User Guide

244
ELECTRICAL DATA — 581A (cont)
ELECTRICAL DATA — 581A155,180
LEGEND
*Fuse or HACR circuit breaker.
NOTES:
1. In compliance with NEC requirements for multimotor and combina-
tion load equipment (refer to NEC Articles 430 and 440), the over-
current protective device for the unit shall be fuse or HACR
breaker. 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 per-
cent 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%, contact your local electric utility company immediately.
UNIT
581A
NOMINAL
VOLTAGE
(3 Ph, 60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM IFM
POWER
EXHAUST
COMBUSTION
FAN MOTOR
POWER
SUPPLY
No. 1 No. 2
Min Max RLA LRA RLA LRA Qty Hp FLA (ea) Hp FLA FLA LRA FLA MCA MOCP*
155
(Standard
IFM)
208/230 187 253 20.7 156 20.7 156 3 0.5 1.70 2.9 8.8/ 8.4
— — 0.57 60/60 80/80
4.6 18.8 0.57 65/65 80/80
460 414 506 10.0 75 10.0 75 3 0.5 0.80 2.9 4.2
— — 0.30 29 35
2.3 6.0 0.30 31 40
575 518 633 8.2 54 8.2 54 3 0.5 0.75 3.0 3.9
— — 0.57 25 30
2.1 4.8 0.57 27 30
155
(Optional
IFM)
208/230 187 253 20.7 156 20.7 156 3 0.5 1.70 3.7 10.5/11.0
— — 0.57 62/63 80/80
4.6 18.8 0.57 67/67 80/80
460 414 506 10.0 75 10.0 75 3 0.5 0.80 3.7 4.8
— — 0.30 30 35
2.3 6.0 0.30 32 40
180
208/230 187 253 32.1 195 20.7 156 3 0.5 1.70 5.0 15.8/15.8
— — 0.57 82/82 110/110
4.6 18.8 0.57 86/86 110/110
460 414 506 16.4 95 10.0 75 3 0.5 0.80 5.0 7.9
— — 0.30 41 50
2.3 6.0 0.30 43 50
575 518 633 12.0 80 8.2 54 3 0.5 0.75 5.0 6.0
— — 0.57 31 40
2.1 4.8 0.57 34 45
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
Average Voltage =
452 + 464 + 455
3
=
1371
3
7
457
581A155-300