164 electrical data – Bryant DURAPAC 551B User Manual
Page 164
164
ELECTRICAL DATA
ELECTRICAL DATA — 551A155,180
LEGEND
*Heater capacity (kW) is based on heater voltage of 208 v, 240 v, 380 v, 480 v, and 575 v. Heat-
ers are rated at 240 v, 480 v, or 575 v. If power distribution voltage to unit varies from rated
heater voltage, heater kW will vary accordingly. To determine heater capacity at actual unit
voltage, multiply 240 v, 480 v, or 575 v capacity by multipliers found in table on page 150.
†Fuse or HACR circuit breaker.
NOTES:
1.
In compliance with NEC requirements for multimotor and combination load equipment
(refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall be
fuse or HACR breaker. The 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 percent of 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.
= 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.
MCA calculation for 551A155,180 units with electric heaters over 50 kW = (1.25 x IFM
amps) + (1.00 x heater FLA).
UNIT
551A
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†
155
(Standard
IFM)
208/230
187
253
20.7
156
19.3
123
3
0.5
1.7
2.9
8.8/
8.4
—
—
—
—
59/ 59
70/ 70
4.6
18.8
—
—
64/ 63
80/ 80
—
—
14/19
39/ 45
60/ 67
70/ 70
4.6
18.8
14/19
39/ 45
66/ 73
80/ 80
—
—
26/34
71/ 82
100/113
100/125
4.6
18.8
26/34
71/ 82
106/119
110/125
—
—
42/56
117/135
157/146
175/175
4.6
18.8
42/56
117/135
163/151
175/175
460
414
508
10
70
10
62
3
0.5
0.8
2.9 4.2
—
—
—
—
29
35
2.3
6.0
—
—
31
40
—
—
15
18
29
35
2.3
6.0
15
18
31
40
—
—
32
39
54
60
2.3
6.0
32
39
57
60
—
—
55
66
71
80
2.3
6.0
55
66
74
80
155
(Optional
IFM)
208/230
187
253
20.7
156
19.3
123
3
0.5
1.7
3.7
11.0/
10.5
—
—
—
—
61/ 61
80/ 80
4.6
18.8
—
—
65/ 66
80/ 80
—
—
14/19
39/ 45
62/ 70
80/ 80
4.6
18.8
14/19
39/ 45
68/ 76
80/ 80
—
—
26/34
71/ 82
102/116
110/125
4.6
18.8
26/34
71/ 82
108/122
110/125
—
—
42/56
117/135
159/149
175/175
4.6
18.8
42/56
117/135
165/155
175/175
460
414
508
10
70
10
62
3
0.5
0.8
3.7 4.8
—
—
—
—
30
35
2.3
6.0
—
—
32
40
—
—
15
18
30
35
2.3
6.0
15
18
32
40
—
—
32
39
55
60
2.3
6.0
32
39
58
60
—
—
55
66
72
80
2.3
6.0
55
66
75
80
180
208/230
187
253
32.1
195
20.7
156
3
0.5
1.7
5.0
15.8/
15.8
—
—
—
—
82/ 82
110/110
4.6
18.8
—
—
86/ 86
110/110
—
—
26/34
71/ 82
109/122
110/125
4.6
18.8
26/34
71/ 82
114/128
125/150
—
—
42/56
117/135
166/155
175/175
4.6
18.8
42/56
117/135
172/161
175/175
—
—
56/75
156/180
176/200
200/225
4.6
18.8
56/75
156/180
182/206
200/225
460
414
508
16.4
95
10
70
3
0.5
0.8
5.0 7.9
—
—
—
—
41
50
2.3
6.0
—
—
43
50
—
—
32
39
59
60
2.3
6.0
32
39
62
70
—
—
55
66
76
90
2.3
6.0
55
66
79
90
—
—
80
96
106
125
2.3
6.0
80
96
109
125
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
0TF
Q0
04-
01
2
55
1A1
55-
1
8
0