19
Table 5 — Electrical Data (Units W ith Optional Convenience Outlet) (cont)
UNIT
SIZE
50PG
NOMINAL
VOLTAGE
(3 Ph,
60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM
ELECTRIC
HEAT
IFM
POWER
EXHAUST
POWER SUPPLY
POWER SUPPLY
WITH OPTIONAL
HACR BREAKER
DISCONNECT
SIZE
No. 1 No. 2 No. 3
Min Max RLA LRA RLA LRA RLA LRA Qty Hp
FLA
(ea)
kW FLA Hp FLA Qty Hp
FLA
(ea)
MCA MOCP* MCA MOCP FLA
20
575 518 633 12.8 83 12.8 83 — — 4 0.25 0.7
— —
5 6.1
— — — 41 50 41 50 43
2 1 2.4 46 50 46 50 49
7.5 9
— — — 44 50 44 50 46
2 1 2.4 48 60 48 60 52
10 11
— — — 46 50 46 50 49
2 1 2.4 50 60 50 60 54
24.8 24
5 6.1
— — — 41 50 41 50 43
2 1 2.4 47 50 47 50 49
7.5 9
— — — 45 50 45 50 46
2 1 2.4 51 60 51 60 52
10 11
— — — 48 50 48 50 49
2 1 2.4 54 60 54 60 54
48.3 46
5 6.1
— — — 69 70 69 70 63
2 1 2.4 75 80 75 80 69
7.5 9
— — — 73 80 73 80 67
2 1 2.4 79 80 79 80 72
10 11
— — — 75 80 75 80 69
2 1 2.4 81 90 81 90 75
78 75
5 6.1
— — — 86 100 86 100 97
2 1 2.4 92 100 92 100 102
7.5 9
— — — 90 100 90 100 100
2 1 2.4 96 100 96 100 106
10 11
— — — 93 100 93 100 102
2 1 2.4 99 100 99 100 108
Electric Heat Branch Circuit For 208/240-V 75-kW Electric Heat{
UNIT
SIZE
50PG
NOMINAL
VOLTAGE
(3 Ph,
60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM
ELECTRIC
HEAT
IFM
POWER
EXHAUST
POWER SUPPLY
POWER SUPPLY
WITH OPTIONAL
HACR BREAKER
DISCONNECT
SIZE
No. 1 No. 2 No. 3
Min Max RLA LRA RLA LRA RLA LRA Qty Hp
FLA
(ea)
kW FLA Hp FLA Qty Hp
FLA
(ea)
MCA MOCP* MCA MOCP FLA
20
208/240 187 253 NA NA NA NA NA NA NA NA NA 56/75 156/180 NA NA NA NA NA 156/180 175/200 180/180 200/200 179/207
Feeder Circuit For 208/230-V Unit With 75-kW Electric Heat{
UNIT
SIZE
50PG
NOMINAL
VOLTAGE
(3 Ph,
60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM
ELECTRIC
HEAT
IFM
POWER
EXHAUST
POWER SUPPLY
POWER SUPPLY
WITH OPTIONAL
HACR BREAKER
DISCONNECT
SIZE
No. 1 No. 2 No. 3
Min Max RLA LRA RLA LRA RLA LRA Qty Hp
FLA
(ea)
kW FLA Hp FLA Qty Hp
FLA
(ea)
MCA MOCP* MCA MOCP FLA
20
208/240 187 253 28.2 208 28.2 208 — — 4 0.25 1.5 56/75 156/180
3.7 10.6/ 9.6
— — — 176/198 200/225 198/198 200/225 197/224
2 1 5.9 190/213 200/225 213/213 225/225 211/237
5 16.7/15.2
— — — 183/205 200/225 205/205 225/225 204/230
2 1 5.9 198/220 200/225 220/220 225/225 218/244
7.5 24.2/22
— — — 193/214 200/225 214/214 225/225 213/238
2 1 5.9 207/229 225/250 229/229 250/250 227/252
10 30.8/28
— — — 201/221 225/225 221/221 225/225 221/245
2 1 5.9 216/236 225/250 236/236 250/250 234/259
LEGEND
FLA --- F u l l L o a d A m p s
HACR --- Heating, Air Conditioning and Refrigeration
IFM --- Indoor (Evaporator) Fan Motor
LRA --- L o c k e d R o t o r A m p s
MCA --- Minimum Circuit Amps
MOCP --- Maximum Overcurrent Protection
NEC --- National Electrical Code
OFM --- Outdoor (Condenser) Fan Motor
RLA --- RatedLoadAmps
* Fuse or HACR circuit breaker.
{ 208/230 v 75---kW Electric Heat units must use dual--- point wiring. The main table lists the
branch circuit values for the refrigeration part of the system. The following two tables list the
branch circuit values for the electric heat and values for a feeder circuit for both branch
circuits.
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equip-
ment (refer to NEC Articles 430 and 440), the overcurrent protective device for the
unit shall be fuse or HACR breaker. Canadian units may be fuse or circuit breaker.
2. 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.
% Voltage Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 460-3-60
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage =
452 + 464 + 455
3
1371
3
=
457
=
Determine maximum deviation from average voltage.
(AB) 457 – 452 = 5 v
(BC) 464 – 457 = 7 v
(AC) 457 – 455 = 2 v
Maximum deviation is 7 v.
Determine percent of voltage imbalance.
% Voltage Imbalance = 100 x
7
457
= 1.53%
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.
3. The 75-kW 208/240-v electric heat can be factory installed but it must be wired
separately in the field.
4. The convenience outlet full load amps (FLA) are 5, 3 and 3 for 208/230, 460, 575-v
units, respectively.
5. The FLA load amps provided in the table for electric heaters are based on 208/240,
480 and 600 v.
6. MCA calculation for 50PG units with electric heaters over 50 kW is = 1.25 x (IFM +
P ower Exhaust + Convenience Outlet FLA amps) + 1.00 x (Electric Heater FLA).
50PG20 ---28
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