RefPlus Guardian+ RC-C Owner's manual

R
PROGRAMMING
MANUAL
CONDENSER CONTROL
RC-C

2
R
SPECIFICATIONS ................................................................................................................................................................................. 3
REPLACEMENT PARTS ...................................................................................................................................................................... 3
TYPICAL WIRING DIAGRAM ........................................................................................................................................................... 4
OVERALL DIMENSIONS.................................................................................................................................................................... 5
INSTALLATION...................................................................................................................................................................................... 5
INTERFACE KEY DESCRIPTIONS................................................................................................................................................... 6
NAVIGATION PRINCIPLES ....................................................................................................................................................................................... 6
OPERATION PRINCIPLE.................................................................................................................................................................... 7
STATUS AND PROGRAMMING MENU & SUB-MENUS DIAGRAM ................................................................................... 14
MENUS AND PARAMETERS............................................................................................................................................................ 15
VERSION INFO ...................................................................................................................................................................................... 15
STATUS MENU........................................................................................................................................................................................ 15
FACTORY RESET PROCEDURE ........................................................................................................................................................... 19
SETTING UP YOUR CONTROLLER USING THE PROGRAMMING MENU .................................................................................... 21
1. FACTORY SETUP..................................................................................................................................................................................................... 21
SYSTEM SPECIFICATIONS................................................................................................................................................................................... 21
DIGITAL INPUTS.................................................................................................................................................................................................... 30
DELAYS .................................................................................................................................................................................................................. 31
ALARM BUZZERS .................................................................................................................................................................................................. 33
DEVICES RUN HOURS.......................................................................................................................................................................................... 33
ALARMS LOGGING RESET.................................................................................................................................................................................. 34
GENERAL STATUS (NON-ADJUSTABLE) ........................................................................................................................................................... 35
2. USER SETUP............................................................................................................................................................................................................. 36
SETPOINTS............................................................................................................................................................................................................ 37
MAIN PAGE RETURN DELAY............................................................................................................................................................................... 39
3. SERVICE MENU ....................................................................................................................................................................................................... 40
OFFSETS ......................................................................................................................................................................................... 40
BAND AND DYNAMIC “FAN ON”PRESSURE VALUES .................................................................................................................................... 41
4. CLOCK...................................................................................................................................................................................................................... 42
ALARM HISTORY....................................................................................................................................................................................................... 43
ALARM SYSTEM......................................................................................................................................................................................................... 44
SWITCHING THE CONDENSER CONTROL ON/OFF ............................................................................................................. 45
AUXILIARY DISPLAY SETUP............................................................................................................................................................. 46
CONTROLLER INPUTS & OUTPUTS ............................................................................................................................................. 47
Table of ConTenTs
IMPORTANT NOTE:
In this manual and in the controller interface:
• The system that requires the condenser to run is referred to as the REQUIRING UNIT.
• A STAGE is dened as one or more fans controlled simultaneously through a common signal.
• The refrigerant pressure is called R P.
• The outside temperature is called OT.
• Modulating fans refer to ECM variable speed motors (Dynamic fans) or VFD controlled fans.
• ONE-SPEED and TWO-SPEED motors refer to single-speed and twin-speed motors.

3
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speCifiCaTions
ReplaCemenT paRTs
Sensors 1 refrigerant pressure sensor
1 outside temperature sensor
Voltage 208/240/480/575V
Control Voltage 24V (120/240V optional)
Power Input Refer to unit nameplate
Battery Life 10 years (program/data protection)
Operating conditions 14oF to 140oF (-10oC to 60oC), < 90% RH non-condensing
Communication
(optional) Modbus RTU, BACNET MSTP, MODBUS TCP/IP, BACNET IP, SNMP, LonWorks.
Please refer to the Replacement Parts Catalogue available online at www.refplus.com
(https://refplus.com/en/parts-services/)
All RefPlus products have a nameplate with a QR code that you can scan to obtain the unit’s technical pedigree
as well as a list of replacement parts.

4
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TypiCal WiRing DiagRam
#C3
DETAIL "B"
WHITEYELLOW
M#
TB
YELLOW
BLUE
BROWN
RED
ORANGE
V1 BLUE
U2
W2
U1 BLACK
WHITE
BLACK
ORANGE
TB
BLACK
GRAY
W1
V2
RED
RED
TWIN SPEED
WIRING
#C1 #C2
YELLOWWHITE
M#
TB
V1 BLUE
U2
W2
U1
RED
BROWN
ORANGE
YELLOW
BLUE
BLACK
WHITE
BLACK
ORANGE TB
W1
V2
BLACK
GRAY
RED
RED
#L3#L1 #L2#H2 #H3#H1
M4M3
M2M1
M6M5
CONTROL BOX
M8M7
M10M9
M# : Fan Motor
TB# : Motor Thermal Protection
MF# : Motor Fuses
# : Terminal Block
NFD : Non Fused Disconnect
AVV : Air Vent Solenoid Valve
CT# : Control Transformer
(100) : Line number
#L : Low Speed Contactor
#H : High Speed Contactor
#C : Main Contactor
#R : Relay
ATS : Air Temperature Sensor
ATF# : Auto Transformer Fuses
LTS : Liquid Temperature Sensor
ECM WIRING
GND
E1
#R1 #R2
DETAIL "A"
BLACKRED BLUE
24V GND D1 E1 14
L3L2L1
M# 1110V
BLACKRED BLUE
24V GND D1 E1 14
L3L2L1
M# 11 10V
0-10V SUPPLIED FROM
CAREL BOARD (J4)
(200)
(105)
(103)
(100)
(600)
(500) (600)
(100)
(104)
(106) (107) (108)
(100)
(100)
(500)
(500)
(600)
(109)
(10##)
(1051)
(1061) (1071) (1081)
(600)
(500)
REMOTE DISPLAY:
REQUIRED WHEN DISPLAY NOT BUILT INTO THE BOARD
OPTIONAL WHEN DISPLAY BUILT INTO THE BOARD
6 PIN PHONE
CABLE.
50M MAX.
SUPPLIED
BY OTHER
(300) (400)
(300) (400)
CLASS II
(300)
(400)
NO13
NC13
C13
J18
C12
NO12
NC12
J17
NO10
J16
NO11
C9
NO9
C9
NO8
NC8
J15 C8
NO7
J14
C7
NO6
C7
C4
NO5 NO4
J4
J13
C4
NO2
J12
NO3
C1
NO1
J3 C1
RX +
RX -
GRN
J2
J11
G0
J1
G
Serial Cord
RS485
GRN
RX -
RX +
01 02
GENERAL ALARM DRY CONTACT FOR REMOTE INDICATION
ID14
ID10
ID13
J8
IDC13
IDC9 ID12
J7
ID11 ID9
GND
U7 J6
U8 U6
IDC1 ID8 ID7
J5
ID5 ID6 ID4 ID2 ID3 ID1
501
VG0
Y3 Y4 Y2 Y1
VG
GND GND
U5 U4
GND
+VDC
U3 U1
U2
PRESSURE SENSOR
OUTSIDE TEMPERATURE
SENSOR
502
500 SIGNAL 24 V FROM THE REQUIRING UNIT
NOTES: Wires number starting with 1 are BLUE Wires number starting with 2 are are WHITE Wires number starting with 3 are RED Wires number starting with 4 are YELLOW
BLACK
L2
L1
L3
RED
BLUE
USE COPPER SUPPLY WIRES
600/3/60
N.F.D.
3R
2C
GA
CT2
250VA 120
600
3C
1R
4C
TB4
TB6
TB8
TB3
TB5
TB7
DETAIL "C"
100W
T1
CONTROL BOX HEATER
240 600
2R
FP
1A
CC
FS
10A
MDA
FS
1.5A
MDA
5C
TB10TB9
#R#
#L4
#H4
DETAIL "C"
503
500 FAN FAILURE (OPTIONAL) 504 500 CURRENT SENSOR #1 (OPTIONAL) 505 500 CURRENT SENSOR #2 (OPTIONAL) 506 500 CURRENT SENSOR #3 (OPTIONAL) 507 500 CURRENT SENSOR #4 (OPTIONAL) 508
500 CURRENT SENSOR #5 (OPTIONAL)
TWIN SPEED SETUP &
OPTI-MIST ADIABATIC SETUP
CT3
150VA
CT4
250VA
24
600
I1 I2
06
H3
AVV
B1
G
ATS
B2
G
LTS
(TO BE INST'L UNDER
ELECTRICAL BOX)
(TO BE INST'L ON
LIQUID HEADER)
2R1
INTERLOCK M7
M8 M5 M6 M3 M4
MF4
10A CC
MF3
10A CC
MF2
10A CC
M9
M10
MF5
10A CC
M2 M1
H2 H1 H3
X2 X1 X3
ATF1
8A CC
MF1
10A CC
5700VA DETAIL "A"
DETAIL "B"
J10
TO ECM FAN(S) 24
240
CT1 50VA
TO GTO G0
FROM CT1
1GAR1
For reference only. Refer to the wiring diagram supplied with your unit.

5
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oveRall Dimensions
insTallaTion
WARNING: Before installation or maintenance, always check to be sure that main power to system is OFF.
Electrical shock can cause personal injury or death.
SAFETY CONSIDERATIONS
Installing, starting up, and servicing any equipment can be hazardous due to system pressures, electrical components
and equipment location (elevated structures, etc.). Only trained and qualied installers as well as service technicians or
electricians should install, start-up and service this equipment.
When working on the equipment, observe precautions found in the literature, on the tags, stickers, and labels attached to
the equipment.
Follow all safety codes. Wear safety glasses and work gloves.
S: 226mm (8.9”)
M & L: 315mm (12.4”)
S & M:112.2mm (4.4”)
L:1132mm (5.2”)
69.8mm (2.7”)

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inTeRfaCe Key DesCRipTions
ALARM KEY
Lets you access the Alarm menu (some controller models may have a bell icon)
PROGRAMMING KEY
Lets you access the Programming menu (Prg on some controller models)
ESCAPE KEY
Returns to the Status menu or the previous menu (Esc on some controller models)
DOWN KEY
Lets you navigate down through screens and menus or lets you change the value of a eld
UP KEY
Lets you navigate up through screens and menus or lets you change the value of a eld
ENTER KEY
Lets you conrm a selection and lets you navigate between elds in a screen
NAVIGATION PRINCIPLES
1.Use the keys to navigate between screens.
2.Once on the desired screen, use the key to navigate between elds.
3.Once on the desired eld (blinking cursor), you can change the value using the keys.
Note: Press and hold an arrow key to speed up value change.
4.To conrm your selection, press key (note that your selection is conrmed only after is pressed).
WARNING: For certain parameters, which have only two states (ON/OFF, Enable/Disable, Open/Close, etc.), selections will
be applied immediately, without the need to conrm by pressing .
When changing those parameters, the unit may start inadvertently. Always switch the unit off prior to changing any parameter.

7
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opeRaTion pRinCiple
The purpose of a condenser is to condense a gaseous refrigerant into a liquid state through cooling. Regularly, a pressure
sensor sends a pressure reading to the condenser controller to operate fans.
The Guardian+ RC-C Controller monitors the refrigerant pressure in real time and uses predictive smart algorithms to
optimize fan cycling and consequently control the pressure. It can be programmed to run a condenser with up to 20 fans
and can control single-speed, twin-speed or modulating-speed ECM fans.
NOMENCLATURE: in this manual and on the controller screen, the following abbreviations are used:
RP = Refrigerant Pressure
OT = Outside Temperature
P= PSI
B= Bar
oF= Degrees Fahrenheit
oC= Degrees Celsius
CHOICE OF 5 CONTROL METHODS
The controller can run the system using one of the following 5 control methods. It is important for you to understand
these ve methods in order to choose the one that best suits your needs:
Method 1: Fan cycling over a pressure control band. Lower point of the pressure control band set by user.
Method 2: PID (Proportional Integrative Derivative). Pressure setpoint set by the user. Note: This method provides the
smoothest and the most linear ventilation capacity variation while delivering the most precise refrigerant pressure.
Method 3: Fan cycling is driven by an external signal (not supplied by RefPlus). Lower point of the pressure control band
set by user.
Method 4:Fan cycling over a moving pressure control band (variant of method 1). Lower point of the pressure control band
based on outside temperature and on minimum and maximum pressure setpoints set by the user. With this method, the
controller provides a lower refrigerant pressure, when desired, depending on the outside temperature.
Method 5:PID (Proportional Integrative Derivative) (variant of method 2). As in method 2, it offers the same advantages
in airow and precision for refrigerant pressure combined with a pressure setpoint based on outside temperature and
on minimum and maximum pressure setpoints set by the user. Refrigerant pressure control precision + lower refrigerant
pressure if desired.
WHAT IS THE SETPOINT, THE MINIMUM AND MAXIMUM PRESSURE SETTINGS, THE
PRESSURE CONTROL BAND, AND THE LOWER POINT OF THE PRESSURE CONTROL BAND?
In methods 2 and 5 (both PID controlled), the Setpoint is the refrigerant pressure that the controller will try to maintain. The
Setpoint is the result of minimum and maximum pressure settings and the outside temperature.
The Setpoint can either be xed and set by the user or it can be sliding and dependent on the outside temperature (set by the
user). For the setpoint to be xed, set the minimum and the maximum pressure settings to the same value. See graph below.
200 PSI
190 PSI
MAXIMUM PRESSURE SETPOINT
MINIMUM PRESSURE SETPOINT
40F35F 45F 50F 55F
OUTSIDE TEMP.
SETPOINT
Units:PSI/Fahrenheit
Pressure Setpnt Scaler
OutTmp: PressSP
040.0
o
F : 0190.0P
050.0
o
F : 0200.0P
Graph 1: Pressure setpoint depending on outside temperature (methods 2 & 5)

8
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In methods 1, 3 and 4, there is a pressure control range rather than a setpoint, called the pressure control band, within which
the controller will work (fan cycling) to maintain the desired refrigerant pressure. The pressure control band has a lower and
upper point. The lower point of the pressure control band is also the result of minimum and maximum pressure settings and
the outside temperature. The pressure control band range (or length) is set by the user, using the parameter “Band” under
the Service menu. The upper point of the pressure control band is equal to the lower point + Band.
The lower point can either be xed and set by the user or it can be sliding and dependent on the outside temperature (set
by the user). In this last option, the pressure control band will also move to follow changes in the outside temperature, as
shown in Graph 2 below. For the lower point of the pressure control band to be xed, set the minimum and the maximum
pressure settings to the same value.
200 PSI
190 PSI
MAXIMUM LOWER POINT OF
PRESSURE CONTROL BAND
MINIMUM LOWER POINT OF
PRESSURE CONTROL BAND
40F35F 45F 50F 55F
OUTSIDE TEMP.
SETPOINT
Units:PSI/Fahrenheit
Pressure Setpnt Scaler
OutTmp: PressSP
040.0o
F : 0190.0P
050.0o
F : 0200.0P
Graph 2: Lower point of the Pressure control band depending on the outside temperature (methods 1 & 4)
METHODS 1 & 4
There are 3 typical scenarios when operating with method 1 or 4. These are the standard methods with fan cycling over a
pressure control band; xed for method 1 or moving for method 4. These scenarios are for explaination purposes only.
SCENARIO 1:
• Condenser has 20 regular ON/OFF fans (10 stages of 2 fans). Fans can be single or twin speed.
• Lower point of Pressure control band:
Method 1: 200 PSI (set by user).
Method 4: From 190 to 200 PSI based on outside temperature from 40 to 50oF (all set by user). Refer to Graph 2 for
a better understanding.
NOTE: In method 4, the lower point of the pressure control band moves from 190 to 200 PSI. To avoid repeating
similar explanations, this manual will present method 4 with a lower point of pressure control band equal to 200 PSI
(outside temperature equal or above 50oF); so that the explanation is the same for method 1.
• Pressure band set to 100 PSI by user.
• High speed of fans set to 10% by user.
Since the lower point of the pressure control band is 200 PSI and the pressure band is set to 100 PSI, the pressure control
band is from 200 to 300 PSI.
When the condenser is ON but the requiring unit has not yet sent the signal, the condenser remains on stand-by; therefore
no fans are running. Once the signal is sent (refrigeration system is ON), the controller runs the fans according to the
refrigerant pressure (RP).
The software will determine the refrigerant pressure for which each stage will run and stop. The stages are overlapped to
create a bigger gap from ON to OFF points and, consequently, minimize cycling and extend fan life.
In this scenario, the rst stage will start when RP reaches 218.1 PSI and stop when RP drops below 200 PSI. All other
stages will start and stop in a similar way, as shown in Graph 3.
High speed of fans set to 10% implies that when RP rises and reaches the end of the pressure control band + 10% of the
pressure control band, the fans will all run at high speed (only for twin-speed fans). 10% of a 100 PSI pressure control band
= 10 PSI, meaning that at 310 PSI or above, all fans will run at high speed. If RP drops below 300 PSI, they all return to low
speed.

9
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REGULAR
FANS
STAGE ON at OFF
below
ST1 218.1 200
ST2 227.2 209
ST3 236.3 218.1
ST4 245.4 227.2
ST5 254.5 236.3
ST6 263.6 245.4
ST7 272.7 254.5
ST8 281.8 263.6
ST9 290.9 272.7
ST10 299.9 281.8
HS
FAN 310 299.9
STAGE 2
RAMP UP
STAGE 2
RAMP DOWN
STAGE 1
RAMP UP
STAGE 1
RAMP DOWN
STAGE 3
RAMP UP
STAGE 3
RAMP DOWN
STAGE 4
RAMP UP
STAGE 4
RAMP DOWN
STAGE 5
RAMP UP
STAGE 5
RAMP DOWN
STAGE 6
RAMP UP
STAGE 6
RAMP DOWN
STAGE 7
RAMP UP
STAGE 7
RAMP DOWN
STAGE 8
RAMP UP
STAGE 8
RAMP DOWN
STAGE 9
RAMP UP
STAGE 9
RAMP DOWN
STAGE 10
RAMP UP
STAGE 10
RAMP DOWN
218.1200 209 227.2 236.3 245.4 254.5 263.6 272.7 281.8 290.9 299.9 310 320
HIGH-
SPEED
RAMP
DOWN
HIGH-
SPEED
RAMP
UP
PRESSURE CONTROL BAND (SET BY USER) 10% of
pressure
control
band
Lower Point
of Pressure
Control Band
SET BY USER HIGH-SPEED
Upper point
of Pressure
Control Band
Graph 3: Scenario 1 (control methods 1 and 4)
SCENARIO 2:
• Condenser has one stage of dynamic fans (Modulating speed ECM).
• Condenser has 9 stages of regular ON/OFF fans. Fans can be single or twin speed.
• Lower point of pressure control band:
Method 1: 200 PSI (set by user).
Method 4: From 190 to 200 PSI based on outside temperature from 40 to 50oF (all set by user). Refer to Graph 2 for
a better understanding.
NOTE: In method 4, the lower point of the pressure control band moves from 190 to 200 PSI. To avoid repeating
similar explanations, this manual will present method 4 with a lower point of pressure control band equal to 200 PSI
(outside temperature equal or above 50oF); so that the explanation is the same for method 1.
• Pressure band set to 100 PSI by user.
• Modulating fan minimum speed set to 20% and maximum speed to 100% by user.
• High speed of fans set to 10% by user.
Since the lower point of the pressure control band is 200 PSI and the pressure band is set to 100 PSI, the pressure control
band is from 200 to 300 PSI.
When the condenser is ON but the requiring unit has not yet sent the signal, the condenser remains on stand-by; therefore
no fans are running. Once the signal is sent (refrigeration system is ON), the controller runs the fans according to the
refrigerant pressure (RP).
The software will determine the refrigerant pressure for which each stage will run and stop. The stages are overlapped to
create a bigger gap from ON to OFF points and, consequently, minimize cycling and extend fan life.
In this scenario, the modulating fans will start when RP reaches 209 PSI and stop when RP drops below 200 PSI. All other
stages will start and stop in a similar way, as shown in Graph 4.
High speed of fans set to 10% implies that when RP rises and reaches the end of the pressure control band + 10% of the
pressure control band, the fans will all run at high speed (only for twin-speed fans). 10% of a 100 PSI pressure control band
is 10 PSI, meaning that at 310 PSI or above, all fans will run at high speed. If RP drops below 300 PSI, they all return to low
speed.

10
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The modulating fan speed depends on the refrigerant pressure (RP). Below the pressure control band, the modulating
fans will be OFF. When RP increases (RAMP UP), from the lower point of the pressure control band (200 PSI) to the point
where the rst stage of regular fans starts (227.2 PSI), the modulating fan speed increases proportionally from minimum to
maximum speed. However, the modulating fans only start when the pressure reaches a certain level, adjustable by the user
under the Service menu (209 PSI, refer to step 13, page 42). If, after the modulating fans start, the pressure decreases,
the modulating fan speed decreases accordingly to the minimum as shown by the red dotted line (between 209 and 200
PSI); once below 200 PSI, the modulating fans are OFF. If after the modulating fans start, the pressure keeps increasing, the
speed follows the red line between 209 and 227.2 PSI. Once a regular fan stage starts, the modulating fan speed decreases
to the minimum speed and again it increases proportionally from the minimum to the maximum speed from this point to the
point where the next stage of regular fans starts.
The modulating fan speed will also have this behaviour from the point where the last stage of regular fans starts to the point
where the high-speed of regular fans starts (from 299.9 to 310 PSI). Beyond this point, the modulating fan speed increases
proportionally over the next 10 PSI. When RP is decreasing (RAMP DOWN), the behaviour is similar.
See the lines for RAMP UP and RAMP DOWN in Graph 4 below for a better understanding.
NOTE: In case of single-speed fans, the 310 PSI shown in the graph would represent the point where the modulating fans
would be at maximum speed.
MODULATING FANS
(MIN TO MAX)
RAMP UP RAMP DOWN
OFF BELOW 200
ON AT 209 200 - 209
200 - 227.2 209 - 218.1
227.2 - 236.3 218.1 - 227.2
236.3 - 245.4 227.2 - 236.3
245.4 - 254.5 236.3 - 245.4
254.5 - 263.6 245.4 - 254.5
263.6 - 272.7 254.5 - 263.6
272.7 - 281.8 263.6 - 272.7
281.8 - 290.9 272.7 - 281.8
290.9 - 299.9 281.8 - 299.9
299.9 - 310 299.9 - 310
310 - 320 310 - 320
REGULAR FANS
STAGE ON at OFF
below
ST1 227.2 209
ST2 236.3 218.1
ST3 245.4 227.2
ST4 254.5 236.3
ST5 263.6 245.4
ST6 272.7 254.5
ST7 281.8 263.6
ST8 290.9 272.7
ST9 299.9 281.8
HS FAN 310 299.9
STAGE 1
RAMP UP
STAGE 1
RAMP DOWN
STAGE 2
RAMP UP
STAGE 2
RAMP DOWN
STAGE 3
RAMP UP
STAGE 3
RAMP DOWN
STAGE 4
RAMP UP
STAGE 4
RAMP DOWN
STAGE 5
RAMP UP
STAGE 5
RAMP DOWN
STAGE 6
RAMP UP
STAGE 6
RAMP DOWN
STAGE 7
RAMP UP
STAGE 7
RAMP DOWN
STAGE 8
RAMP UP
STAGE 8
RAMP DOWN
STAGE 9
RAMP UP
STAGE 9
RAMP DOWN
HIGH-
SPEED
RAMP
DOWN
HIGH-
SPEED
RAMP
UP
PRESSURE CONTROL BAND (SET BY USER)
HIGH-SPEED
10 PSI
Modulating fan
min to max
Lower point
of pressure control band
Upper point
of pressure control band
218.1200 209 227.2 236.3 245.4 254.5 263.6 272.7 281.8 290.9 299.9 310 320
MODULATING FAN SPEED: 20% (MIN.)
AIR FLOW (RAMP DOWN)
MODULATING FAN SPEED: 100% (MAX.)
AIR FLOW (RAMP UP)
METHOD 1 = SET BY USER
METHOD 4 = BASED ON OUTSIDE TEMP. (REFER TO GRAPH 1)
10% of
pressure
control
band
PSI
Graph 4: Scenario 2 (control methods 1 & 4 with modulating fan)
SCENARIO 3:
• Condenser only has modulating fans (ECM).
• Lower point of pressure control band:
Method 1: 200 PSI (set by user).
Method 4: From 190 to 200 PSI based on outside temperature from 40 to 50oF (all set by user). Refer to Graph 2 for
a better understanding.
NOTE: In method 4, the lower point of the pressure control band moves from 190 to 200 PSI. To avoid repeating
similar explanations, this manual will present method 4 with a lower point of pressure control band equal to 200 PSI
(outside temperature equal or above 50oF); so that the explanation is the same for method 1.