cannot be mixed. For example, you cannot use a
pressure transducer for suction and a temperature
sensor for condensing in an application.
Pressure transducers and NTC temperature sensors
are available with the controller kit. If you want to use a
different pressure transducer, consult your Application
Engineer.
Table 3 - Components
Part Number
998-0189-00
943-0017-00
929-0005-00
939-0007-00
939-0008-00
939-0009-00
943-0018-00
943-0019-00
962-0007-00
Description
Complete kit with controller, wire harnesses, pressure and NTC temperature
transducers
Controller only
Wire harness only
Pressure transducer only, PP11 suction
Pressure transducer only, PP30 discharge
Temperature transducer only
TTL/ RS485 Serial Converter
Hot key
Optional terminal box
PP11 - PP30 - Bar
7/16”-20UNF
18,5 12,5 17
48
Figure 1 - XC643CX 14 and 6 Pin Connectors
The XC643CX is provided with 2 socket connectors with
14 and 6 pins. These cable harnesses must be used.
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Figure 2 - Standard Pressure Transducer
PP11 -0.5 to 7 bar (-7 to 100 psig) suction, female
PP30 0 to 30 bar (0 to 435 psig) discharge, female
Note: Alternative pressure transducers may be used.
Refer to Table 7.
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TTL/RS485 external converter: used to convert the
TTL output into a RS485 (+) and (-) signal for the
monitoring system MODBUS_RTU compatible.
(XWEB).
Note! When connecting to an E2 System controller for
supervisory control, the polarity from the XC643 should
be reversed from the polarity at the E2 communication
port. The XC643CX uses a 9600 baud rate.
Figure 3 - TTL / RS485 Serial Converter
INSTALLATION AND CONTROLLER OPERATING
INSTRUCTIONS
Wiring and Electrical Connections
Before connecting cables make sure the power supply
complies with the rated voltage requirements. Separate
the probe cables from the power supply cables, the
outputs and the power connections. Do not exceed
the maximum current allowed on each relay (3A
resistive). In case of heavier loads use a suitable
external relay or contactor. Always use a Class 2
transformer with minimum power 5VA.
The power supply for the controller is 19-28VAC,
48-62Hz. The maximum load is 5 VA. 24V power to
the module must be on any time the unit is on and
should not be interrupted by any control. Center tap
transformers are not to be used.
Probes Connection
If using terminal ends be sure there are no bare parts
which could cause short circuiting or introduce noise
disturbance at high frequencies. To minimize the
induced disturbances use shielded cables with the
shield connected to earth.
Pressure probe (4 - 20 mA): respect the polarity.
Pb1 is suction; Pb2 is condenser.
Temperature probe (NTC 10K): Temperature probes
should be insulated from direct air streams to correctly
measure the temperature.
Probe Wiring
The XC643CX is capable of regulating the compressors
and condenser fans on any of the following types of
pressure/temperature sensors. The user must use the
same type of sensor to control the compressors and
the fans.
- 4-20mA pressure transducers (refer to Figure 4a)
- 0.5-4.5V ratiometric pressure transducers (refer
to Figure 4b)
- NTC 10K temperature sensors (refer to Figure 4c)
Note! The 14-pin connector consists of low voltage
wires. Keep the cables away from the power cables.
Use shielded cable to lengthen the cables.
PIN 4 is the common line for the temperature probes PIN
6 gives a 12Vdc supply for the 4-20mA pressure
transducers
PIN 10 is the ground connection for ratiometric pressure
transducers
Digital Line O
Fan2 Fan1 Comp2 Comp ut
15 17 19
16 18 20
Pb1*Pb2*
1 5 7
Hot Key/TTL
2 4 6 8 10
Supply
24V
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12V
40mA
Figure 4 - XC643 Module Connections
6

Pb1
Pb2
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PP11, PP30, 4-20mA pressure transducers
respect the polarity. Pb1 Pb2
dEU= Pr4 5 7
Suction
Brown (+) to terminal 6 ; white (-) to terminal 5 4 6 8
Condenser
12V §
Brown (+) to terminal 6 ; white (-) to terminal 7
40mA
Figure 4a - Wiring Diagram for 4-20 mA Pressure Transducer
Pb1 Pb2
Temperature probes (NTC 10K)
dEU= tPr
Suction: 4-5
Condenser: 4-7
5 7
4 6 8
Figure 4b - Wiring Diagram for NTC 10K Temperature Probes
Ratiometric transducers (0.5 -4.5Vdc)
dEU= Pr5 Gnd
Suction
In In
5 (control); 4(+); 10 (gnd) 1 5 7
Condenser 2 4 6 8 10
7 (control); 4(+); 10 (gnd) + Gnd
5V §
40mA
Figure 4c - Wiring for Ratiometric Pressure Transducers
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•1.5”
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Systems with Compressor Pumpdown Cycle Mounting and Installation
In systems that require a compressor pumpdown,
special attention should be paid to the control logic
for the digital unloader coil. Inherent to the digital
control, the compressor will effectively ramp down and
track the suction pressure by loading and unloading
to decreasing modulation rates. In order to avoid an
extended compressor pumpdown cycle, the digital
solenoid should be wired/controlled such that when a
pump down cycle is initiated the coil is de-energized.
This will force the compressor to run fully loaded (100%
capacity). Refer to AE-1182 and AE-1221 for more
details on pumpdown cycles.
Note: The Digital unloader solenoid is always energized
for 2 seconds upon start-up and at shut down of the
compressor.
PANEL
BRACKET
If this controlleris used outside,it should be enclosed in a
box with IP65 rating. Controllers should be mounted on
panel, in a 29x71 mm (1.14x2.80 inch) hole, and
fixed using the special brackets supplied. The controller
should not be mounted on the compressor nor in the
compressor terminal box.
The ambient operating temperature range is between
14-140 degrees F. (Can operate in ambients as low as
-40°F when applied with an enclosure.)
Ensure ventilation around the controller.
Note! For systems applied in low ambient conditions,
special attention should be paid to the digital
compressor's minimum allowable pressure differential
(Absolute Discharge Pressure - Absolute Suction
Pressure). Copeland Scroll compressors must maintain
at least a 75 PSID while the Copeland Discus must have
a 45 PSID to operate correctly.
(PUSH TO RELEASE)
•3.1”
•Front
•2.6”
•Back
•Side
Figure 5 - XC643 Dimensions and Mounting
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Table 4 - Display Legend
UPPER DISPLAY LOWER DISPLAY ICONS
Suction temperature or Discharge temperature - Active loads
pressure or pressure - Measurement unit
Active Loads Suction
Pressure or
Temperature
Discharge
KPa
Temperature
or Pressure
XC
Figure 6 - Controller Display
Table 5 - Icon Legend
LED FUNCTION MEANING
ON Celsius degrees
ON Fahrenheit degrees
bar ON bar displaying
PSI ON PSI displaying
kPa ON KPA displaying
ON Copeland Scroll Digital compressor on
Digital compressor is waiting to start (flash once per second) or
Flashing digital input alarm for DIGITAL COMPRESSOR (flash twice per
second) or DIGITAL COMPRESSOR in maintenance status.
ON Compressor 2 on
Flashing Compressor 2 is waiting to start (flash once per second)
ON Fan 1 on
Flashing Fan 1 is waiting to start (flash once per second)
ON Fan 2 on
Flashing Fan 2 is waiting to start (flash once per second)
ON The digital solenoid valve coil is energized
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Keyboard
(SET)
Standard view: to see or modify the set point. In programming mode use SETP to
select a parameter or confirm an operation.
(UP)
In programming mode: used to browse the parameter codes or increase the displayed value.
With Hot key inserted: UP starts the Hot key programming procedure.
To access the INFO menu: push and release UP to access the INFO menu.
(DOWN)
In programming mode: used to browse the parameter codes or decrease the displayed value.
Not used Displays running hours for each load Not used
Key Combinations
+ Lock and unlock keyboard
+ Exit programming mode
+ Enter programming mode
Table 6 - Value Pre-Set According to the Kind of Refrigerant
R-404A R-22 R-410A R-507 R-134a R-407A R-407C
SETC (psig) 55 43 78 55 17 42 37
SETF (psig) 220 181 295 220 114 194 179
LSE (psig) 5 1 11 5 -7 -1 -1
HSE (psig) 114 93 155 114 51 99 95
LSF (psig) 170 131 245 169 63 143 130
HSF (psig) 270 231 345 269 163 243 230
Pbd 10 10 10 10 10 10 10
Pb 58 58 58 58 58 58 58
Controller Start-Up
First installation
At first installation:
1. Select the kind of refrigerant.
2. Select the kind of transducer
3. For systems with master controller
supervisory control, set the module node
address.
How to Set the Kind of Refrigerant
The controller has been programmed with several
refrigerants.
The pre-set refrigerant is: R-404A.
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By modifying the refrigerant (FtyP), other defaults will
also change. Refer to Table 6.
If another refrigerant is used:
1. Enter the Programming mode by pressing the
Set and DOWN key for 3s.
2. Select the FtyP, kind of refrigerant,
parameter.
3. Press the “SET”key: the value of the
parameter will start blinking.
4. Use “UP”or “DOWN”to change the refrigerant
among the following:
r22(0) - 134(1) - 404(2) - 407A(3) - 407C(4) -
410(5) - 507(6)
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5. Press “SET”to store the new value and move
to the following parameter.
To exit: Press SET + UP or wait 30s without
pressing a key.
NOTE: the set value is stored even when the
procedure is exited by waiting the time-out to expire.
How to Set the Kind of Probes
1. Enter the programming as described in the
previous parameter
2. Select the dEU kind of probe parameter
according to the following:
a. 4-20mA pressure transducers: dEU = Pr4
b. 0.5-4.5V pressure transducers: dEU = Pr5
c. NTC 10K temperature sensors: dEU = tPr
According to the kind of probe the controller will
display the pressure or the temperature.
Refer to Table 7 for recommended probe settings for
some common pressure transducers.
Programming procedure:
(Example based on changing from default pressure
transducer to Ratiometric Pressure transducer)
1. Hold down the SET and DOWN key for 3
seconds.
2. The controller displays the name of the
parameter in the Lower display, its value on
the Upper display. Select Pr2 and Press “SET”
3. Flashing “0---“is displayed, use the up and
down arrows to set to 3210 and press SET for
each digit.
4. Once the password is entered go to dEU,
press SET, using up and down set to Pr5,
press SET.
5. Set the following parameters PA04, PA20,
FA04, and FA20:
dEU = Pr5
PA04 = Minimum pressure reading on Pb1
PA20 = Maximum pressure reading on Pb1
FA04 = Minimum pressure reading on Pb2
FA20 = Maximum pressure reading on Pb2
Probe Errors
If the display shows a flashing P1 or P2, verify the
probe is wired correctly. If there is a fault on P1, the
Digital compressor will run at 100% loaded. If P2 is
found to be faulty, one fan will be forced on.
A probe error will also be displayed if the probe reads a
value outside the pre-set range.
How to See and Modify the Set Point(s)
How to see the set point of compressors
and/or fans
If the controller is managing both compressors and
fans, both the set points are displayed in sequence,
otherwise only the set point of the enabled section
will be displayed.
1. Push and release the SET key;
2. The Lower display will show the “SEtC”label,
while the Upper display will show its value.
3. To see the fan set point, push again the SET
key.
4. The Lower display will show the “SEtF”label,
while the Upper display will show the fan set
point.
To exit: push the SET key or wait for 30 without
pressing any keys.
Table 7 - Standard Probe Settings
Manufacturer CPC Emerson Flow Controls Dixell
Suction Transducer 800-2200 PT5-07M (802 350) PP11 (939-0007-00)
Discharge Transducer 800-2500 PT5-18M (802 351) PP30 (939-0008-00)
Sensor Type Ratiometric pressure 4-20 mA pressure 4-20 mA pressure
dEU Pr5 Pr4 Pr4
PA04 0 0 -7
PA20 200 100 160
FA04 0 0 0
FA20 500 260 435
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How to Modify the Set Point of Compressors
and/or Fans
NOTICE
Before setting the target set points for the first time,
check and, if necessary, modify the type of refrigerant
(parameter FtyP) and pressure or temperature units.
Refer back to the section titled How to Set the Kind
of Refrigerant.
Procedure
1. Push the SET key for more than 2 seconds;
2. The Lower display will show the “SEtC”label,
the Upper display will show its value flashing.
3. To change the value, push the or
within 30s.
4. To memorize the new value and pass to the
fan set point, push the SET key.
5. The Lower display will show the “SEtF”label,
the Upper display will show the fan set point
flashing.
6. To change its value, push the or
within 30s. Push SET to save and exit.
The INFO Menu
The controller can display important information directly
from the main menu. The INFO menu is accessible by
pushing and releasing the UP key:
NOTE: This information is displayed only if the
related function is enabled
•dStO: percentage of the Pulse Width
Modification output driving the valve of the
digital compressor.
•dSFr: value of temperature or pressure when
the regulation filter of digital compressor is
enabled.
The “regulation filter”function calculates the
average value of the pressure/temperature
during a PWM cycle, and uses this value for
the control algorithm.
To exit: push the SET+UP keys together
How to Enter the “Pr1”Parameter List
To enter the “Pr1”parameter list, user accessible,
operate as follows:
1. Hold pressed the SET and DOWN key for 3s.
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2. The controller displays the name of the
parameter in the Lower display, its value on
the Upper display.
3. Press the “SET”key: the value of the
parameter will start blinking.
4. Use “UP”or “DOWN”to change the value.
5. Press “SET”to store the new value and move
to the following parameter.
To exit: Press SET + UP or wait 30s without
pressing a key.
NOTE: the set value is stored even when the
procedure is exited by waiting for the time-out to
expire.
How to Enter in Parameters List “Pr2”
The “Pr2”parameter list is protected by a security
code (Password).
SECURITY CODE is 3210
To access parameters in "PR2":
1. Enter the “Pr1”level.
2. Select “Pr2”parameter and press the “SET”
key.
3. The flashing value “0 ---”is displayed.
4. Use or to input the security code
and confirm the figure by pressing “SET”key.
5. Repeat operations 2 and 3 for the other digits.
NOTE: Each parameter that can be edited in
“Pr2”can be removed or put into “Pr1”(user level)
by pressing “SET”+ . Additionally, any "Pr1"
parameter can be moved to "Pr2" by pressing "SET"
+ draw down arrow while in the Pr2 list.
How to Change Parameter Values
1. Enter the Programming mode.
2. Select the required parameter with or
3. Press the “SET”key the value start blinking.
4. Use or to change its value.
5. Press “SET”to store the new value and move
to the following parameter.
To exit: Press SET + UP or wait 15s without
pressing a key.
NOTE: the new programming is stored even when
the procedure is exited by waiting the time-out.
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Keyboard Locking
How to Lock the Keyboard
1. Keep the and keys pressed
together for more than 3s.
2. The “POF”message will be displayed and
the keyboard is locked. At this point it is only
possible to view the set point and INFO menu
and enter the parameter list.
To Unlock the Keyboard
Keep the and keys pressed together
for more than 3s till the “POn”flashing
message appears.
Parameters
The XC643CX is pre-set to drive a Copeland Digital
compressor. The relay 15-17 is set to manage the
compressor contactor, while the TRIAC output 17-19
drives the digital solenoid valve.
oA2 (terminal 16-17) output 2 configuration:
Second relay according to the configuration of the
oA2 parameter can work as:
-Compressor: oA2 = cPr,
-Not used: oA2 = nu
oA3 (term. 17-18) output 3 configuration: third
relay according to the configuration of the oA3
parameter can work as:
-Fan: oA3 = FAn,
-Not used: oA3 = nu
oA4 (term. 17-20) output 4 configuration: fourth
relay according to the configuration of the oA4
parameter can work as:
-Fan: oA4 =FAn,
-Not used: oA4 = nu
Compressor Regulation
Pbd: Proportional band or neutral zone width
(0.1-5.0bar/0.5-30°C or 1-150PSI/1-50°F) The
band (or zone) is symmetrical compared to
the target set point, with extremes: set-Pbd/2
- set+Pbd/2. It is used as proportional band
for PI algorithm.
The measurement unit depends on the dEU,
CF, PMU parameters.
inC: Integration time: (0 - 999s) PI integration time
tdS: Digital cycle time: (10-40s) it sets the cycle
time for the digital valve modulation. 15-20
seconds is the recommended Digital cycle time.
20 seconds is the default setting.
don: Time delay between the insertion of second
compressor (0-99.5min; res. 10s).
Triac
0,5A250V
!!!WARNING: Digital unloader
operate at main voltage (230Vac or 115Vac)!!!!
NOTE: Main voltage side (6PINs connector): the PIN
17 is the common line for all the relay outputs and for the
TRIAC.
Triac is internal to the XC643CX controller.
15 16 17 18 19 20
5AMax
DGS
Main voltage DGS Cp2 FAN1 Valve FAN2
230V or 120V
Figure 7 - Relays in XC643
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Digital Compressor Regulation
The pressure is adjusted by a PI regulation.
Pressure
SET + Pbd/2
SET + Pbd/2*(PMA/100)
SET
SET - Pbd/2*(PM/100)
SET - Pbd/2
Time
Triac 100
0 Sut Time
tdS
Compressor
Status
DGS
C1
C2
ton
don Time
toF
doF
Time
Figure 8 - Digital Compressor Regulation
Regulation Start: Increasing Capacity
a. The regulation starts when the suction
pressure (temperature) increases and reaches
the value SET-Pbd/2+(Pbd*10%)/100. At
first, if available, the digital compressor is
powered, and it is modulated in PWM mode.
NOTE: At start up the valve is energized for
two seconds.
b. Within the adjustment range (SET-Pbd/2 ÷
SET+Pbd/2) the digital scroll compressor is
activated in PWM mode in accordance with the
value of the control variable. (NOTE: When the
TRIAC is on, the compressor is unloaded; when
the TRIAC is off, the compressor is loaded).
c. When the pressure is greater than [SET +
Pbd/2] and the TRIAC output is already at
maximum, if applicable, the second compressor is
started after the “don”delay time.
© 2013 Emerson Climate Technologies, Inc.
Printed in the U.S.A.
NOTE: If the Digital compressor is not available due
to pre-set time delays or otherwise, and the pressure
exceeds the value SET +Pbd/2, the fixed compressor
(if available) would be started.
Decreasing Capacity and Regulation Stop
a. When the pressure is lower than [SET - Pbd/2],
the DIGITAL compressor is still modulated to
minimum capacity for 5 seconds.
b. At the end of the 5 seconds the load with more
working hours is shut down. If the load must stay
on because 10 seconds is not over yet, the next
load is considered, and so on until a load that
can be shut down is available.
c. This procedure continues with all active loads,
with the shutdowns spaced out bythe doF time
setting.
d. When only the digital compressor remains on, at
the end of the doF time the digital compressor
is shut down too.
14

Application Engineering
B U L L E T I N
AE8-1386 R1
Limitation of Digital Compressor Capacity
The capacity of the digital compressor can range from
10-100%.
Proportional Band Regulation - Only for Fans
The fan regulation band Pb is divided by the number
of fans:
The numbers of fans switched ON is proportional to the
value of the input signal: when this distances itself from
the target set point and enters the various bands, the
compressors are switched ON, to be then turned OFF
when the signal brings near the set point.
In this way if the pressure is greater than regulation
band, all the fans are on, if the pressure (temperature)
is lower than the regulation band all the fans are off.
Regulation According to the Running Hours
The algorithm switch on and off the loads according to
the running hours of each load. In this way the running
hours are balanced.
Example
2 Fans: oA2 =FAn; oA3 = FAn;
Fan Regulation
Pb Proportional band zone width
(00.10-5.00bar/0.5-30°C or 1-80PSI/1-50°F).
Set the dEU parameter and the target set point for
fans before setting this parameter.
The band is symmetrical compared to the target set
point, with extremes: SETF+Pb/2 - SETF -Pb/2.
The measurement unit depends on the dEU
parameters.
Use of the Programming Hot Key
(Requires Optional Hot Key Programming Kit)
How to Program a Hot Key from the Controller
(UPLOAD)
1. Program one controller with the front keypad.
2. When the controller is ON, insert the Hot Key
and push the key; the "uPL" message
appears followed a by flashing “End”
3. Push “SET”key and the End will stop flashing.
4. Turn OFF the controller remove the Hot Key,
then turn it ON again.
© 2013 Emerson Climate Technologies, Inc.
Printed in the U.S.A.
NOTE: The “Err”message is displayed for
failed programming. In this case push the
key again if you want to restart the upload
again or remove the Hot Key to abort the
operation.
How to Program a Controller using a Hot Key
(DOWNLOAD)
1. Turn OFF the controller.
2. Insert a programmed Hot Key into the 5 PIN
receptacle and then turn the Controller ON.
3. Automatically the parameter list of the Hot Key
is downloaded into the Controller memory,
the “doL”message is blinking followed a by
flashing “End”.
4. After 10 seconds the controller will restart
working with the new parameters.
5. Remove the Hot Key.
NOTE: The message “Err”is displayed for failed
programming. In this case turn the unit off and
then on if you want to restart the download again or
remove the Hot Key to abort the operation.
The unit can UPLOAD or DOWNLOAD the
parameter list from its own internal memory to the
Hot Key and vice-versa.
15

Application Engineering
B U L L E T I N
Parameters - Default Values and Descriptions
Default
AE8-1386 R1
Parameter Value Description Range
SEtC 55 Set point for compressors LSE - HSE
SEtF 220 Set point for fans LSF - HSF
OA2 CPr Load 2 configuration Cpr,Nu
Ptb 1 Parameter table code Readable only
rEL 2.7 Release firmware Readable only
Adr 1 Serial address 1 - 247
oFF no off function enabled no - yES
Pb 58
don 0:30
Proportional band for fan regulation
Time delay between the insertion of
two different loads
(BAR) 0.1-10.0 (°C) 0.1-30.0 (PSI) 1-150 (°F)
1-50 kPa
0 - 99.5 (min.10sec)
tdS 20 Cycle time for digital compressor 10,15,20
inC 300 Integral time 0 - 999 secondi
Pbd 10 Proportional band for compressors
regulation (BAR) 0.1-10.0 (°C) 0.1-30.0 (PSI) 1-150 (°F) 1-50 kPa
PMU PSI Measurement unit for pressure Bar,PSI,Pa
CF °F Measurement unit for temperature °F,°C
dEU Pr4
FCAL 0
FA20 435
FA04 0
Displaying measurement unit:
pressure or temperature
P2 probe offset
20mA or 4.5V readout for P2 probe
4mA or 0.5V readout for P2 probe
tPr(0) - Pr4(1) - Pr5 (2)
(dEU=bar o °C) -12.0 - 12.0(dEU=PSI o °F) -20
- 20
(FA04 - 51.0)BAR (FA04 - 750)PSI (FA04 - 5100)
kPa
(-1.0 - FA20)BAR (-15 - FA20)PSI (-100 - FA20)
kPa
P2C yES P2 probe no - yES
CAL 0
PA20 160
PA04 -7
FtyP 404
P1 probe offset
20mA or 4.5V readout for P1 probe
4mA or 0.5V readout for P1 probe
Freon Type
(dEU=bar or °C) -12.0 - 12.0(dEU=PSI or °F)
-20 - 20; (dEU=kPA) -120 - 120;
(PA04 - 51.0)BAR (PA04 - 750)PSI (PA04 - 5100)
kPa
(-1.0 - PA20)BAR (-15 - PA20)PSI; (-100 - PA20)
kPa
R-404A, R-22, R-410A, R-507, R-134A, R-407A,
R-407C
OA3 FAn Load 3 configuration FAn,Nu
OA4 FAn Load 4 configuration FAn,Nu
LSE 5 Minimum set point (compressors) see Table 6 (depending on refrigerant)
HSE 114 Maximum set point (compressors) see Table 6 (depending on refrigerant)
LSF 170 Minimum set point (fan) see Table 6 (depending on refrigerant)
HSF 270 Maximum set point (fan) see Table 6 (depending on refrigerant)
© 2013 Emerson Climate Technologies, Inc. 16
Printed in the U.S.A.

Application Engineering
B U L L E T I N
AE8-1386 R1
Commissioning the XC643CX
Before connecting the XC643 to the E2, set a unique address for each module. If the module is on the same
network as other devices (CoreSense Protection, XR75CX case display, etc.), Be sure the address is also
unique to those devices. All devices must be on the same baud rate (9600).
To change address in the XC643:
1. Enter the Pr2 menu (password is 3210)
2. Using the UP and DOWN keys select Adr. Press the SET key
3. Change the address (value between 1 - 247) to the desired value using UP/DOWN keys and press
SET to save.
Commissioning the XC643 in the E2
From the main menu, press 7, 7, 2. Go to the C3:ECT tab. Enter the number of XC643 modules that will be
connected to the E2. Press the to back out and save your changes.
© 2013 Emerson Climate Technologies, Inc. 17
Printed in the U.S.A.

Application Engineering
B U L L E T I N
AE8-1386 R1
Commissioning the XC643 in the E2 continued
Press Alt + N to enter the Network Summary screen. Select the module to commission, press F4: Commission.
Enter the address corresponding to the device. Press to save changes.
Press the to access the Main Menu
Select 5. Configured Applications
© 2013 Emerson Climate Technologies, Inc. 18
Printed in the U.S.A.

Application Engineering
B U L L E T I N
AE8-1386 R1
Commissioning the XC643 in the E2 continued
From the Configured Applications menu select 400. XC643CX for the Closed Loop Digital Controller application
Press F5: Setup to enter the Setup screen
Setup Screens
You can modify the Suction and Discharge setpoints
from the C2: Analog tab
© 2013 Emerson Climate Technologies, Inc. 19
Printed in the U.S.A.

Application Engineering
B U L L E T I N
AE8-1386 R1
Setup Screens continued
In the C9: Dgtl Scroll tab, the PI algorithm Press Ctrl + 0 to view additional tabs.
for compressor control can be modified. tDs
corresponds to the Digital Compressor Duty
Cycle.
Additional Tabs
d0n = delay between starts of two different loads
LSE = Low limit of compressor setpoint (SETC)
HSE = High limit of compressor setpoint (SETC)
Pb = Proportional band zone width for fan regulation
LSF = Low limit of fan setpoint (SETF)
HSF = High limit of fan setpoint (SETF)
© 2013 Emerson Climate Technologies, Inc. 20
Printed in the U.S.A.