Johnson Controls YORK YMC2 Operation And Maintenance Manual

Table 99: Cycling shutdown messages
Message Description
MULTIUNIT CYCLING –
CONTACTS OPEN
The Multiunit Cycling contacts connected to I/O Board TB4-9, have
opened to initiate a cycling shutdown. If the chiller is running when this
occurs, the Pre-rotation Vanes are driven fully closed prior to shutting
down the chiller. The chiller will automatically restart when the contacts
close.
SYSTEM CYCLING –
CONTACTS OPEN
The System Cycling contacts connected to I/O Board TB4-13, have
opened to initiate a cycling shutdown. If the chiller is running when this
occurs, the Pre-rotation Vanes are driven fully closed prior to shutting
down the chiller. The chiller will automatically restart when the contacts
close.
UPS – LINE LOW
BATTERY VOLTAGE
This cycling fault initiates a soft shutdown if it is set while the chiller
state is Running. It is set during chiller state Running or Soft Shutdown
when all of the following are true:
• Battery Voltage Faults setting is enabled
• Warning – UPS – Line Low Battery Voltage warning has
been set for 60 continuous minutes
This fault is also set during chiller state Stopped when all of the
following are true:
• Battery Voltage Faults setting is enabled
• Control Voltage digital input is high (indicates line power is
available)
Battery Voltage < Line Low Battery Voltage Threshold
It is released when any of the following are true:
• Battery Voltage Faults is Disabled
• Battery Voltage > Line Low Battery Voltage Threshold + 0.1 V.
VSD – DC BUS PRE-
REGULATION
The DC Bus voltage has not increased to a value of +/- 50 volts of the
DC Bus voltage setpoint of 785 VDC within 2 seconds after entering the
pre-regulation state. 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.
VSD – HIGH DC BUS
VOLTAGE
If the DC Bus voltage exceeds the value for the given model of drive,
then this shutdown will occur.
Drive model High DC bus voltage shutdown value
0490, 0490A 878 VDC
0612A, 0730A, 0774, 1278A 985 VDC
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
107
YMC
2
Mod B with OptiView Control Center

Johnson Controls YORK YMC2 Specifications

General

Brand	Johnson Controls
Model	YORK YMC2
Category	Chiller
Language	English