10
installation
• Motor rotation must be the same in both VFD mode and By-pass
mode.
• If cable distance between the VFD and motor is greater than 100 feet
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.
• Program the VFD for variable torque output. Flux vector and constant
torque modes may damage the gearbox.
• Do not start and stop the motor using the safety switch at the motor.
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.
Improper use of a VFD may cause damage to equipment or personal
injury. Failure to correctly install the VFD drive will automatically
void all warranties associated with the motor and any equipment
that is either electrically or mechanically (directly) attached to the
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
damage to the equipment and possible injury.
Warning
Warning
