Carrier 50TJ016-028 User Manual
Page 10
10
Table 2 — Electrical Data (cont)
LEGEND
*Heater capacity (kW) is based on heater voltage of 208 v, 240 v,
380 v, 480 v, and 575 v. Heaters are rated at 240 v, 380 v, 480 v, or
600 v. If power distribution voltage to unit varies from rated heater
voltage, heater kW will vary accordingly.
†Fuse or HACR circuit breaker.
**Heaters are field installed only.
NOTES:
1. In compliance with NEC requirements for multimotor and combi-
nation load equipment (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 volt-
age is greater than 2%. Use the following formula to determine
the percent of voltage imbalance.
% Voltage Imbalance
Example: Supply voltage is 460-3-60.
AB = 452 v
BC = 464 v
AC = 455 v
= 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
= 1.53%
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
3. MCA calculation for units with electric heaters over 50 kW =
(1.25 x IFM amps) + (1.00 x heater FLA).
UNIT
50TJ
NOMINAL
VOLTAGE
(3 Ph,
60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM
IFM
POWER
EXHAUST
ELECTRIC
HEAT*
POWER
SUPPLY
No. 1
No. 2
Min Max RLA LRA RLA LRA Qty Hp FLA (ea) Hp
FLA
FLA LRA
kW
FLA
MCA
MOCP†
028
(25 Tons)
208/230
187
253
41.0 350 37.8 239
2
1
6.6
10.0 28.0/28.0
—
—
—
—
130/130 150/150
4.6
18.8
—
—
135/135 175/175
—
—
26/34
71/82
130/138 150/150
4.6
18.8
26/34
71/82
135/143 175/175
—
—
42/56
117/135 181/170 200/175
4.6
18.8
42/56
117/135 187/176 200/200
—
-
56/75** 156/180 191/215 200/225
4.6
18.8 56/75** 156/180 197/221 200/225
380
342
418
21.8 151 21.2 145
2
1
3.9
10.0
17.0
—
—
—
—
73
90
2.3
6.0
—
—
76
90
—
—
20
30
73
90
2.3
6.0
20
30
76
90
—
—
35
52
87
90
2.3
6.0
35
52
90
90
460
414
508
21.8 158 17.2 125
2
1
2.8
10.0
14.6
—
—
—
—
66
80
2.3
6.0
—
—
68
80
—
—
32
39
67
80
2.3
6.0
32
39
70
80
—
—
55
66
84
90
2.3
6.0
55
66
87
100
—
—
80**
96
114
125
2.3
6.0
80**
96
117
125
575
518
633
17.3 125 12.4
80
2
1
3.4
10.0
13.0
—
—
—
—
54
70
2.1
4.8
—
—
56
70
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
= 100 x
max voltage deviation from average voltage
average voltage
Average Voltage =
452 + 464 + 455
3
=
1371
3
IMPORTANT: If the supply voltage phase imbalance is
more than 2%, contact your local electric utility company
immediately.
7
457