System Control Circuit Wiring (Field Wiring)
66 CVHH-SVX001A-EN
CWR—Outdoor Option
The outdoor temperature sensor is similar to the unit-
mounted temperature sensors in that it consists of the
sensor probe and the module. A four-wire IPC bus is
connected to the module for 24 Vdc power and the
communications link. Trane recommends mounting the
sensor module within the control panel and the sensor tw o
wire leads be extended and routed to the outdoor
temperature sensor probe sensing location. This ensures
the four-wire IPC bus protection and provides access to the
module for configuration at start-up.
The sensor probe lead wire between the sensor probe and
the module can be separated by cutting the two-wire
probe lead leaving equal lengths of wire on each device:
the sensor probe and the sensor module.
Note: This sensor and module are matched and must
remain together or inaccuracy may occur.
These wires can then be spliced with two 14–18 AWG 600V
wires of sufficient length to reach the desired outdoor
location with a maximum length 304.8 meters (1000 feet).
For AWG/MCM equivalents in mm
2
, refer to
Tab l e 12,
p. 47
. The module four-wire bus must be connected to the
control panel four-wire bus using the Trane-approved
connectors provided.
The sensor will be configured (given its identity and
become functional) at start-up when the Trane service
technician performs the start-up configuration. It will NOT
be operational until that time.
Note: If shielded cable is used to extend the sensor leads,
be sure to cover the shield wire with tape at the
junction box and ground it at the control panel. If
the added length is run in conduit, do not run them
in the same conduit with other circuits carrying 30
or more volts.
Important: Maintain at least 16 cm (6 in.) between low-
voltage (<30V) and high voltage circuits.
Failure to do so could result in electrical
noise that may distort the signals carried by
the low-voltage wiring, including the IPC.
Optional Control and Output Circuits
Install various optional wiring as required by the owner’s
specifications (see
Table 18, p. 63).
Optional Tracer Communication Interface
This control option allows the control panel to exchange
information—such as chiller status and operating set
points—with a Tracer system.
Note: The circuit must be run in separate conduit to
prevent electrical noise interference.
Additional information about the Tracer Communication
interface option is published in the installation and
operation guide that ships with the Tracer.
Unit Start-up/ Commissioning
Important: Start-up must be performed by Trane or an
agent of Trane specifically authorized to
perform start-up and warranty of Trane
®
products. Contractor shall provide Trane (or
an agent of Trane specifically authorized to
perform start-up) with notice of the
scheduled start-up at least two weeks prior
to the scheduled start-up.
Starter Module Configuration
The starter module configuration settings will be checked
(and configured for Remote Starters) during start-up
commissioning.
Note: To configure starter modules, and perform other
starter checks, it is recommended that the line
voltage three-phase power be turned off and
secured (locked out), and then that a separate
source control power (115 Vac) be utilized to power
up the control circuits.
Use the as-built starter schematic to ensure correct fuse
and terminals. Verify that the correct fuse is removed and
that the control circuit connections are correct; then apply
the 115 Vac separate source power to service the controls.
Schematic Wiring Drawings
Please refer to the submittals and drawings that shipped
with the unit. Additional wiring drawings for CenTraVac
chillers are available from your local Trane office.
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