LEESON FHP Series Chassis Mount Variable Speed Drives - Manual (Page 29)

19 Installation
If the drive continues to pick up noise after grounding the
shield, it may be necessary to add AC line filtering devices,
or to mount the drive in a less noisy environment.
Logic wires from other input devices, such as motion
controllers and PLL velocity controllers, must be separated
from power lines in the same manner as the logic I/O on
this drive.
Heat sinking
LEESON 1-HP FHP drives (175322, 175323, & 175311)
drives are delivered with a factory-installed heat sink. All
other FHP-series drives have sufficient heat sinking in their
basic configurations. No additional heat sinking is
necessary.