Bryant 542J, 549B Legend And Notes For Electrical Tables, ELECTRICAL DATA cont, 548F036-120

Models: 549B 548F 542J

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LEGEND AND NOTES FOR ELECTRICAL TABLES

ELECTRICAL DATA (cont)

LEGEND AND NOTES FOR ELECTRICAL TABLES

548F036-120

LEGEND

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

*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, 480 v, and 575 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 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.

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

= 100 x

max voltage deviation from average voltage

average voltage

 

Example: Supply voltage is 460-3-60.

AB = 452 v BC = 464 v AC = 455 v

Average Voltage = 452 + 464 + 455 3

=1371

3

=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.

7

% Voltage Imbalance = 100 x 457

= 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.

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Bryant Legend And Notes For Electrical Tables, ELECTRICAL DATA cont, 548F036-120, Unbalanced 3-PhaseSupply Voltage