Johnson Controls YORK HYP1100A, Operation Manual, Page: 19 / 24

JOHNSON CONTROLS
19
FORM 160.00-O10
ISSUE DATE: 8/24/2020
3
SECTION 3 - CYCLING SHUTDOWNS
• If the chiller is running at the time of the shut-
down, the Control Center will start a coastdown
period (150 seconds for centrifugal chillers).
• The message “VSD Shutdown - Requesting Fault
Data”...will be displayed when the Control Center
is requesting the fault data from the OSCD.
• The OSCD or Harmonic Filter Logic Board will
send a shutdown code to the Control Center. The
Micro Board will interpret the shutdown code,
and display a shutdown message on the display of
the Control Center.
After the coastdown period has timed out, the chiller
will automatically restart if the shutdown is no longer
active.
TABLE 3 -
CYCLING SHUTDOWN MESSAGE
MESSAGE DESCRIPTION
VSD – DC BUS PRE-
REGULATION
The DC bus voltage has not increased to a value of +/- 50 volts of the DC bus voltage
setpoint within 2 seconds after entering the pre-regulation state. The setpoint value is
dependent on the rated input voltage of the VSD, and the rated motor voltage. If this
condition does not pass, then this shutdown is generated.
The VSD will attempt another pre-charge and pre-regulation cycle after a delay of 10
seconds. If this shutdown occurs three consecutive times, then the chiller will lock out on
a “VSD – DC BUS PRE-REGULATION LOCKOUT”.
RATED INPUT
VOLTAGE
RATED MOTOR
VOLTAGE
DC BUS VOLTAGE
SETPOINT
380-415 380-460 680
460 380-460 750
380-460 575 820
VSD – HIGH DC BUS
VOLTAGE
If the DC bus voltage exceeds the value for the given model of drive, then this shutdown
will occur. Typically, this shutdown will occur when there is a sudden change in the input
voltage due to storms, utility power problems, or site power problems.
DRIVE MODEL HIGH DC BUS VOLTAGE SHUTDOWN VALUE
1100/1300 985 VDC
VSD – HIGH INTERNAL
AMBIENT TEMPERATURE
The variable speed drive contains two temperature sensors, which monitor the unit’s
internal ambient temperature. This shutdown is generated when the higher of the two
ambient temperatures exceeds a high limit of 158°F (70°C). The unit’s fan(s) and water
pump(s) remain energized until the internal temperature drops below 148°F (64°C), after
which they shall be de-energized and the fault can be cleared. Some potential causes for
this shutdown are internal VSD fan failure, VSD coolant pump failure, entering condenser
water temperature higher than design, condenser water flow lower than required, fouled
VSD heat exchanger, or restriction of condenser water to the VSD.
General Information
The Shutdowns are organized in alphabetical order
based on the OptiView Control Center Panel messages.
The Microcomputer Control Panel messages are also
included under these headings.
Whenever the OSCD or Harmonic Filter Logic Board
generates a Cycling Shutdown a series of events will
occur.
• If the chiller is not running at the time of the shut-
down, the OSCD Logic Board will not turn on the
output transistors.
• The K1 relay on the OSCD logic board will de-
energize. This action will indicate to the Control
Center that the OSCD has shutdown. The K1 re-
lay will remain de-energized until the cause of the
shutdown has been corrected.