Bryant 548J*17 D Series, Installation Instructions Manual

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Voltage to compressor terminals during operation must be
within voltage range indicated on unit nameplate. On
3--phase units, voltages between phases must be balanced
within 2% and the current within 10%. Use the formula
below to determine the percent of voltage imbalance.
% Voltage
Imbalance = 100 x
max voltage deviation from average voltage
average voltage
Example: Supply voltage is 230-3-60
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
= 227
3 3
Determine maximum deviation from average voltage.
(AB) 227 – 224 = 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
4
= 1.76%
227
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.
Convenience Outlets —
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal
injury or death.
Units with convenience outlet circuits may use
multiple disconnects. Check convenience outlet for
power status before opening unit for service. Locate
its disconnect switch, if appropriate, and open it.
Tag--out this switch, if necessary.
!
WARNING
Two types of convenience outlets are offered as
factory--installed options on 548J units: Non--powered and
unit--powered. Both types provide a 125--volt GFCI
(ground--fault circuit--interrupter) duplex receptacle rated
at 15--A behind a hinged waterproof access cover, located
on the end panel of the unit. See Fig. 24.
Convenience
Outlet
Electric
Disconnect
Switch
Control Box
Access Panel
C09119
Fig. 24 -- Convenience Outlet Location
A 20 amp non--powered convenience outlet is available as
a field--installed accessory.
Non--powered type:
This type requires the field
installation of a general--purpose 125--volt 15--A circuit
powered from a source elsewhere in the building. Observe
national and local codes when selecting wire size, fuse or
breaker requirements and disconnect switch size and
location. Route 125--v power supply conductors into the
bottom of the utility box containing the duplex receptacle.
Unit--powered type: A unit--mounted transformer is
factory--installed to stepdown the main power supply
voltage to the unit to 115--v at the duplex receptacle. This
option also includes a manual switch with fuse, located in
a utility box and mounted on a bracket behind the
convenience outlet; access is through the unit’s control
box access panel. See Fig. 18.
The primary leads to the convenience outlet transformer are
not factory--connected. If local codes permit, the transformer
primary leads can be connected at the line--side terminals on
the unit--mounted non--fused disconnect switch; this will
provide service power to the unit when the unit disconnect
switch switch is open. See Fig. 25.
C09250
UNIT
VOLTAGE
CONNECT
AS
PRIMARY
CONNECTIONS
TRANSFORMER
TERMINALS
208,
230
240
L1: RED +YEL
L2: BLU + GRA
H1 + H3
H2 + H4
460 480
L1: RED
Splice BLU + YEL
L2: GRA
H1
H2 + H3
H4
575 600
L1: RED
L2: GRA
H1
H2
Fig. 25 -- Powered Convenience Outlet Wiring
Duty cycle: the unit--powered convenience outlet has a
duty cycle limitation. The transformer is intended to
provide power on an intermittent basis for service tools,
lamps, etc; it is not intended to provide 15--amps loading
for continuous duty loads (such as electric heaters for
overnight use). Observe a 50% limit on circuit loading
above 8--amps (i.e., limit loads exceeding 8--amps to 30
minutes of operation every hour).