York VSD 292, Руководство по эксплуатации

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JOHNSON CONTROLS
35
FORM 160.00-O4
ISSUE DATE: 07/31/2019
4
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.
• 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will automatically restart if the shutdown is no longer
active. Leave the Compressor Switch in the Run posi-
tion. The chiller will start if no faults are active.
TABLE 4 -
CYCLING SHUTDOWN MESSAGE
MESSAGE DESCRIPTION
VSD - DC Bus Voltage
Imbalance
BUS VOLTAGE IMBALANCE FAULT
The DC link is filtered by many large capacitors, which are rated for 450 VDC. These
capacitors are connected in series to achieve a 900 VDC capability for the DC link.
It is important that the voltage is shared equally between the 2 sets of series capaci-
tors. Each set of capacitors must share approximately 1/2 of the total DC link voltage.
If the difference in the voltage between the 2 sets of capacitors is greater than ± 88
VDC then this shutdown will occur.
VSD - High DC Bus Voltage
BUS OVER-VOLTAGE FAULT
The DC bus voltage is continuously monitored and a shutdown will occur if the DC
bus voltage exceeds 745 VDC (for 400 VAC & 460 VAC units) or 909 VDC (for 575
VAC units). This shutdown will protect the capacitors from a voltage that exceeds
their rating.
VSD - High Internal Ambient
Temperature
HIGH AMBIENT TEMPERATURE FLT
The ambient temperature of the OSCD is monitored by a temperature sensor
mounted on the OSCD logic board. The high ambient trip threshold is 145°F (63°C)
for all models. If this fault occurs, the fans and coolant pump will remain on until the
internal ambient temperature has fallen to 137°F (58°C).
SECTION 4 - CYCLING SHUTDOWNS