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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
*
Heater capacity (kW) is based on heater voltage of 208 v, 240 v, or 480 v. If power distribution
voltage to unit varies from rated heater voltage, heater kW will vary accordingly.
†
Fuse or HACR circuit breaker.
NOTES:
1. In compliance with NEC requirements for multimotor and combination load equip-
ment (refer to NEC Articles 430 and 440), the overcurrent 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 percentage of voltage imbalance.
% Voltage Imbalance
= 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 460-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
Determine maximum deviation from average voltage.
(AB) 227 – 223 = 3 v
(BC) 231 – 227 = 4 v
(AC) 227 – 226 = 1 v
Maximum deviation is 4 v.
Determine percent of voltage imbalance.
% Voltage Imbalance
= 100 x
= 1.76%
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.
12
224 + 231 + 226
3
681
=
3
=
227
4
227
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