Bryant COMMERCIAL SINGLE PACKAGE ROOFTOP GAS HEAT/ELECTRIC COOLING 581B - Manual (Page 48)

48
ELECTRICAL DATA (cont)
581B090-120 HIGH-STATIC MOTOR (Units Without Electrical Convenience Outlet)
581B090-120 HIGH-STATIC MOTOR (Units With Electrical Convenience Outlet)
LEGEND
*Used to determine minimum disconnect per NEC.
†Fuse or HACR circuit breaker per NEC.
NOTES:
1. In compliance with NEC requirements for multimotor and combina-
tion load equipment (refer to NEC Articles 430 and 440), the overcur-
rent protective device for the unit shall be fuse or HACR breaker. The
UL, Canada approved 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.
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 maxi-
mum allowable 2%.
IMPORTANT: If the supply voltage phase imbalance is more than 2%,
contact your local electric utility company immediately.
UNIT
581B
NOMINAL
VOLTAGE
(V-Ph-Hz)
VOLTAGE
RANGE
COMPRESSOR
(each)
OFM IFM
COMBUSTION
FAN MOTOR
POWER
SUPPLY
MINIMUM UNIT
DISCONNECT
SIZE*
Min Max RLA LRA FLA FLA RLA MCA MOCP FLA LRA
090
208/230-3-60 187 254 12.4 88.0 1.4 10.6 0.6 41.3 45† 44 267
460-3-60 414 508 6.4 44.0 0.7 4.8 0.3 20.6 25† 22 134
575-3-60 518 632 4.8 34.0 0.7 4.8 0.3 15.8 20† 17 95
102
208/230-3-60 187 254 15.0 99.0 1.4 10.6 0.6 47.2 60† 50 264
460-3-60 414 508 8.2 49.5 0.7 4.8 0.3 24.7 30† 26 132
575-3-60 518 632 5.8 40.0 0.7 4.8 0.3 18.0 20† 19 107
120
208/230-3-60 187 254 17.3 125.0 1.4 15.0 0.6 56.7 70 61 360
460-3-60 414 508 9.0 62.0 0.7 7.4 0.3 29.1 35† 29 181
575-3-60 518 632 7.1 50.0 0.7 7.4 0.3 23.0 25† 23 136
UNIT
581B
NOMINAL
VOLTAGE
(V-Ph-Hz)
VOLTAGE
RANGE
COMPRESSOR
(each)
OFM IFM
COMBUSTION
FAN MOTOR
POWER
SUPPLY
MINIMUM UNIT
DISCONNECT
SIZE*
Min Max RLA LRA FLA FLA RLA MCA MOCP FLA LRA
090
208/230-3-60 187 254 12.4 88.0 1.4 10.6 0.6 47.3 50† 49 267
460-3-60 414 508 6.4 44.0 0.7 4.8 0.3 23.3 25† 24 134
575-3-60 518 632 4.8 34.0 0.7 4.8 0.3 18.5 20† 19 95
102
208/230-3-60 187 254 15.0 99.0 1.4 10.6 0.6 53.2 60† 55 264
460-3-60 414 508 8.2 49.5 0.7 4.8 0.3 27.4 30† 28 132
575-3-60 518 632 5.8 40.0 0.7 4.8 0.3 20.7 25† 21 107
120
208/230-3-60 187 254 17.3 125.0 1.4 15.0 0.6 62.7 70 66 360
460-3-60 414 508 9.0 62.0 0.7 7.4 0.3 31.8 35† 32 181
575-3-60 518 632 7.1 50.0 0.7 7.4 0.3 25.7 30† 25 147
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
UL — Underwriters’ Laboratories
= 100 x
max voltage deviation from average voltage
average voltage
Average Voltage =
452 + 464 + 455
3
=
1371
3
7
457