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heating air delivery temperature and provides approxi-
mately 350 CFM per ton cooling airflow for good
humidity removal.
(3.) HP-EFF (Factory Selected for 50XZ)— Heat Pump
Efficiency provides same airflow for heating and
cooling modes to increase overall HP efficiency;
approximately 350 CFM per ton.
d. AC/HP CFM ADJUST—SELECT NOMINAL, LOW, OR
HIGH AIRFLOW
The AC/HP CFM Adjust select is factory set to the
High-Hi (NOM for 060) tap. The CFM Adjust selections
NOM/LO will regulate airflow supplied for all operational
modes, except non-heat pump heating modes. HI provides
15 percent airflow over nominal unit size selected and LO
provides 10 percent airflow below nominal unit size
selected. CFM Adjust selection options are provided to
adjust airflow supplied to meet individual installation
needs for such things as noise, comfort, and humidity
removal (See Fig. 20, D as indicated).
e. ON/OFF DELAY—SELECT DESIRED
TIME DELAY PROFILE
Four motor operation delay profiles are provided to cus-
tomize and enhance system operation (See Fig. 20, E as
indicated).
Selection options are:
(1.) The standard 90 sec off delay (Factory Setting) at 100
percent airflow in cooling or heat pump heating mode.
(2.) A 30 sec cooling delay with no airflow, 90 sec off
delay at 100 percent airflow profile is used when it is
desirable to allow system coils time to heat-up/cool-
down in conjunction with the airflow in cooling or
heat pump heating mode.
(3.) A no delay option used for servicing unit or when a
thermostat is utilized to perform delay functions.
(4.) ENH, enhanced selection, provides a 30 sec cooling on
delay with no airflow, plus 150 sec at 70 percent
airflow and no off delay for added comfort.
This will minimize cold blow in heat pump operation
and could enhance system efficiency.
f. CONTINUOUS FAN—SELECT DESIRED FAN SPEED
WHEN THERMOSTAT IS SET ON CONTINUOUS FAN
(1.) LO speed—Factory setting, 50 percent cooling mode
airflow.
(2.) MED speed—Move connector to MED, 65 percent
cooling mode airflow.
(3.) HI speed—Move connector to HI, 100 percent cooling
mode airflow (See Fig. 20, F as indicated).
g. LOW-VOLTAGE CIRCUIT FUSING AND REFER-
ENCE
The low-voltage circuit is fused by a board-mounted
5–amp automotive fuse placed in series with the trans-
former SEC2 and the R circuit. The C circuit of the
transformer is referenced to chassis ground through a
printed circuit run at SEC1 connected to metal standoff
marked with ground symbol.
h. BASIC UNIT CONFIGURATION
The following basic configuration of the indoor motor will
provide ARI rated performance of the System. This BASIC
CONFIGURATION should be used when the rated ARI
performance is required, or if system enhancements such
as super dehumidify are not needed.
(1.) AUX HEAT kW/CFM-Select the heater range for the
size of electric heater installed (skip this step if no
heater is installed).
(2.) AC/HP SIZE-Factory selected to match system size
installed, please verify.
(3.) SYSTEM TYPE-Factory selected HP-EFF (for unit
50XZ).
Fig. 13—Electrical Data Legend
C03014
228
= 1 v
229
= 2 v
227
= 2 v
LEGEND
FLA
— Full Load Amps
LRA
— Locked Rotor Amps
MCA --
Minimum Circuit Amps
MOCP
—
Maximum Overcurrent Protection
RLA
— Rated Load Amps
NO TES:
1. In compliance with NEC (National Electrical Code) requirements
for multimotor and combination load equipment (refer to NE C
Articles 430 and 440), the overcurrent protective device for the
unit shall be Power
Supply fuse. The CGA (Canadian Gas
Association) units may be
fuse or circuit break
er.
2. Minimum wire size is based on 60 C copper wire. I f other than
60 C wire
is used, or if length exceeds wire length in table,
determine siz e from NEC.
.
3. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply volt-
age is greater than 2%. Use the following formula to determine
the percentage of voltage imbalance.
% Voltage imbalance
max voltage deviation from average voltage
= 100 x
average voltage
EXAMPLE: Supply voltage is 230-3-60.
AB = 228 v
BC = 231 v
AC = 227 v
228 + 231 + 227
Average Voltage =
3
686
=
3
= 229
Determine maximum deviation from average voltage.
(AB) 229 -
(BC) 231 -
(AC) 229 -
Maximum deviation is 2 v.
Determine percent of voltage imbalance.
2
% Voltage Imbalance = 100 x
229
= 0.8%
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.
®
*
Heater capacity (kW) based on heater voltage of 208v & 240v.
If power distibution voltage to unit varies from rated heater
voltage, heater kW will vary accordingly.
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