Bryant 581C Manual De Usuario

165

LEGEND

ARI — Air Conditioning and Refrigeration Institute

NOTE: Indoor sound power is available in Bryant’s Electronic Catalog Program (ECAT) for
specific operating parameters.

LEGEND

*The values listed in this table do not include power exhaust. See table at right

for power exhaust requirements.

**Fuse or HACR circuit breaker.

†460v motor

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 UL, Canada units
may be fuse or circuit breaker.

2. Electrical data based on 95 F ambient outdoor-air temperature ± 10%

voltage.

3. 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 volt-
age       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.

This amount of phase imbalance is satisfactory as it is below the maximum
allowable 2%.

* — Single or three phase rooftop unit
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.
Determine the new MCA including the power exhaust using the following
formula:
MCA New = MCA unit only + MCA of Power Exhaust
For example, using a 581B060—unit with MCA = 28.9 and MOCP = 35, with
CRPWREXH030A01 power exhaust.
MCA New = 28.9 amps + 1.6 amps = 30.5 amps
If the new MCA does not exceed the published MOCP, then MOCP would
not change. The MOCP in this example is 35 amps and the MCA New is
below 35; therefore the MOCP is acceptable. If “MCA New” is larger than
the published MOCP, raise the MOCP to the next larger size. For separate
power, the MOCP for the power exhaust will be 15 amps per NEC.

76

76.0

55.9 66.0 64.0 66.2

68.4

64.5

61.7

57.3

80

80.0

59.1 68.9 68.7 71.9

74.0

68.9

65.7

59.0

024

(2 tons)

208/

230-1-60

STD

187

254

1

10.9

63

1

0.7

0.6

2.0

NO

16.3

20

15.6

69

YES

22.3

25

21.2

73

036

(3 tons)

208/

230-1-60

STD

187

254

1

16

88

1

0.7

0.6

4.9

NO

25.6

30

24.8

101

YES

31.6

35

30.4

106

208/

230-3-60

STD

187

254

1

10.3

77

1

0.7

0.6

4.9

NO

18.5

25

18.3

90

YES

24.5

30

23.8

95

HS

5.8

NO

19.4

25

19.3

120

YES

25.4

30

24.9

124

460-3-60

STD

414

508

1

5.1

39

1

0.4

0.3

2.2

NO

9.0

15

8.9

46

YES

11.7

15

11.4

48

HS

2.6

NO

9.4

15

9.3

60

YES

12.1

15

11.8

63

575-3-60

STD

518

632

1

4.2

31

1

0.4

0.3†

1.9

NO

7.6

10

7.5

36

YES

9.7

15

9.5

38

HS

2.0

NO

7.7

10

7.6

43

YES

9.8

15

9.6

44

Perfect Humidity

1

0.4† 

2.6† 

NO

7.7

10

8.0

48

YES

9.8

15

9.6

50

— Full Load Amps

HACR — Heating, Air Conditioning and Refrigeration
IFM

— Indoor (Evaporator) Fan Motor

— Locked Rotor Amps

— Minimum Circuit Amps

MOCP — Maximum Overcurrent Protection
NEC

— National Electrical Code

— Outdoor (Condenser) Fan Motor

— Rated Load Amps

— Underwriters’ Laboratories

= 100 x

max voltage deviation from average voltage

average voltage

Average Voltage =

452 + 464 + 455

3

 =

1371

3

 = 457

% Voltage Imbalance = 100 x

7

457

= 1.53%

IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact
your local electric utility company immediately.

036-072

1.6

N/A

0.64

15

036-072

N/A

0.68

N/A

15

ALL*

1.7

N/A

0.68

15

ALL

N/A

0.7

N/A

15