Bryant 551A, User Manual

Page: 148 / 170

148
ELECTRICAL DATA (cont)
ELECTRICAL DATA — 558F180-300 (cont)
LEGEND AND NOTES FOR ELECTRICAL DATA TABLES
LEGEND
*Heater capacity (kW) is based on heater voltage of 208 v, 240 v, 480 v, and
600 v. Heaters are rated at 240 v, 480 v, or 600 v. If power distribution voltage to
unit varies from rated heater voltage, heater kW will vary accordingly. To deter-
mine heater capacity at actual unit voltage, multiply 240 v, 480 v, or 600 v capac-
ity by multipliers found in table on page 130. Electric heaters are field installed.
†Fuse or HACR circuit breaker.
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 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 percent of voltage
imbalance.
% Voltage Imbalance
EXAMPLE: Supply voltage is 460-3-60.
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 voltage imbalance.
= 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.
3. MCA calculation for 558F180-300 units with electric heaters over 50 kW =
(1.25 x IFM amps) + (1.00 x heater FLA).
UNIT
558F
NOMINAL
VOLTAGE
(3 Ph, 60 Hz)
VOLTAGE
RANGE
COMPRESSOR
OFM IFM
POWER
EXHAUST
ELECTRIC
HEAT*
POWER SUPPLY
NO. 1 NO.2
Min Max RLA LRA RLA LRA Qty Hp
FLA
(ea)
Hp FLA FLA LRA kW FLA MCA MOCP†
240
208/230 187 253 42 239 33.6 225 2 1 6.6 7.5 25.0/25.0
— — — — 124/124 150/150
4.6 18.8 — — 129/129 150/150
— — 26/34 71/ 82 124/134 150/150
4.6 18.8 26/34 71/ 82 129/140 150/150
— — 42/56 117/135 178/166 200/175
4.6 18.8 42/56 117/135 183/172 200/175
— — 56/75 156/180 187/211 200/225
4.6 18.8 56/75 156/180 193/217 200/225
460 414 508 19.2 125 17.3 114 2 1 3.3 7.5 13.0
— — — — 61 80
2.3 6 — — 63 80
— — 32 39 65 80
2.3 6 32 39 68 80
— — 55 66 82 90
2.3 6 55 66 85 90
— — 80 96 112 125
2.3 6 80 96 115 125
300
208/230 187 253 41.4 312 47.1 245 6 0.5 1.7 10.0 28.0/28.0
— — — — 138/138 175/175
4.6 18.8 — — 143/143 175/175
— — 26/34 71/ 82 138/138 175/175
4.6 18.8 26/34 71/ 82 143/143 175/175
— — 42/56 117/135 181/170 200/175
4.6 18.8 42/56 117/135 187/176 200/200
— — 56/75 156/180 191/215 200/225
4.6 18.8 56/75 156/180 197/221 200/225
460 414 508 20 150 19.6 125 6 0.5 0.8 10.0 14.6
— — — — 64 80
2.3 6 — — 66 80
— — 32 39 67 80
2.3 6 32 39 70 80
— — 55 66 84 90
2.3 6 55 66 87 100
— — 80 96 114 125
2.3 6 80 96 117 125
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
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage =
452 + 464 + 455
3
=
1371
3
= 457
% Voltage Imbalance = 100 x
7
457
0
T
F
Q
0
04
-0
12
55
8F1
80-
30
0