FORM 201.10-NM4
109
YORK INTERNATIONAL
6.4 REMOTE RESET TEMP/RANGE KEY
Remote Setpoint Reset allows resetting the setpoint
upward from the programmed value in memory. This
feature is typically used for demand limiting or ice stor-
age application. Reset is accomplished by timed clo-
sure of external contacts for a defined period of time
and allows reset of the setpoint upward by up to 40°F
above the setpoint programmed in memory see Sec-
tion 1.7.
The maximum allowable reset must be programmed
into memory and can be a value of 2° to 40°F depend-
ing on user requirements. To program the reset, press
the Remote Reset Temperature Range key. The follow-
ing message will appear:
The display indicates the Remote Setpoint, which is al-
ways equal to the chilled liquid setpoint programmed
by the Chilled Liquid Temperature / Range key plus the
offset from the remote reset signal. The display will also
show the Remote Range which is the programmed
maximum reset allowed for the application. The cursor
will stop beneath the first digit of the Remote Range.
Key in the maximum reset allowed for the application,
remembering to use a leading 0 for values less than
10°F, then press the Enter key to store the new value in
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 YDAS 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:
These values can now be programmed.
The recom-
mended CR and TARGET for the individual panels
should be programmed 2.0 4.0 °F below the
fiMixedfl programmed values. Both Master
and
Subordinate
Panels will be programmed to the
PANEL TARGET
after the ENTER key is pressed.
NOTE:
Remember to program the Mixed Target tem-
perature to a slightly higher value than the Panel
Target temperature.
NOTE: Failure to press the Enter key will cause the
newly programmed values to be ignored and
not entered into memory.
R E M
S E T P O I N T
=
4 0 . 0
R E M
R A N G E
=
2 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
Содержание Millennium YDAS 410
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