Bryant Legacy 547K 14, Руководство по установке

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Field power wires are connected to the unit at line-side
pressure lugs at the main terminal block (TB1) or at factory-
installed option non-fused disconnect switch. See Fig. 21. Max
wire size is no. 2 AWG (copper only). See Fig. 22.
Fig. 21 — Disconnect Switch and Unit
Fig. 22 — Power Wiring Connections
TEST LEADS - Unit may be equipped with short leads (pig -
tails) on the field line connection points off the optional dis -
connect 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 direct -
ly to line connection pressure lugs only.
FIELD WIRING
All field wiring must comply with the NEC and local
requirements.
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
connected to a 208-v power supply, the control transformer
must be rewired by moving the black wire with the 1/4 in. fe -
male 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
transformer. Refer to unit label diagram for additional informa -
tion.
Size wire based on MCA (Minimum Circuit Amps) on the unit
informative plate. See Fig. 22 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 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
Overcurrent 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 following formula to de -
termine 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
maximum allowable 2%.
UNITS WITH FACTORY-INSTALLED NON-FUSED
DISCONNECT
The factory-installed optional non-fused disconnect (NFD)
switch is located in a weatherproof enclosure located under the
main control box. The manual switch handle and shaft are
shipped in the disconnect enclosure. Assemble the shaft and
handle to the switch at this point. Discard the factory test leads
(see Fig. 23).
Connect field power supply conductors to LINE side terminals
when the switch enclosure cover is removed to attach the
handle.
WARNING
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
Do not connect aluminum wire between disconnect switch
and unit. Use only copper wire.
Copper
Wire Only
Electric
Disconnect
Switch
Aluminum
Wire
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
% 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.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage.
Operation on improper line voltage or excessive phase im -
balance constitutes abuse and may cause damage to electri -
cal components. Such operation would invalidate any ap -
plicable Bryant warranty.
MOTOR