Bryant Legacy 549J 12 Series, Руководство по установке

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Fig. 25 — Mounting Position for Field Disconnects
(up to 100A)
All units except 208/230-v units are factory wired for the volt -
age shown on the nameplate. If the 208/230-v unit is to be con -
nected to a 208-v power supply, the control transformer must
be rewired by moving the black wire with the
1
/
4
-in. female
spade connector from the 230-v connection and moving it to
the 200-v
1
/
4
-in. male terminal on the primary side of the trans -
former. Refer to unit label diagram for additional information.
Field power wires are connected to the unit at line-side pres -
sure lugs at the main terminal block (TB1) or at factory-in -
stalled option non-fused disconnect switch. Max wire size is #2
AWG (copper only). See Fig. 26.
Fig. 26 — Power Wiring Connections
TEST LEADS — Unit may be equipped with short test leads (pig -
tails) on the field line connection points on contactor C or optional
disconnect switch. These leads are for factory-run test purposes
only; remove and discard before connecting field power wires to
unit connection points. Make field power connections directly to
line connection pressure lugs only. See Fig. 27.
Fig. 27 — Disconnect Switch and Unit
ALL UNITS
All field wiring must comply with NEC and all local codes.
Size wire based on MCA (Minimum Circuit Amps) on the unit
informative plate. See Fig. 26 and the unit label diagram for
power wiring connections to the unit power terminal blocks
and equipment ground. Maximum wire size is #2/0 AWG
(copper only) per pole.
Provide a ground fault and short circuit over-current protection
device (fuse or breaker) per NEC Article 440 (or local codes).
Refer to unit informative data plate for MOCP (Maximum
Over-Current Protection) device size.
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 shown in the fol -
lowing example to determine the percent of voltage imbalance.
Example: Supply voltage is 230-3-60
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.
This amount of phase imbalance is satisfactory as it is below the maxi-
mum allowable 2%.
Units Without Disconnect Option
Units With Disconnect Option
2
4
6
1
3
5
L1
L2
L3
Optional
Disconnect
Switch
Disconnect factory test leads; discard.
Factory
Wiring
11 12 13
L1 L2 L3
TB1
208/230-3-60
460-3-60
575-3-60
Disconnect
per
NEC
WARNING
FIRE HAZARD
Failure to follow this warning could result in personal inju -
ry, death, or property damage.
Do not connect aluminum wire between disconnect switch
and unit. Use only copper wire.
% Voltage
Imbalance
= 100 x
max voltage deviation from average voltage
average voltage
AB = 224 v
BC = 231 v
AC = 226 v
Average Voltage =
(224 + 231 + 226)
=
681
= 227
3 3
% Voltage Imbalance = 100x
4
= 1.78%
227
IMPORTANT: If the supply voltage phase imbalance is more than 2%,
contact your local electric utility company immediately.
COPPER
WIRE ONLY
ELECTRIC
DISCONNECT
SWITCH
ALUMINUM
WIRE
A B C
MOTOR