York YT Millennium, Эксплуатация и техническое обслуживание

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FORM 160.55-O1 (920)
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YORK INTERNATIONAL
Local Leaving Chilled Liquid Temperature -
Setpoint
Access Level Required : OPERATOR
This value allows the user to define the Leaving Chilled
Liquid Temperature that is to be maintained by the chiller.
It is programmable over the range of 38.0°F to 70.0°F
(water) or 10.0°F to 70.0°F (brine). If Smart Freeze is
enabled, the range is 36.0°F to 70.0°F (water). A remote
device can provide an analog signal (0-20mA, 4-20mA,
0-10VDC or 2-10VDC) in Analog Remote mode or PWM
signal in Digital Remote mode that changes the setpoint
by creating an offset above the operator programmed
BASE Leaving Chilled Liquid Temperature setpoint.
This offset may be defined up to 10.0°F or 20.0°F above
the BASE setpoint (see the Remote Leaving Chilled Liq-
uid Temperature Setpoint Range description above).
Additionally, a MicroGateway (in ISN Remote mode)
can define the setpoint through a serial data stream. In
this case, the incoming setpoint is not an offset that is
applied to the locally programmed BASE setpoint value,
but rather is the setpoint value itself.
Leaving Chilled Liquid Temperature
Cycling Offset - Shutdown
Access Level Required : OPERATOR
This value allows the user to specify the Leaving Chilled
Liquid Temperature at which the chiller will shut down
on a
LEAVING CHILLED LIQUID – LOW TEM-
PERATURE cycling shutdown. This is done by defining
an offset below the Leaving Chilled Liquid Temperature
setpoint. It is programmable over a range of 1°F to 64°F
below the setpoint, to a minimum cutout of 36°F (water),
34°F (water with Smart Freeze enabled) or 6°F (brine).
It establishes the minimum allowed temperature for the
Leaving Chilled Liquid Temperature and prevents over-
cooling of the building. Anytime the Leaving Chilled
Liquid Temperature setpoint is increased, the shutdown
threshold is 36.0°F (water) or 6.0°F (brine) for the next
ten (10) minutes. If Smart Freeze is enabled, the thresh-
old is 34.0°F for the next 10 minutes. After ten (10)
minutes have elapsed, the shutdown threshold becomes
the programmed setpoint value.
Leaving Chilled Liquid Temperature
Cycling Offset - Restart
Access Level Required : OPERATOR
This value allows the user to specify the Leaving Chilled
Liquid Temperature at which the chiller will restart after a
shutdown on a LEAVING CHILLED LIQUID – LOW
TEMPERATURE cycling shutdown. This is done by
defining an offset above the Leaving Chilled Liquid
Temperature setpoint. It is programmable over a range
of 0°F to 70°F above the setpoint, to a maximum restart
value of 80°F. The chiller will automatically restart when
this temperature is reached. This setpoint can be used
to reduce chiller cycling by delaying the chiller restart
until the cooling load has increased.
Remote Analog Input Range
Access Level Required : OPERATOR
This setpoint defines, for the Control Center, the remote
signal range applied for remote reset of the Leaving
Chilled Liquid Temperature Setpoint and Current Limit
Setpoint in ANALOG remote mode. If the remote
signal is 0-10VDC or 0-20mA, this setpoint must be
programmed for 0-10VDC. If the remote signal is 2-
10VDC or 4-20mA, this setpoint must be programmed
for 2-10VDC.
Local Motor Current Limit
Access Level Required : OPERATOR
Allows the user to specify the maximum allowed mo-
tor current (as a percentage of FLA). When the motor
current reaches this value, the pre-rotation vanes will
not be permitted to open further. If the motor current
rises above this value, the pre-rotation vanes will close
to reduce the current to this value.
Pulldown Demand Limit
Access Level Required : OPERATOR
Allows the user to specify the current limit value (as
a percentage of Full Load Amps) to which the chiller
will be limited during the specified pulldown limit time.
This value will override the Motor Current Limit value
during this time period. This function is used to provide
energy savings following chiller start-up.
Pulldown Demand Time
Access Level Required
: OPERATOR
Allows the user to set a period of time for which the pulldown
demand limit will be in effect after the chiller starts.
Print
Access Level Required:
VIEW
Generates Setpoints print report.
NAVIGATION
Home
Access Level Required : VIEW
Causes an instant return to the Home Screen.
Setup
Access Level Required : VIEW
Moves to the subscreen allowing setup of general system
parameters.
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