Safety Shutdowns; General Information - York VSD 270 Operation Manual

Safety shutdowns

General information

The Shutdowns are organized in alphabetical order based on the OptiView™ Control Center
messages. The Microcomputer Control Center messages are also included under these headings.
Whenever a Safety Shutdown is generated by the OSCD or Harmonic Filter Logic Board, a series of
events occurs.
• If the chiller is not running at the time of the shutdown, the OSCD Logic Board does not turn
on the gate drivers.
• The K1 relay on the OSCD logic board de-energizes to indicate to the Control Center that the
OSCD has shut down. The K1 relay remains de-energized until the cause of the shutdown is
corrected.
• If the chiller is running at the time of the shut- down, the Control Center starts a coastdown
period (150 seconds for centrifugal chillers or shorter for those chillers that contain the
optional Quick Start feature).
• The message "VSD Shutdown - Requesting Fault Data" is displayed when the Control Center
requests the fault data from the OSCD.
• The OSCD or Harmonic Filter Logic Board sends a shutdown code through the
communications link to the Control Center. The microboard interprets the shutdown code
and displays a shutdown message on the display of the Control Center.
After the coastdown period times out, you can restart the chiller if the shutdown is no longer
active. Place the Compressor Switch in the Stop/Reset position, and then into the Start position and
release. The chiller starts if no faults are active.
34 Liquid-Cooled OptiSpeed Compressor Speed Drive