Carrier 50PG20 Installation Instructions Manual page 13

Table 4 — Electrical Data (Units Without Optional Convenience Outlet) (cont)
VOLTAGE
NOMINAL
UNIT
RANGE
VOLTAGE
No. 1
SIZE
(3 Ph,
50PG
60 Hz)
Min Max RLA LRA RLA LRA RLA LRA Qty
20
575 518 633 12.8 83
VOLTAGE
NOMINAL
UNIT
RANGE
VOLTAGE No. 1
SIZE
(3 Ph,
50PG
60 Hz)
Min Max RLA LRA RLA LRA RLA LRA Qty
20
208/240 187 253 NA NA
VOLTAGE
NOMINAL
UNIT
RANGE
VOLTAGE
No. 1
SIZE
(3 Ph,
50PG
60 Hz) Min Max RLA LRA RLA LRA RLA LRA Qty
20
208/240 187 253 28.2 208 28.2 208
LEGEND
FLA
--- Full Load Amps
HACR --- Heating, Air Conditioning and Refrigeration
IFM --- Indoor (Evaporator) Fan Motor
LRA --- Locked Rotor Amps
MCA --- Minimum Circuit Amps
MOCP --- Maximum Overcurrent Protection
NEC
--- National Electrical Code
OFM --- Outdoor (Condenser) Fan Motor
RLA --- Rated Load Amps
* 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
COMPRESSOR
OFM
No. 2 No. 3
FLA
Hp
(ea)
12.8 83 — — 4 0.25 0.7
Electric Heat Branch Circuit For 208/240-V 75-kW Electric Heat{
COMPRESSOR
OFM
No. 2 No. 3
FLA
Hp
(ea)
NA NA NA NA NA NA NA 56/75 156/180 NA
Feeder Circuit For 208/230-V Unit With 75-kW Electric Heat{
COMPRESSOR
OFM
No. 2 No. 3
FLA
Hp
(ea)
— — 4 0.25 1.5
max voltage deviation from average voltage
average voltage
ELECTRIC POWER
IFM
HEAT EXHAUST
kW FLA Hp FLA Qty Hp
— —
5 6.1
2 1
— —
— — 7.5 9
2 1
— —
10 11
2 1
— —
5 6.1
2 1
— —
24.8 24 7.5 9
2 1
— —
10 11
2 1
— —
5 6.1
2 1
— —
48.3 46 7.5 9
2 1
— —
10 11
2 1
— —
5 6.1
2 1
— —
78 75 7.5 9
2 1
— —
10 11
2 1
ELECTRIC POWER
IFM
HEAT EXHAUST
FLA
kW FLA Hp FLA Qty Hp
NA NA NA NA 156/180 175/200 180/180 200/200
ELECTRIC POWER
IFM
HEAT EXHAUST
kW FLA Hp FLA Qty Hp
— —
3.7 10.6/9.6
2 1
— —
5 16.7/15.2
2 1
56/75 156/180
— —
7.5 24.2/22
2 1
— —
10 30.8/28
2 1
Example: Supply voltage is 460-3-60
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage =
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
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 +
Power Exhaust + Convenience Outlet FLA amps) + 1.00 x (Electric Heater FLA).
13
POWER SUPPLY
POWER SUPPLY WITH OPTIONAL
HACR BREAKER
FLA
MCA MOCP* MCA MOCP
(ea)
— 38 50 38 50
2.4 43 50 43 50
— 41 50 41 50
2.4 45 50 45 50
— 43 50 43 50
2.4 47 60 47 60
— 38 50 38 50
2.4 44 50 44 50
— 41 50 41 50
2.4 47 50 47 50
— 44 50 44 50
2.4 50 60 50 60
— 65 70 65 70
2.4 71 80 71 80
— 69 70 69 70
2.4 75 80 75 80
— 71 80 71 80
2.4 77 80 77 80
— 83 90 83 90
2.4 89 100 89 100
— 86 100 86 100
2.4 92 100 92 100
— 89 100 89 100
2.4 95 100 95 100
POWER SUPPLY
WITH OPTIONAL
POWER SUPPLY
HACR BREAKER
MCA MOCP* MCA MOCP
(ea)
POWER SUPPLY
WITH OPTIONAL
POWER SUPPLY
HACR BREAKER
FLA
MCA MOCP* MCA MOCP
(ea)
— 169/192 200/225 192/192 200/225
5.9 184/207 200/225 207/207 225/225
— 177/199 200/225 199/199 200/225
5.9 192/214 200/225 214/214 225/225
— 186/208 200/225 208/208 225/225
5.9 201/222 225/225 222/222 225/225
— 195/215 225/225 215/215 225/225
5.9 209/230 225/250 230/230 250/250
452 + 464 + 455
3
1371
=
3
=
457
7
= 100 x
457
= 1.53%
DISCONNECT
SIZE
FLA
40
45
43
49
45
51
40
45
43
49
45
51
60
65
63
69
66
71
93
99
97
102
99
104
DISCONNECT
SIZE
FLA
179/207
DISCONNECT
SIZE
FLA
192/218
205/232
199/224
212/238
207/232
221/246
215/239
228/253