548f – Bryant 549B User Manual
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57
ELECTRICAL DATA — 548F (cont)
548F036-120 (UNITS WITHOUT ELECTRICAL CONVENIENCE OUTLET) (cont)
LEGEND
*Heaters are field installed only.
†Used to determine minimum disconnect size per NEC.
**Heater capacity (kW) is based on heater voltage of 208 v, 240 v and 480 v. If
power distribution voltage to unit varies from rated heater voltage, heater kW
will vary accordingly.
††Fuse or HACR circuit breaker.
***Optional disconnect switch is unavailable.
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 percent of voltage
imbalance.
% Voltage Imbalance
Example: Supply voltage is 460-3-60.
AB = 452 v
BC = 464 v
AC = 455 v
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.
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 548F060 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
548F
NOMINAL
V-PH-Hz
IFM
TYPE
VOLTAGE
RANGE
COMPRESSOR
(each)
OFM
FLA
IFM
FLA
ELECTRIC HEAT*
POWER SUPPLY
DISCONNECT
SIZE†
Min
Max
RLA
LRA
Nominal
kW**
FLA
MCA
MOCP
FLA
LRA
072
(6 Tons)
208/230-3-60
STD
187
254
22.7
146.0
1.4
5.8
—
—
35.6/ 35.6
40/ 40††
34/ 34
190/190
4.9/ 6.5
13.6/15.6
52.6/ 55.1
60/ 60††
50/ 52
204/206
7.9/10.5
21.9/25.3
63.0/ 67.2
70/ 70
60/ 63
212/215
12.0/16.0
33.3/38.5
77.2/ 83.7
80/ 90
73/ 79
223/229
15.8/21.0
43.9/50.5
90.5/ 98.7
100/100
85/ 92
234/241***
19.9/26.5
55.2/63.8
104.6/115.3
110/125
98/108
245/254***
HIGH-
STATIC
187
254
22.7
146.0
1.4
7.5
—
—
37.3/ 37.3
40/ 40††
36/ 36
209/209
4.9/ 6.5
13.6/15.6
54.3/ 56.8
60/ 60††
52/ 54
223/225
7.9/10.5
21.9/25.3
64.7/ 68.9
70/ 70
62/ 65
231/234
12.0/16.0
33.3/38.5
78.9/ 85.4
80/ 90
75/ 81
242/248***
15.8/21.0
43.9/50.5
92.2/100.4
100/110
87/ 94
253/260***
19.9/26.5
55.2/63.8
106.3/117.0
110/125
100/110
264/273***
460-3-60
STD
414
508
11.4
73.0
0.7
2.6
—
—
17.6
20††
17
95
6.0
7.2
26.6
30††
25
102
11.5
13.8
34.8
35††
33
109
14.0
16.8
38.6
40††
36
112
23.0
27.7
52.2
60††
49
123
25.5
30.7
55.9
60††
52
126
HIGH-
STATIC
414
508
11.4
73.0
0.7
3.4
—
—
18.4
20††
18
105
6.0
7.2
27.4
30††
26
112
11.5
13.8
35.6
40††
34
118
14.0
16.8
39.4
40††
37
121
23.0
27.7
53.0
60††
50
132
25.5
30.7
56.7
60††
53
135
575-3-60
STD
518
632
9.1
58.4
0.7
2.6
—
—
14.0
15††
14
76
HIGH-
STATIC
518
632
9.1
58.4
0.7
3.4
—
—
14.7
15††
14
84
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
=
457
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
548F