York R123 - Manual (Page 59)

FORM 160.55-O1 (604)
59
YORK INTERNATIONAL
Local Leaving Chilled Liquid Tem per a ture -
Setpoint
Access Level Required: OPERATOR
This value allows the user to deÞ ne the Leav ing Chilled
Liquid Temperature that is to be maintained by the chill er.
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 re mote
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 cre at ing an off set above the operator pro grammed
BASE Leaving Chilled Liquid Tem per a ture setpoint.
This off set may be deÞ ned up to 10.0°F or 20.0°F above
the BASE setpoint (see the Remote Leav ing Chilled Liq-
uid Tem per a ture Setpoint Range de scrip tion above).
Ad di tion al ly, a MicroGateway (in ISN Remote mode)
can de Þ ne the setpoint through a serial data stream. In
this case, the incoming setpoint is not an offset that is
ap plied to the locally programmed BASE setpoint value,
but rath er is the setpoint value itself.
Leaving Chilled Liquid Temperature
Cycling Off set - Shutdown
Access Level Re quired: 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-
PER A TURE cycling shutdown. This is done by de Þ n ing
an offset below the Leaving Chilled Liquid Tem per a ture
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 es tab lish es the minimum allowed tem per a ture for the
Leaving Chilled Liquid Temperature and pre vents over-
cooling of the building. Anytime the Leaving Chilled
Liquid Temperature setpoint is in creased, 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 be comes
the programmed setpoint value.
Leaving Chilled Liquid Temperature
Cycling Off set - Restart
Access Level Re quired: OPERATOR
This value allows the user to specify the Leaving Chilled
Liquid Temperature at which the chiller will restart af ter a
shutdown on a LEAVING CHILLED LIQUID – LOW
TEMPERATURE cycling shut down. This is done by
deÞ ning an offset above the Leaving Chilled Liq uid
Temperature setpoint. It is programmable over a range
of 0°F to 70°F above the setpoint, to a max i mum restart
value of 80°F. The chiller will au to mat i cal ly re start when
this tem per a ture is reached. This setpoint can be used
to reduce chiller cycling by de lay ing the chiller restart
until the cooling load has in creased.
Remote Analog Input Range
Access Level Required: OPERATOR
This setpoint deÞ nes, for the Control Center, the re mote
signal range applied for remote reset of the Leav ing
Chilled Liquid Temperature Setpoint and Current Limit
Setpoint in ANALOG remote mode. If the re mote
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: OP ER A TOR
Allows the user to specify the maximum al lowed mo-
tor current (as a percentage of FLA). When the motor
cur rent 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: OP ER A TOR
Allows the user to specify the current limit val ue (as
a percentage of Full Load Amps) to which the chill er
will be limited during the speciÞ ed pulldown limit time.
This value will override the Motor Current Limit value
dur ing this time period. This function is used to provide
energy savings following chiller start-up.
Pulldown Demand Time
Access Level Required: OP ER A TOR
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 Re quired: VIEW
Causes an instant return to the Home Screen.
Setup
Access Level Re quired: VIEW
Moves to the subscreen allowing setup of gen er al sys tem
parameters.
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