Technical Specifications

Heat Rejection
117
6.12.1 Line Voltage Wiring
Drycooler rated voltage should be verified with available power supply upon receipt of unit but before
installation. Refer to the unit electrical schematic and serial tag for specific electrical requirements.
All wiring must be done in accordance with all applicable local, state and national electrical codes.
Line voltage electrical service is required for all drycoolers at the location of the drycooler. If the
drycooler contains pump controls, the pump package voltage must match the drycooler voltage. See
the unit's serial tag for specific electrical requirements of the drycooler and any pump package. A unit
disconnect is standard on drycoolers with internal pump controls and optional on all other drycoolers.
Site disconnect(s) may also be required per local code to isolate the drycooler/pumps for maintenance.
Route the supply power to the site disconnect switch and then to the drycooler. Route the conduit
through the hole provided in the cabinet. Connect earth ground to lug provided near terminal board.
6.12.2 Low Voltage Control Wiring
NOTICE
Risk of control malfunction. Can cause improper unit operation.
Make sure that all low voltage electrical wiring has been performed per the schematic
diagram provided and that all low voltage wiring connections are tight.
A control interlock between the drycooler and the indoor cooling units is required. Field-supplied cop-
per wire is required for connection between like-numbered Terminals 70 & 71 on both units for
remote On/Off control of the drycooler, synchronized with the indoor unit. Wiring must be sized and
selected for insulation class per NEC and other local codes. The recommended control circuit wire
(24VAC) size is 16AWG for lengths up to 150ft. (45m). Contact the factory for assistance with longer
wiring runs.
!
WARNING
Risk of electrical fire and short circuit. Can cause property damage, injury or death.
Select and install the electrical supply wire and overcurrent protection device(s) according to
the specifications on the unit nameplate(s), per the instructions in this manual and according
to the applicable national, state and local code requirements. Use copper conductors only.
Make sure all electrical connections are tight. Unit-specific wiring diagrams are provided on
each unit.
Table 47 60Hz electrical values - Eight-fan drycoolers without pump controls, standard models
Model # Voltage Phase FLA WSA OPD
880, 940
208/230 3 28.0 28.9 35
460 3 13.6 14.0 20
575 3 11.2 11.6 15
Values are calculated per UL 1995. OPD values may be adjusted higher than calculations to
compensate for maximum anticipated application temperatures.
Table 48 60Hz pump FLA values
Pump
hp
Input Power, Volts
208 460
10 30.8 14.0
Values based on NEC handbook values for 3-phase motors.