10
installation
• Motor rotationmust be the samein both VFD mode and By-pass
mode.
• IfcabledistancebetweentheVFDandmotorisgreaterthan100feet
a DV/DT output filter is recommended to avoid damage to the motor.
100 feet distance is based on our field experience, the VFD manufac-
ture may state different distances and distance does vary depending
on the VFD manufacture.
• ProgramtheVFDforvariabletorqueoutput.Fluxvectorandconstant
torque modes may damage the gearbox.
• Donotstartandstopthemotorusingthesafetyswitchatthemotor.
If the drive is being commanded to run and the load side is cycled ON
and OFF with the safety switch this may damage the VFD.
Using a VFD in cooling applications has advantages over traditional single
or two speed motor control. A VFD can reduce the cost of electrical energy
being used and provide better temperature control. In addition, it reduces the
mechanical and electrical stress on the motor and mechanical equipment.
Electrical savings can be large during periods of low ambient temperature
when the cooling requirement can be satisfied at reduced speeds. To benefit
from these advantages, it is important that the drive be installed correctly.
Marley supplies VFD and VFD controls specifically designed for our cool-
ing products. If you have purchased a Marley VFD and/or controls package,
please follow the instructions in the User Manual for that system. Most VFD
problems can be avoided by purchasing the Marley drive system. If you are
installing a VFD other than the Marley drive, please refer to that drives instal-
lation manual.
ImproperuseofaVFDmaycausedamagetoequipmentorpersonal
injury. Failure to correctly install the VFD drive will automatically
voidallwarrantiesassociatedwiththemotorandanyequipment
thatiseitherelectricallyormechanically(directly)attachedtothe
VFD drive system. The length of this warranty avoidance will be
contingent on properly installing the VFD system and repairing any
damage that may have occurred during its operation. SPX Cool-
ing Technologies does not assume responsibility for any technical
support or damages for problems associate with non-Marley brand
VFD systems.
Changing the operational fan speed from the factory settings could
cause the fan to operate in an unstable region which may result in
damagetotheequipmentandpossibleinjury.
Warning
Warning