Bryant 549B User Manual
Page 122
122
ELECTRICAL DATA — 549B (cont)
549B036-120 — STANDARD MOTOR UNITS WITH ELECTRICAL CONVENIENCE OUTLET (cont)
LEGEND
*Heater capacity (kW) is based on heater voltage of 208 v, 240 v, or 480 v. If
power distribution voltage to unit varies from rated heater voltage, heater kW
will vary accordingly.
†Heaters are field installed only.
**Fuse or HACR circuit breaker.
††Electrical disconnect cannot be used if electric heater is installed.
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.
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
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%, con-
tact your local electric utility company immediately.
POWER EXHAUST ELECTRICAL DATA
N/A — Not available
NOTE: If a single power source is to be used, size wire to include power exhaust
MCA and MOCP.
Check MCA and MOCP when power exhaust is powered through the unit. Deter-
mine the new MCA including the power exhaust using the following formula:
MCA New = MCA unit only + MCA of Power Exhaust
For example, using a 549B060 unit with MCA = 35.6 and MOCP = 40, with
CRPWREXH030A01 power exhaust.
MCA New = 35.6 amps + 1.6 amps = 37.2 amps
If the new MCA does not exceed the published MOCP, then MOCP would not
change. The MOCP in this example is 40 amps and the MCA New is below 40;
therefore the MOCP is acceptable. If “MCA New” is larger than the published
MOCP, raise the MOCP to the next larger size. In all cases, the MOCP for the
power exhaust should be 15 amps per NEC.
UNIT
549B
NOMINAL
VOLTAGE
(V-Ph-Hz)
VOLTAGE
RANGE
COMPRESSOR
(each)
OFM
(each)
IFM
ELECTRIC HEAT*
POWER SUPPLY
MINIMUM UNIT
DISCONNECT
SIZE
Min
Max
RLA
LRA
FLA
FLA
kW†
FLA
MCA
MOCP
FLA
LRA
090
(7
1
/
2
Tons)
208/230-3-60
187
254
12.4
88.0
1.4
7.5
—
7.8/10.4
12.0/16.0
18.6/24.8
24.0/32.0
31.8/42.4
—
21.7/ 25.0
33.3/ 38.5
51.6/ 59.7
66.6/ 77.0
88.3/102.0
43.0/ 43.0
70.1/ 74.3
84.6/ 91.1
107.5/117.6
126.3/139.3
153.4/170.5
45/ 45**
80/ 80
90/100
110/125
150/150
175/175
46/ 46
71/ 75
84/ 90
105/115
122/134
147/163
247/247
269/272
280/285††
298/307††
313/324††
335/349††
460-3-60
414
508
6.4
44.0
0.7
3.4
—
13.9
16.5
27.8
33.0
41.7
—
16.7
19.8
33.4
39.7
50.2
21.4
42.3
46.1
63.1
71.0
84.1
25**
45**
50**
70
80
90
23
42
46
61
68
80
123
140
143
157
163
174
102
(8
1
/
2
Tons)
208/230-3-60
187
254
13.9
105
1.4
7.5
—
—
46.1/ 46.1
50/ 50**
49/ 49
281/281
7.8/10.4
21.7/ 25.0
73.2/ 77.3
80/ 80
74/ 78
303/306
12.0/16.0
33.3/ 38.5
87.7/ 94.2
90/100
87/ 93
314/319††
18.6/24.8
51.6/ 59.7
110.6/120.7
125/125
108/118
332/341††
24.0/32.0
66.6/ 77.0
129.3/142.3
150/150
126/138
347/358††
31.8/42.4
88.3/102.0
156.5/173.6
175/175
151/166
369/383††
460-3-60
414
508
7.9
55.0
0.7
3.4
—
—
24.5
25**
26
145
13.9
16.7
45.3
50**
45
162
16.5
19.8
49.2
50**
49
165
27.8
33.4
66.2
70
64
179
33.0
39.7
74.1
80
72
185
41.7
50.2
87.2
90
84
196
120
(10 Tons)
208/230-3-60
187
254
19.3
123.0
1.4
10.6
—
7.8/10.4
12.0/16.0
24.0/32.0
31.8/42.4
37.6/50.0
—
21.7/ 25.0
33.3/ 38.5
66.6/ 77.0
88.3/102.0
104.4/120.3
61.6/ 61.6
88.8/ 92.9
103.3/109.8
144.9/157.9
172.0/189.1
192.1/181.9
70/ 70
90/100
110/110
150/175
175/200
200/200
65/ 65
90/ 94
104/110
142/154
167/183
185/204
341/341
363/366††
375/380††
408/418††
430/443††
446/462††
460-3-60
414
508
10.0
62.0
0.7
4.8
—
16.5
27.8
33.0
41.7
50.0
—
19.8
33.4
39.7
50.2
60.1
30.9
55.6
72.6
80.5
93.6
91.0
35**
60**
80
90
100
100
33
55
71
78
90
102
172
191
205
211
222††
232††
FLA
—
Full Load Amps
HACR
—
Heating, Air Conditioning and Refrigeration
IFM
—
Indoor-Fan Motor
LRA
—
Locked Rotor Amps
MCA
—
Minimum Circuit Amps
MOCP
—
Maximum Overcurrent Protection
NEC
—
National Electrical Code
OFM
—
Outdoor-Fan Motor
RLA
—
Rated Load Amps
= 100 x
max voltage deviation from average voltage
average voltage
Average Voltage =
452 + 464 + 455
3
=
1371
3
POWER EXHAUST
PART NO.
MCA
(230 v)
MCA
(460 v)
MCA
(575 v)
MOCP
(for separate
power source)
CRPWREXH021A01
N/A
0.68
N/A
15
CRPWREXH022A01
3.4
N/A
1.32
15
CRPWREXH023A01
N/A
1.4
N/A
15
CRPWREXH028A01
1.7
N/A
0.68
15
CRPWREXH029A01
N/A
0.7
N/A
15
CRPWREXH030A01
1.6
N/A
0.64
15
7
457
549B
, 549
C