Electrical data – Bryant 581A/B User Manual
Page 166
166
ELECTRICAL DATA
LEGEND
*Fuse or HACR circuit breaker.
NOTES:
1. In compliance with NEC requirements for multimotor and combina-
tion load equipment (refer to NEC Articles 430 and 440), the over-
current 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 per-
cent voltage imbalance.
% Voltage Imbalance
EXAMPLE: Supply voltage is 460-3-60.
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 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.
UNIT
579F
NOMINAL
VOLTAGE
(3 Ph, 60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM
IFM
POWER
EXHAUST
COMBUSTION
FAN MOTOR
POWER
SUPPLY
No. 1
No. 2
Min Max RLA LRA RLA LRA Qty Hp FLA
(ea)
Hp
FLA
FLA LRA
FLA
MCA
MOCP*
180
(15 Tons)
208/230
187
253
28.8 195
28.8
195
3
0.5
1.7
3.7
10.5/11.0
—
—
0.57
81/81
100/100
4.6
18.8
0.57
85/86
110/110
460
414
508
14.7
95
14.7
95
3
0.5
0.8
3.7
4.8
—
—
0.30
40
50
2.3
6.0
0.30
43
50
575
518
633
10.8
80
10.8
80
3
0.5
0.8
3.0
3.9
—
—
0.57
30
40
2.1
4.8
0.57
32
40
216
(18 Tons)
208/230
187
253
30.1 225
28.8
195
3
0.5
1.7
5.0
15.8/15.8
—
—
0.57
87/87
110/110
4.6
18.8
0.57
92/92
110/110
460
414
508
15.5 114
14.7
95
3
0.5
0.8
5.0
7.9
—
—
0.30
44
50
2.3
6.0
0.30
47
60
575
518
633
12.1
80
10.8
80
3
0.5
0.8
5.0
6.0
—
—
0.57
34
40
2.1
4.8
0.57
36
40
240
(20 Tons)
208/230
187
253
37.8 239
30.1
225
2
1
6.6
7.5
25.0/25.0
—
—
0.57
116/116 150/150
4.6
18.8
0.57
120/120 150/150
460
414
508
17.2 125
15.5
114
2
1
3.3
7.5
13.0
—
—
0.30
57
70
2.3
6.0
0.30
59
70
575
518
633
12.4
80
12.1
80
2
1
3.4
7.5
10.0
—
—
0.57
44
50
2.1
4.8
0.57
46
50
300
(25 Tons)
208/230
187
253
41.0 350
37.8
239
2
1
6.6
10.0 28.0/28.0
—
—
0.57
130/130 150/150
4.6
18.8
0.57
135/135 175/175
460
414
508
21.8 158
17.2
125
2
1
3.3
10.0
14.6
—
—
0.30
66
80
2.3
6.0
0.30
68
80
575
518
633
17.3 125
12.4
80
2
1
3.4
10.0
13.0
—
—
0.57
54
70
2.1
4.8
0.57
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
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage = 452 + 464 + 455
3
=
1371
3
= 457
% Voltage Imbalance = 100 x
7
457
= 1.53%
0TF
Q004
-0
12
5
7
9
F
18
0-
300