AAON RSMD Quick start guide

RSMD
Technical Guide

2RSMD Technical Guide
This manual is available for download from
www.aaon.com/library
www.aaon.com
RSMD TECHNICAL GUIDE REVISION LOG
REVISION AND DATE CHANGE
Rev. F, March 15, 2021 Incorporated RSMD2R di󰀨erentiation information
Rev. G, December 8, 2022 Formatting; errata correction
AAON
2425 South Yukon Ave.
Tulsa, OK 74107-2728
www.aaon.com
Factory Technical Support Phone: [phone]
AAON® Controls Support: 866-918-1100
It is the intent of AAON®to provide accurate and current product
information. However, in the interest of product improvement, AAON®
reserves the right to change pricing, specications, and/or design of its
product without notice, obligation, or liability.
AAON® is a registered trademark of AAON, Inc., Tulsa, OK. BACnet®is a
registered trademark of ASHRAE Inc., Atlanta, GA. Copeland Scroll™ is
a registered trademark of Emerson Electric Co., Saint Louis, MO.
AAON Part Number: G039810, Rev. G
Copyright December 2022 AAON, Inc.
AAON® assumes no responsibility for errors or omissions in this
document. This document is subject to change without notice.
PRODUCT NAME PARTS REFERENCE
PART DESCRIPTION PART NUMBER
Refrigerant System Module for Digital Compressors ( RSMD) ASM02201
VCCX2 Controller ASM01698
Prism 2 ASM02533
IP Module Kit ASM01902
CommLink 5 ASM01874
EBC E-BUS Cable Assembly E-BUS Power & Comm
1.5 ft., 3 ft., 10 ft., 25 ft., 50 ft., 75 ft.,
100 ft., 150 ft., 250 ft., and 1000 ft. spool
G029440 (1.5 ft.), G012870 (3 ft.), G029460 (10 ft.), G045270 (25 ft.),
G029510 (50 ft.), G029530 (75 ft.), G029450 (100 ft.), G029470 (150 ft.),
V36590 (250 ft.), G018870 (1000 ft. spool)
Modular Service Tool SD - Operator Interface ASM01895

3RSMD Technical Guide
OVERVIEW ......................................................................................................................................................... 5
Overview ................................................................................................................................................................. 5
Dimensions ............................................................................................................................................................. 6
WIRING ............................................................................................................................................................... 7
Electrical and Environmental Requirements ........................................................................................................... 7
Inputs Wiring ........................................................................................................................................................... 8
Outputs Wiring ........................................................................................................................................................ 9
INPUTS AND OUTPUTS ................................................................................................................................. 10
Inputs/Outputs Map............................................................................................................................................... 10
Inputs and Outputs.................................................................................................................................................11
SEQUENCE OF OPERATIONS ...................................................................................................................... 12
Cooling Mode, Dehumidication, and Head Pressure Control.............................................................................. 12
LCD SCREENS ................................................................................................................................................ 13
LCD Display Screen and Navigation Keys............................................................................................................ 13
Screens Map......................................................................................................................................................... 14
Screen Descriptions.............................................................................................................................................. 15
Protected Screen Map .......................................................................................................................................... 19
Protected Screen Descriptions ............................................................................................................................. 20
TROUBLESHOOTING ..................................................................................................................................... 23
LED Diagnostics ................................................................................................................................................... 23
Suction Pressure Transducer Testing ................................................................................................................... 24
Copeland Discharge Thermistor Temperature Sensor Testing ............................................................................. 25
Temperature Sensor Testing ................................................................................................................................. 26
Head Pressure Transducer ................................................................................................................................... 27
APPENDIX A: CONDENSER OPTIONS ........................................................................................................ 28
Condenser Congurations .................................................................................................................................... 28
Module Congurations .......................................................................................................................................... 34
TABLE OF CONTENTS

4RSMD Technical Guide
TABLE OF CONTENTS
FIGURES
Figure 1: RSMD Dimensions .................................................................................................................................................. 6
Figure 2: RSMD Inputs Wiring................................................................................................................................................. 8
Figure 3: RSMD Outputs Wiring.............................................................................................................................................. 9
Figure 4: LCD Display and Navigation Keys....................................................................................................................... 13
Figure 5: RSMD LED Locations ............................................................................................................................................ 23
Figure 6: Default Two Condenser Operations..................................................................................................................... 28
Figure 7: Single Condenser per Module Wiring.................................................................................................................. 29
Figure 8: Single Condenser per Two Modules Wiring ....................................................................................................... 30
Figure 9: Single Condenser for Three Modules Wiring ..................................................................................................... 31
Figure 10: A1/B1 Condenser Wiring....................................................................................................................................... 32
Figure 11: A2/B2 Condenser Wiring....................................................................................................................................... 33
TABLES
Table 1: Electrical and Environmental Requirements..........................................................................................................7
Table 2: RSMD Inputs and Outputs......................................................................................................................................10
Table 3: Navigation Key Functions.......................................................................................................................................13
Table 4: Main Screens............................................................................................................................................................15
Table 5: Module Screens .......................................................................................................................................................15
Table 6: System Status Screens...........................................................................................................................................16
Table 7: Sensor Status Screens ...........................................................................................................................................16
Table 8: Alarms Screens ........................................................................................................................................................17
Table 9: Alarm History Screens.............................................................................................................................................18
Table 10: Setpoint Status Screens .........................................................................................................................................18
Table 11: Conguration Screens.............................................................................................................................................20
Table 12: Diagnostic Screens..................................................................................................................................................21
Table 13: Suction Pressure Transducer Chart for R410-A Refrigerant.............................................................................24
Table 14: Discharge Thermistor Temperature and Resistance..........................................................................................25
Table 15: Type III 10 K Ohm Thermistor Sensor Temperature and Resistance ..............................................................26
Table 16: Head Pressure Transducer Chart.......................................................................................................................... 27

5RSMD Technical Guide
OVERVIEW
Overview
Features and Applications
The Refrigerant System Module for Digital Compressors (RSMD)
can monitor and control up to two compressors and condensers. The
compressors can be in either a tandem or non-tandem conguration.
The module is designed for R410-A refrigerant.
The RSMD is for units that match all of the following criteria:
• One or two circuits;
• Compressors may be any mix of xed, two-step, and
digital;
• Reheat is present on the rst circuit.
The RSMD is connected to the VCCX2 Controller. Up to four
RSMD Modules can be connected, depending on the size of the
system. There are two E-BUS expansion ports which allow the use
of communicating sensors and E-BUS modules.
The RSMD provides three analog inputs, four binary inputs, ve
relays, and two analog outputs. See Figure 2, page 8, and Figure
3, page 9, for wiring.
The RSMD Module provides the following:
• Modulates the compressors to satisfy the Suction Coil
(Saturated) Temperature. The Suction Coil (Saturated)
Temperature Setpoint is reset by the VCCX2 Controller
to maintain the Supply Air Temperature during Cooling
Mode. During Dehumidication Mode, it controls the
compressors to directly maintain the Suction (Saturated)
Temperature Setpoint.
• When the Heat Pump is in Heating Mode, the RSMD
modulates and stages the compressors to maintain a given
Supply Air Temperature Setpoint.
• Modulates the condenser fans or valves to maintain the
Head Pressure Setpoint.
• Provides alarms and safeties for the compressor and
condenser operation.
• Connects to the Modular Service Tool SD when the
communication wire is run to the VCCX2 Controller.
• Provides a 2 x 8 LCD character display and four buttons
that show status, setpoints, congurations, sensors, and
alarms. Also allows user to change the module’s address,
if necessary.

6RSMD Technical Guide
OVERVIEW
Dimensions
Figure 1: RSMD Dimensions
6.15
3.09
3.07
4.96
5.26
5.55
0.75 4.10 0.74
5.05
GND
TEMP3
TEMP2
TEMP1
TB9
GND +5V
D12
BIN4
D11
BIN3
D10
BIN2
D9
BIN1
TB12
GND
HP-2
+5V
TB8
GND
J1 C
C
SP-2
+5V
TB6
GND
HP-1
+5V
TB3 POWER
COMM
ALARM
STATU
GND
SP-1
+5V
TB4
YS102632 REV 1
R30 4751
R1
R34 4751
R2
4751 R38
R3
4751 R42
R4
4751 R58
R5
COM
V6
TB7
COMP1
24VAC
P6
COMP2
TB11
AOUT 1
AOUT 2
GND
P2
HH485
R+
GND
T-
TB2
C20
.01uF
I
O
I
O
OMRON
G5Q-1A4
DC12V
SA
5A30VDC
CHINA 10A250VAC~
R14
R27
R28 R31
R32 R35
R36 R39
R40 R44
R43
C43
R49
R48
R56
R54
1002
1002
1002
1002
1002
1002
.1uF
1002
1002
.1uF
1002
1002
.1uF
1002
1002
.1uF
1002
1002
.1uF
1002
1002
SERIAL #
ALARM
UP
DOWN
ENTERMENU
AAON P/N:ASM02201
+24 VAC
GND
RELAY CONTACT
RATING IS 1 AMP
MAX @ 24 VAC
CONDENSER 1
COMP 1
COMP 2
ANALOG OUT
REVERSING VALV E
COMMON
RELAY OUTPUT
TERMINALS
LABEL P/N:
G041660
COND 1
COND 2
GND
24 VAC
POWER ONLY
WARNING!
POLARITY
MUST BE
OBSERVED
OR THE
CONTROLLER
WILL BE
DAMAGED
CONDENSER 2
HEAD PRES 1
+5 V
+5 V
COMP DIS 1
COMP 1
SP-1
HP-1
COMP DIS 2
COMP 2
GND
GND
OA COIL/POWF
EMER SHDN
GND
LEAVING H20
GND
SUCTION PRES 2
HEAD PRES 2
+5 V
+5 V
SP-2
HP-2
GND
GND
R+
SHD
T-
R+ SHD T-
E-BUS DUAL E-BUS
EXPANSION
RSM FOR DIGITAL COMPRESSORS
www.aaon.com
SUCTION PRES 1
NOTE: All dimensions are in inches.

7RSMD Technical Guide
WIRING
Electrical and Environmental Requirements
General
Correct wiring of the AAON unit controller and its modules is
the most important factor in the overall success of the installation
process. TheAAON unit controller and modules are factory installed
and wired at the AAON factory. Some of the following information
may not apply if unit was pre-wired at the factory. However, if
troubleshooting of the controller or modules is required, it is a good
idea to be familiar with the system wiring.
Wiring
The modules must be connected to an 18-30 VAC power source
of the proper size for the calculated VA load requirements. All
transformer sizing should be based on the VA ratings listed in Table
1, this page.
ELECTRICAL AND ENVIRONMENTAL
REQUIREMENTS
Control
Device
Voltage
VA Load
Operating
Temperature
Humidity
(Non-
Condensing)
RSMD
Module
18-30 VAC 18 -4°F to 158°F
(-20ºC to 70ºC) 0-95% RH
Inputs
Resistive Inputs require 10KΩ
Type 3 Thermistor
24VAC Inputs provide 4.7kΩ Load
Outputs Relay Outputs: 1 Amp
maximum per output.
Table 1: Electrical and Environmental Requirements
NOTE: If the temperature at the controller is below -4ºF
(-20ºC), the display refresh rate could be less
responsive.
WARNING: When using a single transformer to power
more than one controller or expansion
module, the correct polarity must always be
maintained between the boards. Failure to
observe correct polarity will result in damage
to the unit controller, RSMD, and any associated
module.
Please carefully read and apply the following information when
wiring the unit controller, RSMD, and any associated module.
• All wiring is to be in accordance with local and national
electrical codes and specications.
• All 24 VAC wiring must be connected so that all ground
wires remain common. Failure to follow this procedure can
result in damage to the controller and connected devices.
• Minimum wire size for 24 VAC wiring should be 18-gauge.
• Minimum wire size for all sensors should be 24-gauge.
Some sensors require two-conductor wire and some require
three-or four-conductor wire.
• Minimum wire size for 24 VAC thermostat wiring should
be 22-gauge.
• Be sure that all wiring connections are properly inserted
and tightened into the terminal blocks. Do not allow wire
strands to stick out and touch adjoining terminals which
could potentially cause a short circuit.
• When communication wiring is used to interconnect
HVAC unit controllers together or to connect to other
communication devices, all wiring must be plenum-rated,
minimum 18-gauge, two-conductor, twisted pair with
shield. AAON can supply communication wire that meets
this specication and is color coded for the network or
local loop. Please consult your AAON distributor for
information. If desired, Belden #82760 or equivalent wire
may also be used.
• Before applying power to the HVAC unit controller, RSMD
Modules, and any associated modules, be sure to recheck
all wiring connections and terminations thoroughly.
Powering Up
When the controller and modules are rst powered up, the POWER
LED should light up and stay on continuously. If it does not light up,
check to be sure that you have 24 VAC connected to the controller,
that the wiring connections are tight, and that they are wired for
the correct polarity. The 24 VAC power must be connected so that
all ground wires remain common. If after making all these checks,
the POWER LED does not light up, please contact AAON Controls
Support for assistance.

8RSMD Technical Guide
WIRING
Inputs Wiring
RSMD Wiring
The RSMD monitors and controls one or two refrigeration circuits
of the HVAC unit. The module is designed for R410-A refrigerant.
The RSMD is connected to the VCCX2 Controller. Up to four
RSMD Modules can be connected, depending on the size of the
system. There are two E-BUS expansion ports which allow the use
of communicating sensors and E-BUS modules.
The RSMD provides three analog inputs, four binary inputs, ve
relays, and two analog outputs. See Figure 2, this page, for inputs
wiring and Figure 3, page 9, for outputs wiring.
WARNING: Observe Polarity! All boards must be wired
with GND-to-GND and 24 VAC-to-24
VAC. Failure to observe polarity will result
in damage to one or more of the boards.
Expansion modules must be wired in such
a way that the expansion modules and the
controller are always powered together. Loss
of power to the expansion module will cause
the controller to become inoperative until
power is restored to the expansion module.
Suction Pressure Transducer Wiring
Suction pressure transducers must be wired as shown in Figure
2, this page. It is typically required for all VCCX2 applications.
Suction pressure transducers are used to measure suction pressure
at the HVAC unit’s DX evaporator coil suction line. This suction
line pressure is converted to saturated refrigerant temperature.
The saturated refrigerant temperature is used to properly control
the compressors to maintain a given Suction Coil (Saturated)
Temperature Setpoint. In Cooling mode, the VCCX2 resets the
Suction Coil (Saturated) Temperature Setpoint to maintain a given
Supply Air Temperature Setpoint. In Dehumidication Mode, the
Suction Coil (Saturated) Temperature Setpoint is a user congurable
setpoint that can be reset based on indoor humidity levels.
GND 18-30
VAC
Comp. Discharge
Temp 1 Sensor
Comp. Discharge
Temp 2 Sensor
Leaving Water
Temp Sensor
Comp Status 1
Comp Status 2
Outside Coil Temp/POWF
Emergency Shutdown
Head Pressure 2
Transducer (by others)
Suction Pressure 1
Transducer
Head Pressure 1
Transducer (by others)
Suction Pressure 2
Transducer
Line Voltage
Size transformer for
correct total load.
RSMD = 18 VA
ALARM
UP
DOWN
ENTERMENU
AAON P/N:ASM02201
+24 VAC
GND
RELAY CONTACT
RATING IS 1 AMP
MAX @ 24 VAC
CONDENSER 1
COMP 1
COMP 2
ANALOG OUT
REVERSING VALVE
COMMON
RELAY OUTPUT
TERMINALS
LABEL P/N:
G041660
COND 1
COND 2
GND
24 VAC
POWER ONLY
WARNING!
POLARITY
MUST BE
OBSERVED
OR THE
CONTROLLER
WILL BE
DAMAGED
CONDENSER 2
HEAD PRES 1
+5 V
+5 V
COMP DIS 1
COMP 1
SP-1
HP-1
COMP DIS 2
COMP 2
GND
GND
OA COIL/POWF
EMER SHDN
GND
LEAVING H20
GND
SUCTION PRES 2
HEAD PRES 2
+5 V
+5 V
SP-2
HP-2
GND
GND
R+
SHD
T-
R+ SHD T-
E-BUS DUAL E-BUS
EXPANSION
RSM FOR DIGITAL COMPRESSORS
www.aaon.com
SUCTION PRES 1
RD
WT
BL
RD
WT
BL
RD
WT
BL
RD
WT
BL
Figure 2: RSMD Inputs Wiring

9RSMD Technical Guide
WIRING
Outputs Wiring
CAUTION: The Shraeder port used for installation of the
suction pressure transducer should be located in
a vertical position of the suction line to prevent
refrigerant oil from accumulating in the sensor.
NOTE: If there are two compressors on a single circuit (a
tandem circuit), Suction Pressure 2, Head Pressure
2, and Condenser Signal 2 would not be used.
Head Pressure Control
The Head Pressure Transducers are used to measure Head Pressure at
the discharge line. This Head Pressure is used to drive the condenser
fans with a 0-10 VDC output signal or valve with a 2-10 VDC output
signal to maintain a given Head Pressure Setpoint.
Compressor Discharge Sensors
The Digital Compressor Discharge Temperature Sensor monitors
the discharge temperature from the digital compressor to protect
against overheating.
Leaving Water Temperature Sensor
The Leaving Water Temperature Sensor is used to measure the
Leaving Water Temperature when used on a WSHP unit.
GND 18-30
VAC
Line Voltage
Size transformer for
correct total load.
RSMD = 18 VA
Belimo actuator wiring
shown. Consult factory for
other manufacturer wiring
instructions.
NOTE:
All relay outputs are normally open
and rated for 24 VAC power only.
1 Amp maximum load.
Digital Compressor 1
24 VAC ONLY
COMPRESSOR 1 ENABLE
COMPRESSOR 2 ENABLE
CONDENSER 1 ENABLE
CONDENSER 2 ENABLE
REVERSING VALVE
Digital Compressor 2
Signal 1
Condenser
Condenser
Signal 2
WSE Bypass
Valve Actuator
Connects to VCCX2
Loop Communications
connector when used on
a split system.
GND
+
GND
+
COM
+
COM
+
1 COM
2 +
3 Y1
GND
TEMP3
TEMP2
TEMP1
TB9
GND +5V
D12
BIN4
D11
BIN3
D10
BIN2
D9
BIN1
TB12
GND
HP-2
+5V
TB8
GND
J1 C
C
SP-2
+5V
TB6
GND
HP-1
+5V
TB3 POWER
COMM
ALARM
STATU
GND
SP-1
+5V
TB4
YS102632 REV 1
R30 4751
R1
R34 4751
R2
4751 R38
R3
4751 R42
R4
4751 R58
R5
COM
V6
TB7
COMP1
24VAC
P6
COMP2
TB11
AOUT 1
AOUT 2
GND
P2
HH485
R+
GND
T-
TB2
C20
.01uF
I
O
I
O
OMRON
G5Q-1A4
DC12V
SA
5A30VDC
CHINA 10A250VAC~
R14
R27
R28 R31
R32 R35
R36 R39
R40 R44
R43
C43
R49
R48
R56
R54
1002
1002
1002
1002
1002
1002
.1uF
1002
1002
.1uF
1002
1002
.1uF
1002
1002
.1uF
1002
1002
.1uF
1002
1002
SERIAL #
ALARM
UP
DOWN
ENTERMENU
AAON P/N:ASM02201
+24 VAC
GND
RELAY CONTACT
RATING IS 1 AMP
MAX @ 24 VAC
CONDENSER 1
COMP 1
COMP 2
ANALOG OUT
REVERSING VALV E
COMMON
RELAY OUTPUT
TERMINALS
LABEL P/N:
G041660
COND 1
COND 2
GND
24 VAC
POWER ONLY
WARNING!
POLARITY
MUST BE
OBSERVED
OR THE
CONTROLLER
WILL BE
DAMAGED
CONDENSER 2
HEAD PRES 1
+5 V
+5 V
COMP DIS 1
COMP 1
SP-1
HP-1
COMP DIS 2
COMP 2
GND
GND
OA COIL/POWF
EMER SHDN
GND
LEAVING H20
GND
SUCTION PRES 2
HEAD PRES 2
+5 V
+5 V
SP-2
HP-2
GND
GND
R+
SHD
T-
R+ SHD T-
E-BUS DUAL E-BUS
EXPANSION
RSM FOR DIGITAL COMPRESSORS
www.aaon.com
SUCTION PRES 1
Connect to
VCCX2 Controller
Figure 3: RSMD Outputs Wiring

10RSMD Technical Guide
INPUTS AND OUTPUTS
Inputs/Outputs Map
Inputs/Outputs Map
See Table 2, this page, for the RSMD inputs and outputs.
REFRIGERATION SYSTEM MODULE
FOR DIGITAL COMPRESSORS
Analog Inputs
1Suction Pressure 1 Transducer (SP-1)
2Head Pressure 1 Transducer (HP-1)
3Suction Pressure 2 Transducer (SP-2)
4Head Pressure 2 Transducer (HP-2)
5Compressor Discharge Temperature Sensor 1 (TEMP1)
6Compressor Discharge Temperature Sensor 2 (TEMP2)
7Leaving Water Temperature Sensor (TEMP3)
Binary Inputs
1Compressor Status 1 (BI1)
2Compressor Status 2 (BI2)
3Outdoor Coil Temperature / Proof of Water Flow (BI3)
4Emergency Shutdown (BI4)
Analog Outputs (0-10 VDC)
1Condenser 1 Fan Signal (AO1)
2Condenser 2 Fan Signal (0-10 VDC) or WSE Bypass
Actuator (2-10 VDC) (AO2)
Relay Outputs (24 VAC)
1Compressor 1 Enable Relay (RLY1)
2Compressor 2 Enable Relay (RLY2)
3Condenser 1 Enable Relay (RLY3)
4Condenser 2 Enable Relay (RLY4)
5Reversing Valve Relay (RLY5)
Table 2: RSMD Inputs and Outputs

11RSMD Technical Guide
INPUTS AND OUTPUTS
Inputs and Outputs
RSMD - Inputs and Outputs
+5V – VDC Power
This output is a 5 VDC output that supplies power to the Suction
Pressure Transducers.
SP-1 and SP-2 – Suction Pressure Transducers
The Suction Pressure Transducers are used to measure suction
pressure at the HVAC unit’s DX evaporator coil suction line.
This suction line pressure is converted to saturated refrigerant
temperature. The saturated refrigerant temperature is used to
properly control the compressors to maintain a given Suction Coil
(Saturated) Temperature Setpoint. In Cooling Mode, the VCCX2
resets the Suction Coil (Saturated) Temperature Setpoint to maintain
a given Supply Air Temperature Setpoint. In Dehumidication
Mode, the Suction Coil (Saturated) Temperature Setpoint is a user
congurable setpoint that can be reset based on indoor humidity
levels.
+5V – VDC Power
This output is a 5 VDC output that supplies power to the Head
Pressure Transducers.
HP-1 and HP-2 – Head Pressure Transducers
The Head Pressure Transducers are used to measure Head Pressure at
the discharge line. This Head Pressure is used to drive the condenser
fans to maintain a given Head Pressure Setpoint.
TEMP1 and TEMP2 – Compressor Discharge
Temperature Sensor 1 and Sensor 2 Input
The Digital Compressor Discharge Temperature Sensors monitor
the discharge temperature from the digital compressor to protect
against overheating.
TEMP3 – Leaving Water Temperature Sensor Input
This input monitors the condenser leaving water temperature and
determines if the condenser is operating in a safe water temperature
range.
BI1 – Compressor Status 1
When this wet contact input closes, a 24 volt signal indicates
Compressor 1 is running. Typically, the source for this is the auxiliary
contacts on the compressor contactor after it has run through the
compressor safeties. If Binary Input 1 opens, Compressor 1 Enable
Relay de-energizes and a compressor alarm is generated.
BI2 – Compressor Status 2
When this wet contact input closes, a 24 volt signal indicates
Compressor 2 is running. Typically, the source for this is the auxiliary
contacts on the compressor contactor after it has run through the
compressor safeties. If Binary Input 2 opens, Compressor 2 Enable
Relay de-energizes and a compressor alarm is generated.
BI3 – Outdoor Coil Temperature / Proof of Water Flow
Status
This input can be used for the following two options:
• Air to Air Heat Pump: This wet contact input monitors a
defrost coil temperature switch on air to air heat pump units.
If the compressors are operating in the Heating Mode and
this switch closes, it initiates a Defrost Mode.
• Water Source Heat Pump: This wet contact input is for
the Water Proof of Flow Switch. If the Water Proof of
Flow Switch contact opens while the condenser valve
is operating, the controller reacts to protect the system
depending on the current mode of operation.
BI4 – Emergency Shutdown
This wet contact input is used to initiate shutdown of the HVAC
unit when a normally closed smoke detector (by others), restat (by
others), or other shutdown condition (by others) contact is opened.
The controller remains active and can initiate alarm relays.
NOTE: The binary inputs require wet contacts (24 VAC
only) to recognize an active input. If a dry contact is
provided, the contact closure will not be recognized.
AO1 – Condenser 1 Fan Signal
This 0–10 VDC output is used to control/modulate the Condenser
1 Fan / Valve to maintain the Head Pressure Setpoint.
AO2 – Condenser 2 Fan Signal or Waterside
Economizer Bypass Actuator Valve
This 0–10 VDC output is used to control/modulate the Condenser
2 Fan / Valve to maintain the Head Pressure Setpoint or this output
signal is a Direct Acting 2–10 VDC output signal that is used to
modulate the Waterside Economizer Bypass Actuator.
RLY1 – Compressor 1 Enable
This relay enables Compressor 1.
RLY2 – Compressor 2 Enable
This relay enables Compressor 2.
RLY3 – Condenser 1 Enable
This relay enables Condenser 1 Fan / Water Valve.
RLY4 – Condenser 2 Enable
This relay enables Condenser 2 Fan / Water Valve.
RLY5 – Reversing Valve Enable
This relay enables the Reversing Valve.

12RSMD Technical Guide
SEQUENCE OF OPERATIONS
Cooling Mode, Dehumidication, and Head Pressure Control
Cooling Mode Operation
In Cooling Mode, as the Supply Air Temperature (SAT) rises above
the Active SAT Cooling Setpoint, the compressors stage on and
modulate to maintain the Active Evaporator Coil Suction (Saturated)
Temperature Setpoint. Two compressors are controlled per RSMD.
Multiple RSMD Modules are needed when there are more than
two compressors.
One Digital and One Fixed Compressor
In units with one digital and one xed compressor, if the digital
compressor modulates to 100% and the SAT is still above the SAT
Cooling Setpoint for the Cooling Stage Up Delay, then the xed
compressor stages on. The digital compressor is then allowed to
modulate as necessary to maintain the Active Evaporator Coil
Suction (Saturated) Temperature Setpoint. Minimum o times must
also be met before compressors can stage on.
Multiple Digital Compressors
In units with multiple digital compressors, if the first digital
compressor modulates to 100% and the SAT is still above the SAT
Cooling Setpoint for the Cooling Stage Up Delay, then the second
digital compressor enables and the two digital compressors modulate
together to maintain the Active Evaporator Coil Suction (Saturated)
Temperature Setpoint.
To stage down compressors, if the digital compressor(s) have
modulated down to 30% for the Stage Down Delay period and the
SAT has fallen below the SAT Cooling Setpoint minus the Stage
Control Window, then the last compressor to have staged on (digital
or xed) will stage o – assuming its minimum run time has been
met. Any remaining digital compressors are allowed to modulate
as needed. If the last remaining digital compressor reaches 0% for
the Stage Down Delay, it will stage o.
Dehumidication Operation
The RSMD activates the Cooling Stages based on the Evaporator
Coil Temperature compared to the Evaporator Coil Suction
(Saturated) Temperature Setpoint. The Evaporator Coil Suction
(Saturated) Temperature is calculated by using the Suction Pressure
Transducer and converting the pressure to temperature.
For Copeland Digital Scroll Compressor units, the RSMD modulates
the Copeland Digital Scroll Compressor to maintain the Evaporator
Coil Suction (Saturated) Temperature Setpoint and activate the
compressors as necessary.
On units that have one digital and one xed capacity compressor,
if the xed capacity compressor is activated, the Copeland Digital
Scroll Compressor is only allowed to modulate within the range
of 70–100% in order to prevent the loss of reheat capacity during
low load conditions.
With both compressors on, if the rst digital compressor has
modulated down to its 70% minimum and the Coil Suction
Temperature falls below the Coil Temperature Setpoint minus the
Cooling Stage Control Window, then the second compressor stages
o once its Compressor Minimum Run Time and the Stage Down
Delay Time have been met. At that point, the Copeland Digital
Scroll Compressor can modulate down as needed to maintain the
Coil Temperature Setpoint.
If the RSMD has two digital compressors, the rst compressor will
be locked at 100% and the second compressor will modulate.
Head Pressure Control
The RSMD can monitor a Head Pressure Transducer and control a
condenser fan to maintain a Head Pressure Setpoint. The module
must be congured for an air cooled condenser.
A condenser relay is commanded on when the rst compressor is
enabled (except if the unit is in Heat Pump Defrost Mode). On an
air cooled unit, the condenser fan is controlled with 0–10 VDC
output signal.
When the Condenser Signal rst activates, it maintains at 100%
for 10 seconds.
In the Cooling Mode, the Condenser Cignal modulates to maintain
the Cooling Head Pressure Setpoint. The signal can modulate
between 15% and 100%. If the head pressure exceeds 550 psi, the
condenser control signal immediately goes to 100% and a High
Head Pressure Alarm is generated. The alarm is deactivated when
the Head Pressure drops below 540 psi.
In the Dehumidication Mode, the condenser output signal controls
to the Reheat Head Pressure Setpoint. High head pressure conditions
produce the same eects as in the Cooling Mode.
If no Head Pressure Transducer is detected, the Condenser Output
Signal is maintained at 100%.

13RSMD Technical Guide
LCD SCREENS
LCD Display Screen and Navigation Keys
LCD Display Screen and Navigation Keys
The LCD display screens and buttons show status and alarms, and
enable force modes. See Figure 4, this page, and refer to Table 3,
this page, for descriptions.
ALARM
UP
DOWN
ENTERMENU
Figure 4: LCD Display and Navigation Keys
NAVIGATION KEY FUNCTIONS
Navigation
Key Key Function
MENU Use the MENU key to move through screens
within Main Menu categories and return to the
Main Menu while at other screens.
UP Use this key to adjust setpoints and change
congurations.
DOWN Use this key to adjust setpoints and change
congurations.
ENTER Use the ENTER key to navigate through the
Main Menu Screen categories.
Table 3: Navigation Key Functions

14RSMD Technical Guide
LCD SCREENS
Screens Map
RSMD
1067VXXX
SYSTEM
STATUS
SENSOR
STATUS
ALARMS ALARM
HISTORY
SETPOINT
STATUS
EBUS COMM
PACKETS
SOFTWARE
1067VXXX
BOARD/EBUS
ADDRESS
#COMP
CONFIGURED
#COND
CONFIGURED
COMP A1
DIGITAL
COMP B2
FIXED
MODE
OFF
COMP A1
ON
COMP B2
OFF
COND 1 FAN
20%
SUCTION 1
XXX PSI
HEAD PR1
XXX PSI
SUCTION 2
XXX PSI
HEAD PR2
XXX PSI
HEADPRSP
340 PSI
FAN ON
XX PSI
COILT SP
35 F
COND 2 FAN
OFF
BYPS VLV
CLOSED
DEFROST
10 MINS
H2O FLOW
YES
CALC CT1
XX F
CALC CT2
XX F
COMPTMP1
XX F
COMPTMP2
XX F
H2O TEMP
XX F
FAN OFF
XX PSI
GLYCOL %
XX %
LOW SUCT
95 PSI
LOW H2O
37 F
DEFR INT
30 MIN
or if congured
for water source
heat pump
or if congured
for water source
heat pump
If congured
for modulating
condenser, the
following screen
displays
If congured for fan
cycle, the following
two screens display
If congured for
water source heat
pump, the following
three screens
display
If congured for air
to air heat pump,
the following screen
displays

15RSMD Technical Guide
LCD SCREENS
Screen Descriptions
Main Screens
Refer to Table 4, this page, when navigating through the LCD
Main Screens.
Press the <MENU> button to navigate between the top level screens.
Press the <ENTER> button to scroll through the next level screens,
MAIN SCREENS
Screen Text Description
RSMD
1067vxxx
Refrigeration module screens.
SYSTEM
STATUS
System status screens.
SENSOR
STATUS
Sensor status screens.
ALARMS Alarms screens. Screen shows NO
ALARMS if no alarms are active.
ALARM
HISTORY
Alarm history screens.
SETPOINT
STATUS
Setpoint status screens.
Table 4: Main Screens
Module Screens
Refer to Table 5, this page, when navigating through the RSMD
Screens. From the RSMD Screen, press <ENTER> to scroll through
the screens.
MODULE SCREENS
Screen Text Description
RSMD
1067vxxx
Refrigeration module screens
EBUS
+X
E-BUS communication diagnostics with
X being the number of COMM packets
received. The number increases as
packets are received.
SOFTWARE
1067vxxx
Current software version. Access the
protected screens from this screen by
holding the <UP> button for ve seconds.
ADDRESS
1(152)A
Current board address.
BoardAddress(EBUS Address)CircuitLetter
The rst number is the board address.
The second number is the EBUS address.
The third number is the circuit letter.
#OF COMP
1
Number of compressors congured.
#OF COND
1
Number of condensors congured.
COMP A1
DIGITAL
Compressor A1 or B1 type, xed or digital
COMP B2
FIXED
Compressor A2 or B2 type, xed or digital
(if second compressor installed).
Table 5: Module Screens

16RSMD Technical Guide
LCD SCREENS
Screen Descriptions
System Status Screens
Refer to Table 6, this page, when navigating through the System
Status Screens. From the SYSTEM STATUS Screen, press
<ENTER> to scroll through the screens.
SYSTEM STATUS SCREENS
Screen Text Description
SYSTEM
STATUS
System status screens
MODE
OFF
System Mode. Options are:
OFF
COOL
HEAT
DEHUMID
FORCED
COMP A1
ON
Compressor A1 or B1 (based on board address)
Options are:
OFF - Compressor is o󰀨.
0-100% - Modulating % position
COMP B2
OFF
Compressor A2 or B2 (based on board address)
Options are:
ON - Compressor is on.
OFF - Compressor is o󰀨.
FORCED
COND 1 FAN
20%
Condenser 1 Fan. Options are:
OFF - Condenser is o󰀨.
0-100% - Modulating % position
COND 2 FAN
OFF
Condenser 2 Fan. Options are:
OFF - Condenser is o󰀨.
0-100% - Modulating % position
BYPS VLV
CLOSED
Waterside Economizer Bypass Valve
CLOSED: Valve is closed
1-100% - Modulating % position
DEFROST
10 MINS
Defrost interval timer in number of minutes
H2O FLOW
YES
Water ow. Options are:
ON
OFF
This screen appears instead of the defrost
interval timer If the system is congured with a
water source heat pump,
Table 6: System Status Screens
Sensor Status Screens
Refer to Table 7, this page, when navigating through the Sensor
Status Screens. From the SENSOR STATUS Screen, press
<ENTER> to scroll through the screens.
SENSOR STATUS SCREENS
Screen Text Description
SENSOR
STATUS
Sensor status screens
SUCTION 1
XXX PSI
Suction Pressure 1 reading from input. Measured
in psi.
HEAD PR1
XXX PSI
Head Pressure 1 reading from input. Measured
in psi.
SUCTION 2
XXX PSI
Suction Pressure 2 reading from input. Measured
in psi.
HEAD PR2
XXX PSI
Head Pressure 2 reading from input. Measured
in psi.
CALC CT1
XX F
Calculated Coil Temperature 1 from Suction
Pressure 1 input. Measured in ºF.
CALC CT2
XX F
Calculated Coil Temperature 2 from Suction
Pressure 2 input. Measured in ºF.
COMPTMP1
XX F
Compressor Temperature 1 reading from Head
Pressure 1 input. Measured in ºF.
COMPTMP2
XX F
Compressor Temperature 2 reading from Head
Pressure 2 input. Measured in ºF.
H2O TEMP
XX F
Water temperature reading from Leaving Water
Temperature Sensor.
This screen appears if the system is congured
with a water source heat pump,
Table 7: Sensor Status Screens

17RSMD Technical Guide
LCD SCREENS
Screen Descriptions
Alarms Screens
If an alarm is present, the ALARM LED above the LCD display lights up red and blinks. The alarms display and scroll automatically
from the ALARMS screen when alarms are present. Refer to Table 8, this page, for descriptions.
ALARMS SCREENS
Screen Text Description
ALARMS Alarms status screens
NO
ALARMS
No Alarms. This is shown if there are no current alarms.
EBUS SLV
TIMEOUT
EBUS Slave Timeout. This alarm indicates communication has been lost between the RSMD and the controller or other E-BUS
modules that may be connected. This can be the result of a bad cable, a missing cable, or the module not being congured
properly.
NO SUCTx
DETECTED
No Suction Pressure Detected. This alarm indicates the Suction Pressure Transducer is not detected by the system. The module
goes into alarm and shuts down the compressor.
NO HEADx
DETECTED
No Head Pressure Detected. This alarm indicates the Head Pressure Transducer is not detected by the system. This causes the
condenser fan/valve to go to 100%.
HIGH HPx
DETECTED
High Head Pressure Detected. This alarm indicates a high head pressure alarm condition which is activated when the head
pressure rises above 550 psi. This causes the condenser to go to 100%.
LOW SPx
FAILURE
Low Suction Pressure Failure. This alarm occurs if suction pressure stays below the Low Suction Pressure Setpoint for one
minute or falls below 40 psi for ve seconds. This alarm shuts down the system. Power must be cycled to clear the alarm.
LOW SPx
DETECTED
Low Suction Pressure Detected. This alarm occurs if suction pressure falls below the Low Suction Pressure Setpoint for 20
seconds. The system will try to protect itself by lowering compressor modulation percentage.
COMPx
FAULT
Compressor Fault. This alarm occurs if the compressor fails to run 45 seconds after the relay is activated or if the signal is lost
after activation. This causes an alarm and shuts down the compressor enable relay. The system will retry after ve minutes.
COMPx
BADTEMP
Compressor Bad Temperature. This alarm occurs if the Discharge Temperature Sensor measures less than -40ºF or more than
356ºF. This will cause an alarm and will shut down the compressor enable relay. The system will retry after ve minutes.
COMPx
CUTOFF
Compressor Cuto󰀨. This alarm occurs if the Discharge Temperature Sensor measures more than 265ºF. This will cause an alarm
and will shut down the compressor enable relay. The system can be restarted after 30 mintues.
COMP
LOCKOUT
Compressor Lockout. This alarm occurs if an active cuto󰀨 happens ve times within a four-hour period, the compressor will be
locked out. Power must be cycled to clear the alarm.
• If a circuit’s suction pressure falls twice within a two hour window below the Low Suction Pressure Setpoint for longer than
one minute each time, the compressor on that circuit will be locked out. Manual reset or change of mode is required to
return to normal operation.
• If the suction pressure falls below the Unsafe Suction Setpoint for ve seconds, that circuit’s compressor will be locked out.
Power will need to be cycled to restart the unit.
• If the Leaving Water Temperature falls below the setpoint, the last compressor will be locked out until the Leaving Water
Temperature rises 6ºF above the setpoint.
• The Leaving Water Temperature remains below the setpoint for one minute or falls 3ºF below the setpoint. This alarm will
disable when the Leaving Water Temperature rises 12ºF above the setpoint.
NO WATER
FLOW
No Proof of Water Flow. This alarm occurs if there is a call for a compressor and the proof of ow binary input does not see 24
VAC for more than three minutes or if during Heat Pump Heating Mode, the proof of ow binary input is open for more than two
seconds. This alarm will disable when the proof of ow binary input is enabled.
LOW H2O
TEMP
Low Water Temperature. This alarm occurs if both compressors are on and water temperature goes below setpoint, Compressor
2 will fail. If both compressors are on and water temperature goes 3ºF below the setpoint, both compressors will fail. If
Compressor 2 is o󰀨 or failed and water temperature is still low for one minute, Compressor 1 will also fail. This alarm disables
when the Leaving Water Temperature rises 6ºF above the setpoint.
EMERGNCY
SHUTDOWN
Emergency Shutdown. This alarm occurs if the Emergency Shutdown Binary Input is not activated. This alarm shuts o󰀨 the
compressors.
COMPx
FALSE
Compressor False Active Input. This alarm occurs if the compressor enable relay is o󰀨 but the compressor status binary input is
activated for 60 seconds.
ENVELOPE
FAULT
WSHP Heating out of Envelope Fault. This alarm occurs if the circuit is running below the envelope consecutively for one minute.
The compressor(s) on the circuit fails and an alarm is generated. The system will retry after ve minutes.
Table 8: Alarms Screens

18RSMD Technical Guide
LCD SCREENS
Screen Descriptions
Alarm History Screens
The ALARM HISTORY screen displays past alarms, if any, and how
long ago the last of each type occurred. From the ALARM HISTORY
screen, press <ENTER> to scroll through the history screens.
The rst line is the ALARM NAME.
The second line shows how long ago each alarm last occurred. The
screen displays:
• Minutes for the rst 60 minutes of alarm occurrence
• Hours for the next 72 hours of alarm occurrence
• Days for the next 30 days of alarm occurrence
Alarms clear after 30 days.
NOTE: Alarm history is not stored in memory. If power is
lost, the alarms will clear.
The ALARM HISTORY screens follow the same sequence as the
ALARMS screens but are abbreviated dierently to allow space to
show the time since last occurence.
ALARM HISTORY SCREENS
Screen Text Description
NO ALARM
HISTORY
No alarm history.
Table 9: Alarm History Screens
Setpoint Status Screens
Refer to Table 10, this page, when navigating through the Setpoint
Status Screens. From the SETPOINT STATUS Screen, press
<ENTER> to scroll through the screens.
SETPOINT STATUS SCREENS
Screen Text Description
SETPOINT
STATUS
Setpoint Status screens
COILT SP
35 F
Coil Temperature Setpoint Status. Valid range
is 35 to 70 degrees. Default is 35ºF.
HEADPRSP
340 PSI
Head Pressure Setpoint Status. Valid range is
275 to 475 PSI. Default is 340 psi.
Appears if the system is congured for
modulating condenser.
FAN ON
XX PSI
Head Pressure Reaading when fan cycle is on.
Appears if the system is congured for fan
cycle.
FAN OFF
XX PSI
Head Pressure Reading when fan cycle is o󰀨.
Appears if the system is congured for fan
cycle.
GLYCOL %
X%
Glycol Percentage Status
Appears if congured for water source heat
pump.
LOW SUCT
95 PSI
Low Suction Pressure Setpoiont Status.
Default is 95 psi.
Appears if congured for water source heat
pump.
LOW H2O
37 F
Low Leaving Water Temperature Setpoint
Status. Default is 37ºF.
Appears if congured for water source heat
pump.
DEFR INT
30 MIN
Defrost Interval Setpoint Status. Default is 30
minutes.
Appears if the system is congured for air to air
heat pump.
Table 10: Setpoint Status Screens

19RSMD Technical Guide
LCD SCREENS
Protected Screen Map
Protected Screens Map
Refer to the following map when navigating through the LCD Protected Screens. From the RSMD Screen, press <ENTER> twice to get to
the SOFTWARE Screen. Then hold the <UP> button for ve seconds. To scroll through the rest of the screens, press the <MENU> button.
RSMD
1067VXXX
E-BUS
+0
SOFTWARE
1067VXXX
DIAGNSTC ADDRESS
1(152)
ENTER TO
EXIT
Hold 5 seconds.
CONFIG ALARM
COUNTS

20RSMD Technical Guide
LCD SCREENS
Protected Screen Descriptions
Conguration Screens Map
Refer to the following map when navigating through the
Conguration Screens. From the CONFIG Screen, press <ENTER>
to scroll through the screens.
CONFIG
COND FAN
LOCKED
LOCK POS
100%
Conguration Screens
Refer to Table 11, this page, when navigating through the
Conguration Screens. From the CONFIG Screen, press <ENTER>
to scroll through the screens.
DIAGNOSTIC SCREENS
Screen Text Description
CONFIG Diagnostic screens
COND FAN
LOCKED
Condenser Fan. Locked or unlocked
LOCK POS
100%
Condenser fan locked position.
Table 11: Conguration Screens