York YCAS0098EB, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
Key in the desired Chilled Liquid Setpoint and the al-
lowable deviation (Range). The micro will accept values
from 10.0 - 70.0°F (-12 to 21°C). For values below 40°F
(4°C), Dip Switch S1, Switch #1 on the Microprocessor
Board must be properly programmed for Brine Cooling
(see Section 3.7). If unacceptable values are entered,
or the switch is incorrectly selected when setpoints
below 40°F (4°C) are entered, the following message
will be displayed before returning to the Control Range
message:
After the Setpoint is keyed in, the cursor will automat-
ically advance to the first digit of the Range as shown:
This value should be programmed for the maximum al-
lowable positive and negative chilled liquid temperature
deviation that is acceptable from setpoint in the system
application. A typical value would be +/- 2.0°F (1°C).
The micro will accept a range from 1.5 - 2.5°F (- °C).
After the Setpoint and Range is keyed in, press the
ENTER Key to store the data in memory.
Failure to press the Enter key will
cause the newly programmed values
to be ignored and not entered into
memory.
After pressing the Enter key, the display will continue
to show the message until another key is pressed.
6.4 REMOTE COOLING SETPOINTS KEY
Remote Cooling Setpoints key allows resetting the set-
point upward from the programmed value in memory
from a remote device. This feature is typically used for
demand limiting or ice storage applications. Reset is
accomplished by timed closure of external contacts for
a defined period of time and allows reset of the setpoint
upward by up to 40°F (22°C) above the setpoint pro-
grammed in memory – see Section 1.7.
The maximum allowable reset must be programmed
into memory and can be a value of 2 to 40°F (1 to 22°C)
depending on user requirements. To program the reset,
press the Remote Reset Temperature Range key. The
following message will appear:
The display indicates the Remote Setpoint which is
always 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 Range which is the programmed maximum
deviation allowed for the application. This display is
not programmable, and will change the setpoint only
through a signal from a remote device.
Pressing the REM RESET TEMP RANGE Key again
scrolls the display to the MAX EMS-PWM REMOTE
TEMP RESET which is programmable. This should be
programmed to the maximum offset which is required
for the application. The maximum programmable value
is 40° F (22°C), while the minimum programmable
value is 2°F (1°C).
The cursor will stop beneath the first digit of the max -
imum reset. Key in the maximum reset allowed for the
application, remembering to use a leading “0” for values
less than 10°F (or 10°C). Press the ENTER Key to store
the new value in memory.
O U T O F R A N G E -
T R Y A G A I N !
S E T P O I N T = 4 4 . 0 ° F
R A N G E = + / - 2 . 0 ° F
R E M S E T P = 4 4 . 0 ° F
R A N G E = + / - 2 . 0 ° F
M A X E M S - P W M R E M O T E
T E M P R E S E T = + 4 0 ° F
6.3 LOCAL COOLING SETPOINTS KEY
The Local Cooling Setpoints key is used to program the
required Leaving Chilled Liquid control temperatures
for the application. When the key is pressed, the fol-
lowing message will be displayed:
S E T P O I N T = 4 4 . 0 ° F
R A N G E = + / - 2 . 0 ° F
Micro Panel Contents