York Millennium YCAS 310, Установка, эксплуатация и обслуживание

Страница: 96 / 124

YORK INTERNATIONAL
96
6.3 CHILLED LIQUID TEMP/RANGE KEY
The Chilled Liquid Temperature / Range key is used to
program the required leaving liquid control tempera-
tures for the application. When pressed, one of the fol-
lowing messages will be displayed for 3 seconds:
This message will indicate if the chiller is selected to
be controlled by Local (Control Panel) Setpoint control
or Remote (ISN, Remote PWM Signal, or Remote Con-
trol Center) Setpoint. This is controlled by the S1 Dip
Switch settings on the Microprocessor Board (see Sec-
tion 3.7).
The display will then scroll to one of the following mes-
sages depending on the type of chiller:
YCAS Models:
The display scrolls to a message showing the currently
programmed Control Range (CR) and desired Target
temperature with the cursor below the first digit of the
Control Range Low Limit Water Temperature as shown:
Key in the Low Limit of the Control Range within the
allowed limits. The micro will accept values from 10.0 -
70.0°F. For values below 38°F, Dip Switch S1, Switch
#1 on the Microprocessor Board must be properly pro-
grammed for Brine Cooling (see Section 3.7). If unac-
ceptable values are entered, or the switch is incorrectly
selected when setpoints below 38°F are entered, the
following message will be displayed before returning
to the Control Range message:
After the Low Limit Water Temperature is keyed in, the
cursor will automatically advance to the first digit of the
High Limit Water Temperature value of the Control
Range (CR) as shown:
This value should be programmed for the highest leav-
ing water temperature which is acceptable in the sys-
tem application. A typical value would be 4°F above
the Low Limit Water Temperature and is the default
value programmed into the micro. The micro will ac-
cept a value 1 - 5°F above the Low Limit Water Tem-
perature. Key in the upper limit High Limit Water Tem-
perature of the CR and press the Enter key.
The display automatically shows the Target tempera-
ture which is the midpoint of the programmed Control
Range. The Target temperature is the value which the
micro will attempt to control leaving liquid temperature.
NOTE: Failure to press the Enter key will cause the
newly programmed values to be ignored and
not entered into memory.
NOTE: A Control Range (CR) selection that is too small
for the application will result in excessive com-
pressor cycling or hunting of the compressor
slide valves. If this situation occurs, leaving
chilled liquid temperature may vary consider-
ably. It is recommended that a CR of less than
3.0°F be avoided. Increase the CR as needed
to reduce cycling and hunting.
After pressing the Enter key, the display will continue
to show the message until another key is pressed.
YDAS Models:
Programming for YDAS models is similar to that for
YCAS models given above except that the display first
scrolls to a message showing the currently programmed
Mixed Chilled Liquid Control Range (CR) and desired
Mixed Target temperature as shown:
After programming (see YCAS chiller instructions) and
pressing the Enter key the display will then scroll to a
second message showing the currently programmed
individual panel Control Range and the desired Panel
Target temperature as shown:
MIXED TEMP INDIVIDUAL PANEL RESULTING
CONTROL ALGORITHM SIGNAL ACTION
LOAD LOAD LOAD
LOAD BALANCE BALANCE
LOAD UNLOAD UNLOAD
BALANCE LOAD BALANCE
BALANCE BALANCE BALANCE
BALANCE UNLOAD UNLOAD
UNLOAD LOAD UNLOAD
UNLOAD BALANCE UNLOAD
UNLOAD UNLOAD UNLOAD
L O C A L
W A T E R T E M P C O N T R O L
R E M O T E
W A T E R T E M P C O N T R O L
C R = 4 2 . 0 T O 4 6 . 0 ° F
T A R G E T = 4 4 . 0 ° F
O U T O F R A N G E
T R Y A G A I N !
C R = 4 2 . 0 T O 4 6 . 0 ° F
T A R G E T = 4 4 . 0 ° F
C R = 4 4 . 0 T O 4 8 . 0 ° F
M I X E D T A R G E T = 4 6 . 0 ° F
C R = 4 2 . 0 T O 4 6 . 0 ° F
M I X E D T A R G E T = 4 4 . 0 ° F