Units Without Factory-Installed Non- Fused Disconnect Or Hacr - Carrier WeatherMaster Series Installation Instructions Manual

Fig. 22 — HACR Enclosure Location
Fig. 23 — HACR Handle and Shaft Assembly
UNITS WITHOUT FACTORY-INSTALLED NON-FUSED
DISCONNECT OR HACR
When installing units, provide a disconnect switch per
NEC (National Electrical Code) of adequate size. Disconnect
sizing data is provided on the unit informative plate. Locate
on unit cabinet or within sight of the unit per national or local
codes. Do not cover unit informative plate if mounting the
disconnect on the unit cabinet.
ALL UNITS
All field wiring must comply with NEC and all local
codes. Size wire based on MCA (Minimum Circuit Amps) on
the unit informative plate. See Fig. 18 and the unit label dia-
gram for power wiring connections to the unit power terminal
blocks and equipment ground. Maximum wire size is #2ga
AWG (copper only) per pole on contactors, #2ga AWG (cop-
per only) per pole on optional disconnect or HACR, and 4/0
AWG (copper only) per pole on terminal or fuse block on
units with single point box. See Fig. 18 and unit label dia-
gram for field power wiring connections.
Provide a ground fault and short circuit over-current pro-
tection device (fuse or breaker) per NEC Article 440 (or local
codes). Refer to unit informative data plate for MOCP (Maxi-
mum Over-Current Protection) device size.
NOTE: Units ordered with factory installed HACR do not need
an additional ground fault and short circuit over-current protec-
tive device unless required by local codes.
All field wiring must comply with the NEC and local re-
quirements.
All units except 208/230v units are factory wired for the
voltage shown on the nameplate. If the 208/230v unit is to be
connected to a 208v power supply, the control transformer
must be rewired by removing the black wire with the
male spade connector from the 230v connection and moving
it to the 200v 1 / -in. male terminal on the primary side of the
4
transformer. Refer to unit label diagram for additional infor-
mation. Field power wires will be connected at line-side pres-
sure lugs on the power terminal block or at factory-installed
option non-fused disconnect. Refer to unit label diagram for
additional information.
Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. On 3-phase
units, voltages between phases must be balanced within 2%
and the current within 10%. Use the formula shown in the ex-
ample below to determine the percent of voltage imbalance.
Operation on improper line voltage or excessive phase imbal-
ance constitutes abuse and may cause damage to electrical
components. Such operation would invalidate any applicable
Carrier warranty.
Example: Supply voltage is 230-3-60
A B C
AB = 224 v
BC = 231 v
AC = 226 v
MOTOR
Average Voltage =
Determine maximum deviation from average voltage.
(AB) 227-224 = 3 v
(BC) 231-227 = 4 v
(AC) 227-226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more
than 2%, contact your local electric utility company immedi-
ately.
Failure to follow this caution may result in equipment dam-
age.
Operation on improper line voltage or excessive phase im-
balance constitutes abuse and may cause damage to electrical
components. Such operation would invalidate any applicable
Carrier warranty.
NOTE: Check all factory and field electrical connections for
tightness.
17
(224 + 231 + 226) 681
=
3 3
4
=
227
CAUTION
1 / -in. fe-
4
= 227
1.78%