Carrier WeatherExpert 50LC14, Installation Instructions Manual, Page: 38 / 84

38
Voltage to compressor terminals during operation must be within
voltage range indicated on unit nameplate. On 3-phase units, volt -
ages between phases must be balanced within 2% and the current
within 10%. Use the formula shown in the example below to de -
termine the percent of voltage imbalance. Operation on improper
line voltage or excessive phase imbalance constitutes abuse and
may cause damage to electrical components. Such operation
would invalidate any applicable Carrier warranty.
Example: Supply voltage is 230-3-60
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%.
Fig. 51 — Power Wiring Connections
CONVENIENCE OUTLETS
% 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 imbal -
ance constitutes abuse and may cause damage to electrical
components. Such operation would invalidate any applicable
Carrier warranty.
A B C
MOTOR
WARNING
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. Lock-out and tag-out this switch, if
necessary.
11 13
L1 L2 L3 Ground
(GR)
TB1
208/230-3-60
460-3-60
575-3-60
T1 T2 T3
L1 L2 L3
L1 L2 L3
Factory
Wiring
Disconnect
per NEC
Optional
Disconnect
Switch
or HACR
12
Equip
GR Lug
Ground
(GR)
Equip
GR Lug
Units Without Disconnect or HACR Option
Units With Disconnect or HACR Option