Utility Connections; Main Power And Control Wiring - Trane TR-OHS RCU Series Installation, Operation And Maintenance Manual

Utility Connections

WARNING
Proper Field Wiring and Grounding
Required!
Failure to follow code could result in death or serious
injury. All field wiring MUST be performed by qualified
personnel. Improperly installed and grounded field
wiring poses FIRE and ELECTROCUTION hazards. To
avoid these hazards, you MUST follow requirements for
field wiring installation and grounding as described in
NEC and your local/state/national electrical codes.

Main Power and Control Wiring

Systems equipped with an RCU require field wiring
between the RCU and the system controller (refer to the
below figure). The RCU unit is provided with main power
and control terminal positions for connection of the field-
wiring (supplied by others). It is important to identify the
options that were purchased with the unit in order to
confirm which field connections are required. Refer to the
electrical drawing supplied with the unit to determine the
total number of interconnecting conductors required for
the system.
Figure 5. RCU field wiring
Main Power Supply
Control Wires
(Quantity varies)
The RCU is available in the following voltage
configurations:
• 208-230 Vac 1-phase
• 208-230 Vac 3-phase
• 277 Vac 1-phase
• 460 Vac 3-phase
• 575 Vac 3-phase
Verify that the main power supply coincides with the
voltage, phase and frequency information specified on the
system nameplate. The supply voltage measured at the
unit must be within ±10% of the voltage specified on the
nameplate (refer to the below figure). The nameplate also
provides the full load amps (FLA), the current that the unit
SS-SVX004C-EN
L1
L2
L3
Remote Condensing Unit
Interconnecting Field Wiring
(to be installed in accordance
with NFPA 70, N.E.C.
will draw under full design load, the minimum circuit
ampacity (MCA) for wire sizing, and the maximum fuse or
HACR (Heating, Air Conditioning, Refrigeration) breaker
size (MAX FUSE/CKT BKR) for circuit protection. The unit's
nameplate is located inside the cabinet within the
electrical box.
Pilot hole openings for the conduit are located in the side
of the electric box. A label stating MAIN POWER INPUT is
in close proximity. The main power wires are terminated
at the line side of the service disconnect switch located
within the electric box. A separate equipment ground lug
is provided within the electrical box for termination of the
earth ground wire.
The installer must also wire control conductors from the
terminal board within the RCU unit to the system
controller. The number of control conductors needed will
vary depending on the type of control being used with the
equipment. Refer to the electrical drawing supplied with
the unit to determine the correct quantity of control
conductors needed and for the proper wire terminations.
Installation
13