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Table 17 — 38AUD 12-14 Electrical Data with Powered Convenience Outlet
NOMINAL
NUMBER
POWER
UNIT SIZE
OF
SUPPLY
STAGES
V-Ph-Hz
3
575-3-60
38AUDT12
3
208/230-3-60
3
460-3-60
3
575-3-60
38AUDT14
3
208/230-3-60
3
460-3-60
NOTE(S):
a. See Legend and Notes for Tables 14-17
LEGEND AND NOTES FOR TABLES 14-17
LEGEND
FLA
— Full Load Amps
LRA
— Locked Rotor Amps
MOCP — Maximum Over Current Protection
NEC
— National Electrical Code
RLA
— Rated Load Amps
NOTES
1. The MCA and Fuse values are calculated in accordance with the
NEC Article 440.
2. Motor RLA and LRA values are established in accordance with
Underwriters Laboratories (UL) Standard 1995.
3. The 575-v units are UL, Canada-listed only.
4. Unbalanced 3-Phase Supply Voltage. Never operate a motor
where a phase imbalance in supply voltage is greater than 2%.
Use the following formula to determine the percentage of voltage
imbalance.
max voltage deviation from average voltage
% Voltage
= 100 x
Imbalance
Example: Supply voltage is 230-3-60
AB = 224 v
A
B
C
BC = 231 v
AC = 226 v
MOTOR
(224 + 231 + 226)
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 = 100x
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 immediately.
Step 8 — Wind Baffles for Low Ambient Control
Units with low ambient control (either as a factory-installed
option or a field-installed accessory) require the addition of wind
baffles to ensure full range low ambient operation. Material data
and dimensions for wind baffles are included in the Appendix C
section, Low Ambient Control, starting on page 49. Fabricate the
wind baffles and mount per instructions.
VOLTAGE
RANGE
No. 1
Min
Max
RLA
518
633
6.4
187
253
16.4
414
506
6.8
518
633
6.6
187
253
17.5
414
506
8.4
average voltage
681
=
=
227
3
3
4
= 1.78%
227
COMPRESSOR
No. 2
LRA
RLA
LRA
Qty
48
5.8
39
2
110
15.6
110
2
55
7.7
52
2
55
6.6
55
2
136
19.6
136
2
66
8.2
66
2
IMPORTANT: Before beginning Pre-Start-Up or Start-Up,
review Start-Up Checklist at the back of this book. The Check-
list assures proper start-up of a unit and provides a record of
unit condition, application requirements, system information,
and operation at initial start-up.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Do not attempt to start the condensing unit, even momentarily,
until the following steps have been completed. Compressor
damage may result.
System Check
1.
The electrical power source must agree with the unit's name-
plate rating.
2.
Check all air handler(s) and other equipment auxiliary com-
ponents. Consult the manufacturer's instructions regarding
any other equipment connected to the condensing unit. If the
unit has field-installed accessories, be sure all are properly
installed and correctly wired. If used, the airflow switch must
be properly installed.
3.
Check tightness of all electrical connections.
4.
Be sure liquid line and low side of the system are properly
leak checked and dehydrated.
5.
Be sure the unit is properly charged. See "Preliminary
Charge", below.
6.
Open the liquid line and suction line service valves.
7.
The crankcase heater must be firmly attached to the compres-
sor crankcase. Be sure the crankcase is warm (heater must be
on for 24 hours before starting compressor).
Turn On Crankcase Heater
Turn on the crankcase heater for 24 hours before starting the unit
to be sure all the refrigerant is out of the oil. To energize the crank-
case heater, proceed as follows:
1.
Set the space thermostat set point above the space tempera-
ture so there is no demand for cooling.
2.
Close the field disconnect.
Preliminary Charge
Before starting the unit, charge liquid refrigerant into the high side
of the system through the liquid service valve. The amount of re-
frigerant added must be at least 80% of the operating charge listed
in the Physical Data table (Tables 5 and 6). Allow high and low
18
a
OFM
POWER SUPPLY
Fuse or
FLA (ea)
MCA
HACR
Brkr
0.7
17
20
1.5
44/44
60/60
0.8
21
25
0.7
18
20
1.5
50/50
60/60
0.8
23
30
PRE-START-UP
CAUTION
DISCONNECT SIZE
FLA
LRA
18
93
46/46
231/231
21
113
19
116
52/52
283/283
23
138
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