Step 5 - Make Electrical Connections - Carrier 50TFQ004 Installation, Start-Up And Service Instructions Manual

Step 5 — Make Electrical Connections
Unit cabinet must have an uninterrupted, unbroken electri-
cal ground to minimize the possibility of personal injury if
an electrical fault should occur. This ground may consist of
electrical wire connected to unit ground lug in control com-
partment, or conduit approved for electrical ground when
installed in accordance with NEC (National Electrical
Code), ANSI/NFPA (American National Standards Insti-
tute/National Fire Protection Association) 70 (latest year),
and local electrical codes. Failure to follow this warning
could result in the installer being liable for personal injury
of others.
FIELD POWER SUPPLY — All units except 208/230-v
units are factory wired for the voltage shown on the nameplate.
If the 208/230-v unit will be connected to a 208-v power sup-
ply, the transformer must be rewired by disconnecting the
black wire from the 230-v terminal on the transformer and
connecting it to the 200-v terminal from the transformer.
Refer to the unit label diagram for additional information.
Pigtails are provided for field wire connections. Use factory-
supplied splices or a UL (Underwriters' Laboratories)
approved copper/aluminum connector.
When installing units, provide a disconnect per the
NEC. All field wiring must comply with the NEC and local
requirements.
Install field wiring as follows:
1. Install conduit through the side panel openings. For units
without electric heat, install conduit between the discon-
nect and control box.
2. Install power lines to terminal connections as shown in
Fig. 7.
3. For units with electric heat, refer to Table 2 and Accessory
Electric Heat Installation Instructions.
During operation, voltage to compressor terminals must be
within the range indicated on the unit nameplate (also see
Tables 3A and 3B). On 3-phase units, voltages between phases
must be balanced within 2% and the current within 10%. Use
the formula shown in Tables 3A and 3B and Note 2, on page 12
to determine the percentage of voltage imbalance. Operation
on improper line voltage or excessive phase imbalance consti-
tutes abuse and may cause damage to electrical components.
Such operation invalidates any applicable Carrier warranty.
NOTE: If the unit is mounted on a roof curb and the electrical
power will be run up "thru-the-bottom," be sure to choose the
proper accessory kit shown in Fig. 1. This kit, available from
your local distributor, ensures a reliable watertight connection.
Refer to the thru-the-bottom accessory installation instructions
for information on wiring the unit.
7