York MILLENNIUM YB Series, Эксплуатация и техническое обслуживание

Страница: 24 / 72

24
YORK INTERNATIONAL
SERVICE INTERVAL – This key shows engine setpoint
and compressor setpoint hours. Along with the hours re-
maining before the engine/compressor is due for serv-
ice. (See page 30).
DAILY SCHEDULE – This key displays the programmed
daily start and stop times, from Sunday through Satur-
day plus Holiday. If desired, the Control Center can be
programmed to automatically start and stop the chiller
as desired. This schedule will repeat on a 7-day calendar
basis. If the Daily Schedule is not programmed, the de-
fault value is 00:00 AM start and stop times for all days of
the week and the holiday. (Note that the system will not
automatically start and stop on a daily basis with these
default values because 00:00 is an “Impossible” time for
the Micro Board. See “Programming System Setpoints”,
page 27). Finally, one or more days in the week can be
designated as a holiday (See description under “ HOLI-
DAY ” setpoint) and the Control Center can be programmed
(using “ DAILY SCHEDULE ” setpoint) to automatically start
and stop the chiller on those days so designated. The
operator can override the time clock at any time using
the “ COMPRESSOR ” switch.
NOTE: If only a start time is entered for a particular
day, the compressor will not automatically stop
until a scheduled stop time is encountered
on a subsequent day.
HOLIDAY – This key indicates which days in the upcom-
ing week are holidays. On those designated days, the
chiller will automatically start and stop via the holiday
start and stop times programmed in the “ DAILY SCHED-
ULE ” setpoint. It will do this one time only and the follow-
ing week will revert to the normal daily schedule for that
day.
REMOTE/RESET TEMP RANGE – This key displays the
maximum offset of remote LCWT setpoint reset. This off-
set is either 10° or 20°F as programmed. When in the
remote mode, this value is added to the operator pro-
grammed chilled liquid temp setpoint and the sum equals
the temperature range in which the LCWT can be reset.
For example, if the operator programmed REMOTE/RE-
SET TEMP RANGE is programmed with a value of 10°F,
then the chilled liquid temp setpoint can be remotely re-
set over a range of 46°F to 56°F (46 + 10 = 56). If not
programmed, the default value for this parameter is 20°F.
For additional information on remote LCWT reset, refer to
Form 160.60-PW3 or 160.66-PW3.
NOTE: If an Energy Management System is inter-
faced to the Control Center for the purpose
of remote LCWT setpoint reset, then the op-
erator programmed REMOTE RESET TEMP
RANGE value determines the maximum value
of temperature reset controlled by the En-
ergy Management System.
DATA LOGGER – This key is used when an optional
printer is connected to the MicroComputer Control Cen-
ter. Refer to Form 160.60-N2 for operation instructions.
DISPLAYING SYSTEM SETPOINTS
The currently programmed Setpoint values can be viewed
at any time (See page 37) in “ SERVICE ”, “ LOCAL ”
or “ REMOTE ” operating mode as follows:
• Press and release the appropriate “ SETPOINT ” key –
the message will be displayed for 2 seconds.
- or -
• Press and hold the appropriate “ SETPOINT ” key –
the message will be displayed as long as the key is
pressed.
- or -
• Press and release the appropriate “ SETPOINT ” key,
then press and release the “ DISPLAY HOLD ” key.
The message will be displayed until the “ DISPLAY
HOLD ” key is again pressed and released, or 10 min-
utes have elapsed, whichever comes first.
To Display CHILLED LIQUID TEMP Setpoint:
Use “ CHILLED LIQUID TEMP ” setpoint key as described
on page 23 to produce the following message:
LEAVING SETPOINT = XX.X°F
NOTE: The value displayed is the actual LCWT
setpoint. For example, the value displayed in
“ LOCAL ” or “ PROGRAM ” modes is that which
is operator programmed. The value displayed
in the “ REMOTE ” mode is that base setpoint
with added temperature reset by an Energy
Management System, via remote LCWT
setpoint (PWM signal) if a remote reset sig-
nal were received within 30 minutes.
To Display % ENGINE LOAD LIMIT Setpoint:
Use “ % ENGINE LOAD LIMIT ” setpoint key as described
above to produce the following message:
ENGINE LOAD LIMIT = XXX%
NOTE: The value displayed is the actual % engine
load limit setpoint. For example, the value
displayed in “ LOCAL ” or “ PROGRAM ” mode
is that which is operator programmed. The
value displayed in the “ REMOTE ” mode is
that which has been programmed by the En-
ergy Management System via the remote
engine limit setpoint input.