Installation
CAH-SVX01A-EN 41
Wiring
Wiring to the unit fan motor must be
provided by the installer and must
comply with all national and local
electrical codes. The installer must
also furnish a fused disconnect
switch in compliance with national
and local electrical codes.
Fan motors also require motor
overload protective devices that are
rated or selected in compliance with
the National Electric Code or
Canadian Electric Code. Specific unit
and motor connection diagrams are
provided on the starter/VFD, if Trane-
provided, or refer to the motor
nameplate.
CAUTION
Use Copper Conductors
Only!
Unit terminals are not designed to
accept other types of conductors.
Failure to use copper conductors
may result in equipment dama
ge.
Figure 41. Transformer plate
Line supply to
transformers
24 Vac to end
devices and
controllers
All direct-digital controllers (DDCs)
are provided with line voltage to
24 Vac control transformers
mounted and wired in the starter or
variable-frequency drive (VFD)
power box transformer plate (see
Figure 41) or 120 to 24 Vac control
transformers mounted and wired in
the auxiliary control panel (see
Figure 42).
Figure 42. Controller with power box
attached
Figure 43. Variable-frequency drive
(VFD)
24 Vac
Line supply
120 Vac
Figure 43 shows a typical VFD power
box.
Note: The valve jack/junction box is
typically located at the air-leaving
side of the coil connection inside
panel. For coils with headers on both
sides of the module, the valve jack is
located at the return connection for
water coils and the supply
connection for steam coils.
ƽ WARNING
Hazardous Voltage with
Capacitors!
Disconnect all electric power,
including remote disconnects and
discharge all motor start/run
capacitors before servicing. Follow
proper lockout/tagout procedures to
ensure the power cannot be
inadvertently energized. For variable
frequency drives or other energy
storing components provided by
Trane or others, refer to the
appropriate manufacturer’s
literature for allowable waiting
periods for discharge of capacitors.
Verify with an appropriate voltmeter
that all capacitors have discharged.
Failure to disconnect power and
discharge capacitors before
servicing could result in death or
serious injury.
To provide field-wiring to units with
DDC controls:
• Provide 120 Vac power to a
transformer in the junction box
provided when a separate circuit
is recommended (see Figure 42).
• Install outside-air sensor and
space sensor, if ordered.
• For valve jack junction box
mounting and wiring detail (see
Figure 43).
CAUTION
Seal the Penetrations!
Seal all penetrations into the unit to
prevent air infiltration during
operation. Failure to do so may
result in equipment damage.