SPX Marley NC8409 - Motor Wiring

9
installation
Motor Wiring
Wire motor leads as shown on the motor nameplate matching the supply
voltage. Do not deviate from the motor nameplate wiring.
Either of following symbols may be shown on the motor nameplate –
Δ, Δ Δ,
Y, or YY. These symbols represent how the motor is constructed on the inside
and in no way have anything to do with a Delta or Wye electrical distribution
system serving the motor.
When using a starter:
• Setmotoroverloadprotectionto110%ofmotornameplateamps.
This setting allows the fan motor to operate during cooler weather.
Duringcoolerweatheritiscommonforthemotortodraw6to10%
higher than nameplate amps. High amps are common during tower
commissioning when the tower is dry and the ambient air temperature
is cool.
Do not start the motor more than four to five times per hour. Short
cyclingthetowerwillcausefuses,breakersorO.L.stooperateand
will decrease motor life.
When using a two-speed starter:
• Motorrotationmustbethesameatslowspeedandhighspeed.
• Singlewindingmotorrequiresastarterwithashortingcontactor.
• Two-windingmotorrequiresastarterwithoutashortingcontactor.
• Alltwo-speedstartersmusthavea20secondtimedelayrelaywhen
switching from high speed to low speed.
Donotstartthemotormorethanfourtovetimesperhour(each
lowspeedstartandeachhighspeedstartcountasonestart).
When using a VFD:
Before beginning, ensure that the motor is rated for “Inverter Duty”
per NEMA MG-1, part 31.
• SettheVFDsolidstateoverloadprotectionto119%ofmotorname-
plate amps and set “maximum current parameter” in the VFD to motor
nameplate amps. “Maximum current parameter” will reduce fan speed
and limit amp draw to nameplate amps during cold weather opera-
tion.IffurnishedwithamechanicalO.L.setthisat110%overmotor
nameplate amps.
Note
Note
Note
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