Bryant AIR CONDITIONERS 564A User Manual

Page 12

C99051

452 = 5 v

457 = 7 v
455 = 2 v

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

(fuses or HACR-type circuit breaker)

NEC

— National Electrical Code

OFM

— Outdoor-Fan Motor

RLA

— Rated Load Amps

— Underwriters Laboratories

* Single-Point Wiring Connections.
† Dual-Point Wiring Connections.

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.
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

max voltage deviation from average voltage

= 100 x

average voltage

EXAMPLE: Supply voltage is 460-3-60.

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

452 + 464 + 455

Average Voltage =

1371

= 457

Determine maximum deviation from average voltage.

(AB) 457 -
(BC) 464 -
(AC) 457 -

Maximum deviation is 7 v.

Determine percent of voltage imbalance.

% 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.

Fig. 15—Cooling Charging Chart, 564A024 Units

C00015

OUTDOOR TEMP

115

105

Fig. 16—Cooling Charging Chart, 564A030 Units

C00016

OUTDOOR TEMP

115

105

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