Carrier 48PD05 Installation Instructions Manual page 13

Step 9 -- Make Electrical Connections
Field Power Supply
(For more details, refer to the Controls, Start-Up, Operation, and
Troubleshooting manual).
All 208/230v units are factory wired for 230v power supply. If the
208/230v unit is to be connected to a 208v power supply, the
transformers (TRANI and TRAN2) must be rewired by moving
the black wire with the l/4-in, female quick connector from the
230volt connection and moving to the 200volt l/4-in, male
terminal on the primary side of the transformer.
Refer to unit label diagram for additional information. Leads are
provided for field wire connections. Use UL (Underwriters
Laboratories) approved copper/aluminum connector.
When installing units, provide safety disconnect per NEC
(National Electrical Code) Article 440 or local codes. For
non-fused disconnects, size disconnect according to the sizing data
provided in the electrical data tables. If a fused disconnect is used,
determine the minimum size for the switch based on the disconnect
sizing data provided in the electrical data tables and then
coordinate the disconnect housing size to accommodate the
Maximum Overcurrent Protection (MOCP) device size as marked
on the unit informative plate. (See Table 9 and 10.)
All field wiring must comply with NEC and local codes. Size wire
based on MCA (Minimum Circuit Amps) on the unit informative
plate. See Fig. 12 for power wiring connection to the unit leads and
equipment ground.
Route power and ground lines through control box end panel or
unit basepan (see Fig. 2) to connections as shown on unit wiring
diagram and Fig. 12. Factory leads may be wired directly to the
disconnect.
[]NIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
The correct power phasing is critical to the operation of the
scroll compressors. An incorrect phasing will result in
alarm being generated and compressor operation lockout.
Should this occur, power phase correction must be made to
the incoming power.
ELECTRICALSHOCK HAZARD
Failure to follow this warning could result in personal
iniury or death.
Unit cabinet must have an uninterrupted, unbroken
electrical ground to minimize the possibility of personal
iniury if an electrical fault should occur. This ground may
consist of electrical wire connected to unit ground lug in
control compartment, or conduit approved for electrical
ground when installed in accordance with NEC; ANSI
(American National Standards Institute)/NFPA (National
Fire Protection Association), latest edition, and local
electrical codes. Do not use gas piping as an electrical
ground.
Field wiring must conform to temperature limitations for type "T"
wire. All field wiring must comply with NEC and local
requirements.
Operating voltage to compressor must be within voltage range
indicated on unit nameplate. On 3-phase units, voltages between
phases must be balanced within 2%.
[]nit failure as a result of operation on improper line voltage or
excessive phase imbalance constitutes abuse and may cause
damage to electrical components.
On"
oLU
----I
I FIELD
I
POWER
I WIRING
r
I
I
I-
I
I
POWER
C.A1
EQUIP GND
LEGEND
C.A1 -- Compressor Contactor (A1)
EQUIP -- Equipment
GND -- Ground
NEC -- National Electrical Code
NOTE: The maximum wire size for C.A1 is 2/0.
Fig. 12 - Field Power Wiring Connections
C06237
Field Control
Wiring
Unit can be controlled with a Carrier-approved accessory space
temperature sensor. Install sensor according to the installation
instructions included with accessory. Locate space temperature
sensor on a solid interior wall in the conditioned space to sense
average temperature. The 48PD unit is not compatible with a
conventional YI/WI thermostat.
NOTE: Use 20 AWG (American Wire Gauge) wire to connect the
sensor to the controller. The wire is suitable for distances of up to
500 ft. Use a three-conductor shielded cable for the sensor and
set-point adjustment connections. The standard CCN
communication cable can be used. If the set-point adjustment
(slide bar) is not required, then an unshielded, 18 or 20 AWG
(American Wire Gauge), two-conductor, twisted pair cable can be
used.
Route space temperature sensor cable or equivalent single leads of
colored wire from sensor terminals through conduit into unit to
low-voltage connections as shown on unit label wiring diagram
and in Fig. 13.
g
13