Trane Tracer UC400 Installation and operating instructions

SSAAFFEETTYY WWAARRNNIINNGG
Only qualified personnel should install and service the equipment The installation, starting up, and servicing of heating, ventilating, and air-conditioning
equipment can be hazardous and requires specific knowledge and training Improperly installed, adjusted or altered equipment by an unqualified person
could result in death or serious injury When working on the equipment, observe all precautions in the literature and on the tags, stickers, and labels that
are attached to the equipment
February 2021 BBAASS--SSVVXX006655EE--EENN
Installation, Operation, and Maintenance
Tracer®® UC400/UC400–B
Programmable Controller
Water Source Heat Pump (WSHP)

©2021 Trane BAS-SVX065E-EN
Introduction
NNoottee:: Specific reference to either UC400 or UC400–B is made throughout this document. All
other content cited in this document about the UC400 is referred to as UUCC440000 CCoonnttrroolllleerr.
The UC400/UC400–B is a multi-purpose, programmable (or application-specific) that provides
direct-digital zone temperature control This controller can operate as a stand-alone device or as
part of a building automation system (BAS) Communication between the controller and a BAS
occurs on an open standard with inter-operable protocols used in Building Automation and
Control Networks (BACnet®) Programming is done by means of the Tracer®TU service tool
This guide provides installation and configuration information for the UC400 Controller with
specific operation description for Water Source Heat Pump (WSHP)
Copyright
This document and the information in it are the property of Trane, and may not be used or
reproduced in whole or in part without written permission Trane reserves the right to revise this
publication at any time, and to make changes to its content without obligation to notify any
person of such revision or change
Trademarks
All trademarks referenced in this document are the trademarks of their respective owners
Agency Listings and Compliance
The European Union (EU) Declaration of Conformity is available from your local Trane®office
evision History
• Updated table 7 "Output test states" in chapter Typical Applications and Terminations
• Added new topic "Constant Torque ECM Fans" in Sequence of Operation chapter
• Changed the Dehumidification text to Active Dehumidification
• Added new topic "Passive Dehumidification" in Sequence of Operation chapter
• Added "Unit Configuration" diagnostics cause and diagnostics in table 18
• Running edits

BAS-SVX065E-EN 3
BACnet Protocol 5
BACnet®Testing Laboratory (BTL) Certification 5
Specifications and Dimensions 6
Device Connections 8
Additional Components 10
Water, Discharge, and Outdoor Air Temperature Sensors 10
Binary Input Switching Devices 10
Zone Temperature Sensors 10
Valve and Damper Actuators 11
Zone Humidity Sensor 11
Expansion Modules 11
Typical Applications and Terminations 12
Binary Inputs 14
BI1; Occupancy 14
BI2; Compressor 1 Protection Status 14
BI3; Compressor 2 Protection Status 14
BI3/BI4; Frost Detection 14
BI5; Fan Status 14
Analog Inputs 15
Ground Terminals 15
AI1; Space Temperature 15
AI2; Space Temperature Local Setpoint 15
AI3; Local Fan Mode Input 15
AI4; Discharge Air Temperature Sensor 15
AI5; Entering Water Temperature 16
Universal Inputs 16
UI1; Leaving Water Temperature 16
UI2; Relative Humidity or CO2Sensor 16
Pressure Inputs 16
PI1; Condensate Overflow 16
Wiring Requirements 16
UC400 Wiring Diagrams 17
UC400–B Wiring Diagrams 22
Wiring Installation 27
Connecting Wires to Terminals 27
BACnet MS/TP Link 27
MAC Address 27
BACnet Device ID 27
BACnet Networks, With or Without Tracer SC Controller 27
Table of Contents

4BAS-SVX065E-EN
Without a Tracer SC Controller 27
With a Tracer SC Controller 27
BACnet MS/TP Link Wiring 28
Power Supply 29
Transformer Recommendations 29
Wiring Requirements 29
Connecting 24 Vac Secondary Wires 30
Power On Check 31
LED Description, Activities, and Troubleshooting 32
Sequence of Operation 35
Power-up Sequence 35
Random Start 35
Occupancy Modes 35
Occupied Mode 36
Unoccupied Mode 36
Occupied Standby Mode 36
Occupied Bypass Mode 37
Timed Override Control 37
Heat/Cool Operation 37
Fan Operation 38
Single-Zone VAV/Variable Speed Fan Operation 38
Entering Water Temperature Sampling Function 40
Electric Heat Operation 42
Other Modes 43
Operational Troubleshooting 47
Diagnostics 47
Override Outputs 48
Resetting Diagnostics 50
High/Low Pressure Cutout 50
Manual Output Test 50
Cycling Power 50
Building Automation System (BAS) 50
Tracer TU Service Tool 50
Cycling the Fan Switch 50
Operational Causes and Diagnostics 51
Configuration and Maintenance 54
Resources 57
TTaabbllee ooff CCoonntteennttss

BAS-SVX065E-EN 5
BACnet Protocol
The Building Automation and Control Network (BACnet®) protocol is ANSI/ASHRAE Standard
135 This standard allows building automation systems or components from different
manufacturers to share information and control functions BACnet®provides building owners
the capability to connect various types of building control systems or subsystems together for
many uses Multiple vendors can use this protocol to share information for monitoring and
supervisory control between systems and devices in a multi-vendor interconnected system The
BACnet®protocol defines standard objects (data points) called BACnet®objects Each object has
a defined list of properties that provide context information about that object In addition,
BACnet®defines a number of application services that are used to interact with objects in a
BACnet®device
BACnet®® Testing Laboratory (BTL) Certification
The UC400 Controller supports the BACnet communication protocol and has been designed to
meet the requirements of the application-specific control profile For more details, refer to the
BTL web site at www bacnetinternational org The UC400 Controller supports the following
equipment when used as an application-specific unit:
• Blower Coils
• Fan Coils
• Unit Ventilators
• WSHP
• VAV

6BAS-SVX065E-EN
Specifications and Dimensions
Table 1. UC400/UC400–B specifications
Storage
Temperature: –48°F to 203°F (–44°C to 95°C)
Relative Humidity: Between 5% and 95% (non-condensing)
Operating
Temperature: –40°F to 158°F (–40°C to 70°C)
Humidity: Between 5% and 95% (non-condensing)
Input Power: 20.4–27.6 Vac (24, ±15% nominal), 50Hz to 60Hz, 24 VA
(24 VA plus binary output loads for a maximum of 12 VA for each binary output)
Mounting Weight of
Controller:
Supporting mounting surface: must be 0.80 lb. (.364 kg)
Environmental Rating
(Enclosure):
NEMA 1
Altitude: 6,500 ft. maximum (1,981 m)
Installation: U.L. 840: Category 3
Pollution: U.L. 840: Degree 2
Housing Material:(a) Polycarbonate/ABS Blend
UV protected
U.L. 94-5VA flammability rating
Mounting: UC400: Mounts on EN 50 022 - 35 X 15 DIN rail.
UC400–B: Pre-mounted.
Agency Listing
UL916 PAZX, Open Energy Management Equipment
UL94-5V, Flammability
CE Marked
FCC Part 15, Subpart B, Class B Limit
AS/NZS CISPR 22:2006
VCCI V-3/2008.04
ICES-003, Issue 4:2004
Communications BACnet®MS/TP, supports BACnet Protocol ASHRAE 135-2004 and Meets BACnet Testing Laboratory (BTL) as an Application
Specific Controller (ASC) Profile Device
(a) Not applicable for the UC400-B model.

BAS-SVX065E-EN 7
Figure 1. UC400 and UC400–B dimensions
5.65 in. (143.5 mm)
(*8 Units)
4.00 in.
(101.6 mm)
2.37 in. (60.1 mm)
*DIN Standard 43 880, Built-in Equipment for Electrical Installation. Overall Dimensions and Related Mounting Dimensions.
1.89 in. (48 mm)
1.79 in. (45.4 mm)
14 Pin AMP
BO4
BO5
24VAC
GND BO6
BO7 BI2 BI2 BI3 BI3 AI5
GND
24VAC GND
14 13 12 11 10 9 8 7 6 5 4 3 2 1
J9
USB
J10
3 Pin
Mini
AMP
Service
J18
3 Pin
Mini
AMP
BO7
24VAC
J14 - JST
BO6
0
5
3
8
0
5
3
8
1
5
3
8
0
1
5
3
8
0
Address
AIP4 GND
J2
4 Pin Phoenix
24VAC GND 24VAC GND 24VAC
GND
J15 J17
P1
PI1 PI2
J4
BO9
GND
24VAC BO8
J16
BO1
24VAC
BO2
24VAC
BO3
24VAC
AMP
Phoenix
PhoenixPhoenix
24VDC
GND
Comm +
Comm -
5 pin Phoenix
J8
BACnet
4 Pin Phoenix
J13
AIP3 GND
AIP2
24VAC
AIP1
GND
J1
6 pin Phoenix
J6
AOP2
GND
Phoenix
J5
AOP1
GND
Phoenix
+ - + -
IMC
J12 - AMP
J11 - AMP
BI1 BI1
J3
Phoenix
UIP1
GND
UIP2
GND
24VDC
+
-Gnd 24VDC
1 2 3 4 5 6 1 2 3 4 5 6 123 4
123 4 12 3 4
1
23
4
1
23
4
1 2 3
12
12
21 345
12
1
2
2 1
3
4
56
6.125 in. (155.58 mm)
4.500 in.
(114.30 mm)
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8BAS-SVX065E-EN
Device Connections
The following table provides details of the hardware termination configuration options The
hardware terminations are pre-configured for proper equipment operation for blower coil/fan coil
applications
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Table 2. Connections
Connection Quantity Types Range Notes
Analog input
(AI1 to AI5) 5
Temperature 10 kΩ thermistor AI1 to AI4 can be configured for timed override
capability.
Setpoint 189 Ω to 889 Ω
Resistive 100 Ω to 100 kΩ Typically used for fan speed switch.
Universal input
(UI1 and UI2) 2
Linear 0–20 mA
These inputs may be configured to be thermistor or
resistive inputs, 0–10 Vdc inputs, or 0–20 mA inputs.
Linear 0–10 Vdc
Temperature 10 kΩ thermistor
Setpoint 189 Ω to 889 Ω
Resistive 100 Ω to 100 kΩ
Binary Open collector/dry contact Low impedance relay contacts recommended.
Pulse Solid state open collector Minimum dwell time is 25 milliseconds On and 25
milliseconds Off.
Binary input
(BI1 to BI3)(a) 3
24 Vac detect The UC400 controller provides the 24 Vac required to
drive the binary inputs when using the recommended
connections.
Binary output
(BO1 to BO3)
(a)
3UC400:Relay
• 2.88 A @24 Vac C pilot
duty
• Gen Purpose
–10 A max up 277 Vac
–10 A max up to 30 Vdc
• Motor Duty
–1/3 hp @ 125 VAC
(7.5 A max)
–1/2 hp @ 277 VAC
(7.5 A max)
Power needs to be wired to the binary output. All
outputs are isolated from each other and from ground
or power.
Note: Ranges given are per contact.
Other
Ranges UC400–B:TRIAC 24 Vac Powered
Binary output
(BO4 to BO9)(a) 6 TRIAC
•UC400: 0.5 A max @24-
277 Vac, resistive and pilot
duty
•UC400–B: 24 Vac
Powered
Use for modulating TRIAC. User determines whether
closing high side (providing voltage to the grounded
load) or low side (providing ground to the power
load).
Note: Ranges given are per contact and power comes
from TRIAC SUPPLY circuit.

BAS-SVX065E-EN 9
Table 2. Connections (continued)
Connection Quantity Types Range Notes
Analog output/
binary input
(AO1/BI4 and
AO2/BI5)
2
Linear output 0–20 mA
Each termination must be configured as either an
analog output or binary input.
Linear output 0–10 Vdc
Binary input Dry contact
PWM output 80 Hz signal @ 15 Vdc
Pressure inputs
(PI1 and PI2) 23-wire 0–5 in H2OUsed as a binary input for condensate on WSHP.
Overall Point
Total 23
(a) Do Not mix Class 1 and Class 2 voltage wiring in an enclosure or on a controller without an approved barrier between the wiring.
DDeevviiccee CCoonnnneeccttiioonnss

10 BAS-SVX065E-EN
Additional Components
The UC400 Controller requires the use of additional components for monitoring and proper
control of associated equipment The use of specific components is dependent on the type of
application
NNoottee:: Additional components are not included with the UC400 Controller.
Water, Discharge, and Outdoor Air Temperature Sensors
Temperature sensors must be Trane 10 kΩ (at 25°C) thermistors Entering water and discharge air
inputs can use a sealed temperature sensor (part numbers 4190 1100 and 4190 1133)
Binary Input Switching Devices
Occupancy, condensate overflow, compressor protection, frost detection, and fan status inputs
accept switching devices that may have normally open (NO) or normally closed (NC) dry
contacts
Zone Temperature Sensors
The following table provides the sensor types and features supported by the UC400 Controller
Table 3. UC400 controller supported sensors and features
Features
Sensor
Type Setpoint Fan
Control System Occupancy LEDs Part
Number BAYSENS Global
Parts
Temperature
Sensor No
No No
No
No
X1351152801 BAYSENS077A SEN01448
No Yes X1351153001 BAYSENS073A SEN01450
Temperature
Sensors w/
Fan Control
Single • Off
• Auto
No
Yes
No
X1379084501
N/A
SEN01521
Single
• Off
• Auto
• Low
• High
Yes X1379084801 SEN01524
Single
• Off
• Auto
• Low
• Medium
• High
Yes X1379084201 SEN01518
Temperature
Sensor w/
LCD Display
(a)
Single
• Off
• Auto
• Low
• Medium
• High
No
Can be
configured
for
occupancy
No X1379088604 N/A N/A

BAS-SVX065E-EN 11
Table 3. UC400 controller supported sensors and features (continued)
Features
Sensor
Type Setpoint Fan
Control System Occupancy LEDs Part
Number BAYSENS Global
Parts
Wireless
Zone Sensor
w/Fan
Control
Single
• Off
• Auto
• Low
• Medium
• High
No Yes No
X1379082201
(Sensor Only)
N/A N/A
X1379082401
(Sensor Set)
(a) This sensor can be field configured to match the applicable unit controller options. Unit controller inputs for system status, fan, and service required are
not available on this sensor. If replacing a BAYSENS031A or a BAYSENS035A sensor, and status indicators are required, replace with non-display sensor
BAYSENS109A or BAYSENS110A.
Valve and Damper Actuators
The 2-position analog and 3-wire floating point modulating actuators cannot exceed 12 VA draw
at 24 Vac For 2-position valves, use actuators with ON/OFF and spring actions that returns the
valve to normally open (NO) or closed (NC), which are dependent on the desired default position
For modulating actuators, use actuators with or without a spring return, as required by the
application
Zone Humidity Sensor
For measurement of relative humidity (RH), the UC400 Controller requires a zone humidity
sensor with a 4–20 mA output, where 4 mA is 0% RH and 20 mA is 100% RH The controller
provides 24 Vdc to power the zone humidity sensor
NNoottee:: As an option, the UC400 Controller can recei e humidity from a Trane Air-fi
™ Wireless
Sensor with Humidity.
Expansion Modules
The UC400 Controller can power a maximum of two (2) DC expansion modules (either the Tracer
XM30 or Tracer XM32) without an additional power supply It can support a maximum of 32
additional XM30, XM32 or XM70 hardware terminations when properly applying power
AAddddiittiioonnaall CCoommppoonneennttss

12 BAS-SVX065E-EN
Typical Applications and Terminations
The following tables provide information about supported applications and termination wiring
Table 4. UC400 controller typical applications
Waterside
Economizing Hot Gas Reheat Electric
Heat Boiler-less
Heat Pump
X
X
X
X
X X
X X X
X X X
X X
X X
Cooling Only
X
X
X
X X
X X X
X X
The following table 1 lists 1 or 2 compressor control with discrete 1– or 2–speed fans based on
Trane GE units
Table 5. Factory programmed terminations for Trane GE units
Inputs/Outputs/Communication
UC400/
UC400–
BController
Terminations Factory Programmed Assumed Terminations
Analog Inputs
AI1 Space Temperature Local
AI2 Space Temperature Setpoint Local
AI3 Local Fan Mode Switch
AI4 Discharge Air Temperature Sensor
AI5 Entering Water Temperature Sensor
Universal Inputs
UI1 Relative Humidity Sensor or CO2Sensor
UI2 Leaving Water Temperature
Binary Inputs
BI1 Occupancy
BI2 Compressor 1 lockout status
BI3 Compressor 2 lockout status
Binary Outputs (Relay)
BO1 Fan High
BO2 Waterside Economizer
BO3 Fan Low

BAS-SVX065E-EN 13
Table 5. Factory programmed terminations for Trane GE units (continued)
Inputs/Outputs/Communication
UC400/
UC400–
BController
Terminations Factory Programmed Assumed Terminations
Binary Outputs (TRIAC)
BO4 Compressor 1 Command
BO5 Compressor 2 Command
BO6 Hot Gas Reheat/Electric Heat(a)
BO7 Reversing Valve
BO8 Isolation Valve/External Pump
BO9 Outdoor Air Damper
Analog Outputs/Binary Inputs
AO1/BI4 BI- Frost Detect (Coil Ice Protection)
AO2/BI5 BI- Fan Status
Pressure Inputs
PI1 Condensate Overflow
PI2 Unused
Service Button Test Mode Input
(a) When Hot Gas Reheat and Electric Heat are present on the same WSHP, Electric Heat will be moved to BO1 on XM32.
The following table lists single compressor control with variable speed fan based on Trane EX/
DX units
Table 6. Factory programmed terminations for single compressor control for Trane EX/DX units
Inputs/Outputs/Communication
UC400
Controller
Terminations Factory Programmed Assumed Terminations
Analog Inputs
AI1 Space Temperature Local
AI2 Space Temperature Setpoint Local
AI3 Local Fan Mode Switch
AI4 Discharge Air Temperature Sensor
AI5 Entering Water Temperature Sensor
Universal Inputs
UI1 Relative Humidity Sensor or CO2Sensor
UI2 Leaving Water Temperature
Binary Inputs
BI1 Occupancy Input
BI2 Compressor Protection Status (Monitors High/Low Pressure Cutout
and Freeze Protection)
BI3 Frost Detection
Binary Outputs (Relay)
BO1 Fan Enable
BO2 Water Economizer
BO3 No Connection
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14 BAS-SVX065E-EN
Table 6. Factory programmed terminations for single compressor control for Trane EX/DX units (continued)
Inputs/Outputs/Communication
UC400
Controller
Terminations Factory Programmed Assumed Terminations
Binary Outputs (TRIAC)
BO4 Compressor Enable
BO5 EX Series — No Connection
DX Series — Compressor Step
BO6 Hot Gas Reheat/Electric Heat(a)
BO7 Reversing Valve
BO8 Isolation Valve/External Pump
BO9 Outdoor Air Damper
Analog Outputs/Binary Inputs
AO1/BI4 AO- Variable Speed Fan Control
AO2/BI5 BI- Fan Status
Pressure Inputs
PI1 Condensate Overflow
PI2 No Connection
Service Button Test Mode Input
(a) When Hot Gas Reheat and Electric Heat are present on the same WSHP, Electric Heat will be moved to BO1 on XM32.
Binary Inputs
The UC400 Controller has three (3) binary inputs and two (2) analog outputs/binary inputs
(labeled BI1 through BI5), that can be configured as either analog outputs or binary inputs Each
binary input associates an input signal of 0 Vac with open contacts and 24 Vac with closed
contacts If changes are required, use the Tracer TU service tool to configure each of the inputs as
normally open (NO) or normally closed (NC)
BI1; Occupancy
Occupancy BI1 saves energy by spreading space temperature setpoints when the zone is
unoccupied Used as an occupancy input, BI1 has two (2) related functions:
• It changes the mode from occupied to occupied standby for controllers receiving a BAS-
communicated occupancy request
• It can be hard wired to a binary switch or time clock to determine the occupancy mode as
either occupied or unoccupied for stand-alone controllers
BI2; Compressor 1 Protection Status
Factory programming monitors high and low pressure cutouts and compressor freeze protection
of Compressor 1 on this input
BI3; Compressor 2 Protection Status
Factory programming monitors high and low pressure cutouts and compressor freeze protection
of Compressor 2 on this input
BI3/BI4; Frost Detection
The frost detection sensor detects conditions that produce frost on the coil surface When these
conditions are present, the UC400 Controller detects the condition and generates a Frost
Detection Input alarm
BI5; Fan Status
Fan Status BI5 provides feedback to the UC400 Controller regarding the operating status of the
fan If BI5 is wired to a fan status switch, and the input indicates that the fan is not operating
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss

BAS-SVX065E-EN 15
when the controller has the fan controlled to ON, the controller generates a Low Primary Airflow
Diagnostic
Analog Inputs
The UC400 Controller has seven (7) analog inputs
Ground Terminals
Use the terminal as the common ground for all space temperature sensor analog inputs
AI1; Space Temperature
Space Temperature AI1 functions as the local (hard wired or wireless) space temperature input
The UC400 Controller receives the space temperature as a resistance signal from a 10 kΩ
thermistor in a standard Trane space temperature sensor that is wired to analog input AI1 A
space temperature value communicated by means of a BACnet link, can be used for controllers
operating on a BAS When both a hard wired and communicated space temperature value are
present, and in service, the controller uses the communicated value
If neither a hard wired nor a communicated space temperature value is present, the space
temperature local and active points go into a fault state and generates an alarm If neither the
hard wired or communicated space temperature are valid, the equipment will shut down
AI2; Space Temperature Local Setpoint
Space Temperature Local Setpoint AI2 functions as the local (hard wired) space temperature
setpoint input for applications utilizing a Trane space temperature sensor with a temperature
setpoint thumbwheel or digital setpoint input A setpoint value communicated by means of a
BACnet link, can be used for controllers operating on a BAS If both hard wired and
communicated setpoint values are present, and in service, the UC400 Controller uses the
communicated value
In addition, the controller can be configured to use the local (hard wired) input value instead of
the communicated value using the Tracer TU service tool If neither a hard wired nor a
communicated setpoint value is present, the controller uses the space temperature setpoint
default analog value, which is configured using the Tracer TU service tool If a local setpoint
value is not valid or not present, the controller generates a Space Temperature Setpoint Local
alarm
AI3; Local Fan Mode Input
Local Fan Mode Input AI3 functions as the local (hard wired) fan mode switch input for
applications using the Trane space temperature sensor with a fan mode switch option The
various fan mode switch positions (OFF, LOW, MEDIUM, HIGH, AUTO) provide different
resistances that are interpreted by the UC400 Controller
NNoottee:: The local fan speed switch can be disabled by taking out of ser ice the multi-state point,
supply fan speed local and setting the alue for each to AUTO.
A communicated fan mode request by means of the BACnet communications link, can be used
for controllers operating on a BAS If both hard wired and communicated fan mode values are
present and in service, the UC400 Controller uses the communicated value However, the
controller can be configured to use the local (hard wired) input value instead of the
communicated BAS value The supply fan speed source (local or BAS) can be selected on the
Tracer TU Setup Parameters page If neither a hard wired nor a communicated fan mode value is
present, the controller recognizes the fan mode value as AUTO and operates according to the
default configuration If a valid hard wired or communicated fan mode value is established, and
then is no longer present, the controller generates a Supply Fan Speed Local alarm
AI4; Discharge Air Temperature Sensor
Discharge Air Temperature Sensor AI4 functions as the local discharge air temperature input
The UC400 Controller receives the temperature as a resistance signal from a 10 kΩ thermistor
wired to analog input AI4 The thermistor is typically located downstream from all unit heating
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss

16 BAS-SVX065E-EN
and cooling coils at the unit discharge area If a discharge air temperature value is invalid, or is
not present, the controller generates a Discharge Air Temp Failure alarm
AI5; Entering Water Temperature
Entering Water Temperature AI5 functions as the local (hard wired) entering water temperature
input An entering water temperature communicated by means of the BACnet communications
link (AV/4 Source Water Temperature BAS), can be used for UC400 Controller controllers
operating on a BAS If both hard wired and communicated entering water temperature values are
present, and in service, the controller uses the communicated value If a hard wired nor a
communicated entering water temperature value is not valid, the controller generates an
Entering Water Temperature Failure alarm
Universal Inputs
The UC400 Controller has two (2) universal inputs
UI1; Leaving Water Temperature
The UI1 analog input functions as the local (hard wired) leaving water temperature input The
unit can be configured to Alarm upon low leaving water temperatures
UI2; elative Humidity or CO2Sensor
RReellaattiivvee HHuummiiddiittyy:: the pre-configured unit requires a 4-20 mA analog input corresponding
linearly to a 0%-100% relative humidity
CCOO22 SSeennssoorr IInnppuutt:: the pre-configured unit requires a 4-20 mA analog input corresponding
linearly to 0-2000 ppm Factory applications do not support CO2control Instead, they only
monitor the status of the sensor input
Pressure Inputs
The UC400 Controller controller has two (2) pressure inputs
NNoottee:: PI2 has no connection.
PI1; Condensate Overflow
Condensate overflow prevents the condensate drain pan from overflowing and causing water
damage to the building If PI1 is wired to a condensate overflow switch, and the level of
condensate reaches the trip point, the UC400 Controller detects the condition and generate a
Condensate Overflow diagnostic
Wiring equirements
The following table lists the required UC400 Controller inputs for proper minimum operation of
all applications The following wiring diagrams are separated to show first the UC400 and then
the UC400–B
Table 7. equired inputs
Function Input source Related information
24 Vac Power Terminals: Ground, 24 Vac
For more details on power wiring
requirements, refer to the Tracer UC400
Controller Programmable Controller
Installation, Operation, and Maintenance
Manual, BAS-SVX20.
Space Temperature Local. Terminals: AI1, Ground AI1; Space Temperature
Entering Water Temperature
(Required Only for Units With
Auto-changeover.
Terminal: AI5 or communicated AI5; Entering Water Temperature
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss

BAS-SVX065E-EN 17
UC400 Wiring Diagrams
Figure 2. Common input/sensor connections (Trane EX units only)
VAC
24
XFRM VAC
24
VAC
24
BI 1 BI 2 BI 3
LINK IMC
+
24
VDC
BI4
AO1 BI
5
AO2 UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
IM
C
1
IM
C
1
4
3
2
VAC
24
XFRM VAC
24
VAC
24
BI
1
BI
2
BI
3
LINK IMC
+
24
VDC
BI4
AO1 BI
5
AO2 UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
CNCNO BO3 CNCNO BO2 CNCNO BO1 RELAYS
ADDRESS
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5BO4
A BB
TX
RX
LINK IMC
SERVI
C
E
SERVICE TOOL
CONNECT AC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
BO1 BO2 BO3 BO4 BO5 BO6 BO7 BO8 BO9
1
2
3
4
5
6
7
8
9
IM
C
1
IM
C
1
3
4
5
6
7
1
2
3
4
5
6
7
8
9
8
9
Ground 24 Vac
Occupancy
(Open Occu)
Compressor
Lockout
Status
Defrost
Comm In
Comm Out
Supply Fan Speed
Space Temp Setpoint
Space Temp
Ground
Pressure Inputs
*Condensate
Overflow
*Entering
Water Temp
*Relative
Humidity
Sensor
Fan
Status
ECM Fan
Motor
Space
Temp
Sensor
Two-Tier
Terminal
Connections
Leaving
Water Temp
Sensor
Disc harge
Air Temp
Zone Sensor Service
Tool Connection
Auxiliary 24 Vdc
Output
Asterisks (*) Shown Above
• UI1 Relative Humidity Sensor
can be used with dehumidifying
unit instead of a BAS-
communicated valve.
•AI5 Entering Water Temp
Sensor used for auto-
changeover units.
•P1 Condensate Overflow
prevents the condensate drain
from overflowing and
causing water damage to
the building.
Note: BI4 Frost Detect Input used
to detect freeze conditions
that produce frost on the coil
surface.
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss

18 BAS-SVX065E-EN
Figure 3. 2–position ventilation economizer (Trane EX units only)
VAC
24
XFRM VAC
24
VAC
24
BI
1
BI
2
BI
3
LINK IMC
+
24
VDC
BI
4
AO1
BI
5
AO2 UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
CNCNO BO3 CNCNO BO2 CNCNO BO1 RELAYS
ADDRESS
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5BO4
A BB
TX
RX
LINK IMC
SERVI
C
E
SERVICE TOOL
CONNECT AC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
BO1 BO2 BO3 BO4 BO5 BO6 BO7 BO8 BO9
1
2
3
4
5
6
7
8
9
IM
C
1
IM
C
1
3
4
5
6
7
1
2
3
4
5
6
7
8
9
8
9
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5BO4
A BB
CONNECTAC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
Single-Tier
Terminal
Connections
Ground
To 24 Vac
Supply Compressor
Command
Waterside
Economizer
Fan
Start/Stop
(EX/DX Units)
Hot Gas
Reheat/
Elec Heat
Reversing
Valve
Isolation
Valve
Outdoor
Air Damper
NOTES:
• BO5 is used for compressor stage 2 on DX units and BO4 is for compressor stage 1 on DX units.
• When Hot Gas Reheat and Electric Heat are present on the same WSHP, Electric Heat will be moved to BO1 on XM32.
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss

BAS-SVX065E-EN 19
Figure 4. Common input/sensor connections (GE units only)
VAC
24
XFRM VAC
24
VAC
24
BI 1 BI 2 BI 3
LINK IMC
+
24
VDC
BI4
AO1 BI
5
AO2 UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
IM
C
1
IM
C
1
4
3
2
VAC
24
XFRM VAC
24
VAC
24
BI
1
BI
2
BI
3
LINK IMC
+
24
VDC
BI4
AO1 BI
5
AO2 UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
CNCNO BO3 CNCNO BO2 CNCNO BO1 RELAYS
ADDRESS
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5BO4
A BB
TX
RX
LINK IMC
SERVI
C
E
SERVICE TOOL
CONNECT AC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
BO1 BO2 BO3 BO4 BO5 BO6 BO7 BO8 BO9
1
2
3
4
5
6
7
8
9
IM
C
1
IM
C
1
3
4
5
6
7
1
2
3
4
5
6
7
8
9
8
9
Asterisks (*) Shown Above
• BI4 Frost Detect Input used
to detect freeze conditions
that produce frost on the coil
surface.
• UI1 Relative Humidity Sensor
can be used with dehumidifying
unit instead of a BAS-
communicated valve.
•AI5 Entering Water Temp
Sensor used for auto-
changeover units.
•P1 Condensate Overflow
prevents the condensate drain
from overflowing and
causing water damage to
the building.
Ground 24 Vac
Occupancy
Compressor
1 Lockout
Compressor
2 Lockout
*In Defrost
Comm In
Comm Out
Supply Fan Speed
Space Temp Setpoint
Space Temp
Ground
Pressure Inputs
*Condensate
Overflow
*Entering
Water Temp
*Relative
Humidity
Sensor
Supply
Fan
Status
Space
Temp
Sensor
Two-Tier
Terminal
Connections
Leaving
Water Temp
Sensor
Discharge
Air Temp
Zone Sensor Service
Tool Connection
Auxiliary 24 Vdc
Output
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss

20 BAS-SVX065E-EN
Figure 5. 2–position ventilation economizer (GE units only)
VAC
24
XFRM VAC
24
VAC
24
BI
1
BI
2
BI
3
LINK IMC
+
24
VDC
BI
4
AO1
BI
5
AO2 UI
1
UI
2
AI
3
AI
2
AI
1
AI
4
AI
5
P
1
P
2
CNCNO BO3 CNCNO BO2 CNCNO BO1 RELAYS
ADDRESS
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5BO4
A BB
TX
RX
LINK IMC
SERVI
C
E
SERVICE TOOL
CONNECT AC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
BO1 BO2 BO3 BO4 BO5 BO6 BO7 BO8 BO9
1
2
3
4
5
6
7
8
9
IM
C
1
IM
C
1
3
4
5
6
7
1
2
3
4
5
6
7
8
9
8
9
TRIAC SUPPLY TRIACS
A
BO9BO8BO7BO6BO5BO4
A BB
CONNECTAC POWER TO THE TRAIC SUPPLY TO POWER THE TRIACS
Single-Tier
Terminal
Connections
Ground
Low
24 Vac
High
Fan Output
To 24 Vac
Supply
Compressor 1 Command
Compressor 2 Command
Waterside
Economizer
Hot Gas
Reheat/Elec Heat
Reversing Valve
Isolation Valve
Outdoor Air Damper
NOTE:
When Hot Gas Reheat and Electric Heat are present on the same WSHP, Electric Heat will be moved to BO1 on XM32.
TTyyppiiccaall AApppplliiccaattiioonnss aanndd TTeerrmmiinnaattiioonnss