Electrical data, 581a155,180, Electrical data -246 – Bryant 581A/B User Manual
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ELECTRICAL DATA — 581A (cont)
ELECTRICAL DATA — 581A155,180
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 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%.
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
UNIT
581A
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*
155
(Standard
IFM)
208/230
187
253
20.7
156
20.7
156
3
0.5
1.70
2.9
8.8/ 8.4
—
—
0.57
60/60
80/80
4.6
18.8
0.57
65/65
80/80
460
414
506
10.0
75
10.0
75
3
0.5
0.80
2.9
4.2
—
—
0.30
29
35
2.3
6.0
0.30
31
40
575
518
633
8.2
54
8.2
54
3
0.5
0.75
3.0
3.9
—
—
0.57
25
30
2.1
4.8
0.57
27
30
155
(Optional
IFM)
208/230
187
253
20.7
156
20.7
156
3
0.5
1.70
3.7 10.5/11.0
—
—
0.57
62/63
80/80
4.6
18.8
0.57
67/67
80/80
460
414
506
10.0
75
10.0
75
3
0.5
0.80
3.7
4.8
—
—
0.30
30
35
2.3
6.0
0.30
32
40
180
208/230
187
253
32.1
195
20.7
156
3
0.5
1.70
5.0 15.8/15.8
—
—
0.57
82/82
110/110
4.6
18.8
0.57
86/86
110/110
460
414
506
16.4
95
10.0
75
3
0.5
0.80
5.0
7.9
—
—
0.30
41
50
2.3
6.0
0.30
43
50
575
518
633
12.0
80
8.2
54
3
0.5
0.75
5.0
6.0
—
—
0.57
31
40
2.1
4.8
0.57
34
45
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
7
457
581
A155
-3
00