![](/images/new-backgrounds/1044749/4474915x1.webp)
Fig. 10 Ð Condensate Drain Piping Details
VI. STEP 5 Ð MAKE ELECTRICAL CONNECTIONS
A. Field Power Supply
Unit is factory wired for voltage shown on nameplate.
When installing units, provide a disconnect, per NEC (Na- tional Electrical Code) requirements, of adequate size (Table 2).
All ®eld wiring must comply with NEC and local requirements.
Route power lines through control box access panel or unit basepan (Fig. 4 and 5) to connections as shown on unit wir- ing diagram and Fig. 11.
Operating voltage to compressor must be within voltage range indicated on unit nameplate. On
CAUTION: The correct power phasing is critical in the operation of the scroll compressors. An incorrect phas- ing will cause the compressor to rotate in the wrong di- rection. This may lead to premature compressor failure.
Use the following formula to determine the percentage of volt- age imbalance.
Percentage of Voltage Imbalance
= 100 x | max voltage deviation from average voltage | |
average voltage | ||
|
EXAMPLE: Supply voltage is
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage = | 452 + 464 + 455 | |
3 | ||
| ||
= | 1371 | |
| 3 | |
= | 457 |
Determine maximum deviation from average voltage:
(AB) 457 − 452 = 5 v
(BC) 464 − 457 = 7 v
(AC) 457 − 455 = 2 v
Maximum deviation is 7 v.
Determine the percentage of voltage imbalance:
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.
Unit failure as a result of operation on improper line voltage or excessive phase imbalance constitutes abuse and may cause damage to electrical components.
B. Field Control Wiring
Install a
Route thermostat cable or equivalent single leads of no. 18 AWG (American Wire Gage) colored wire from subbase terminals through conduit in unit to
NOTE: For wire runs up to 50 ft, use no. 18 AWG insulated wire (35 C minimum). For 50 to 75 ft, use no. 16 AWG insu- lated wire (35 C minimum). For over 75 ft, use no. 14 AWG insulated wire (35 C minimum). All wire larger than no. 18 AWG cannot be directly connected to the thermostat and will require a junction box and splice at the thermostat.
Set heat anticipator settings as indicated in Table 3. Settings may be changed slightly to provide a greater degree of com- fort for a particular installation.
Refer to accessory remote control instructions as required.
TB1 MAXIMUM WIRE SIZE
| UNIT |
| VOLTAGE | ||
| 559F |
| 208/230 |
| 460 |
| All |
| 350 kcmil |
| 2/0 |
|
|
| LEGEND |
|
|
EQUIP Ð Equipment | NEC Ð National Electrical | ||||
GND | Ð Ground |
|
| Code | |
kcmil | Ð Thousand Circular TB | Ð Terminal Block | |||
| Mils |
|
|
|
Fig. 11 Ð Field Power Wiring Connections
Percentage of Voltage Imbalance = 100 x
7
457
= 1.53%
UNIT
Fig. 12 Ð Field Control Thermostat Wiring
Ð8Ð