York YCUL0045E, Установка, эксплуатация и обслуживание

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JOHNSON CONTROLS
59
FORM 150.63-NM8 (1020)
2
These messages indicate that the zone thermostats
for system 1 and system 2 are open. These messages
will only be displayed when the Control Mode is pro-
grammed for Suction Pressure.
The anti-coincidence timer is a software feature that
guards against 2 systems starting simultaneously. This
assures instantaneous starting current does not become
excessively high due to simultaneous starts. The micro
limits the time between compressor starts to 1 minute
regardless of demand or the anti-recycle timer being
timed out. The anti-coincidence timer is only present
on two system units.
When this message appears, discharge pressure limiting
is in effect. The Discharge Pressure Limiting feature is
integral to the standard software control; however the
discharge transducer is optional on some models. There-
fore, it is important to keep in mind that this control will
not function unless the discharge transducer is installed
in the system.
The limiting pressure is a factory set limit to keep the
system from faulting on the high discharge pressure
cutout due to high load or pull down conditions. When
the unload point is reached, the micro will automati-
cally unload the affected system by de-energizing one
compressor. The discharge pressure unload will occur
when the discharge pressure gets within 15 PSIG of the
programmed discharge pressure cutout. This will only
happen if the system is fully loaded and will shut only
one compressor off. If the system is not fully loaded,
discharge limiting will not go into effect. Reloading the
affected system will occur when the discharge pressure
drops to 85% of the unload pressure and 10 minutes
have elapsed.
When this message appears, suction pressure limiting is
in effect. Suction Pressure Limiting is only available on
units that have the suction pressure transducer installed.
If a low pressure switch is installed instead, suction
pressure limiting will not function.
The suction pressure limit is a control point that limits
the loading of a system when the suction pressure drops
to within 15% above the suction pressure cutout. On a
standard system programmed for 44 PSIG/3.0 Bar suc-
tion pressure cutout, the micro would inhibit loading of
the affected system with the suction pressure less than
or equal to 1.15 * 44 PSIG/3.0 Bar = 50 PSIG/3.5 Bar.
The system will be allowed to load after 60 seconds
and after the suction pressure rises above the suction
pressure limit point.
This message indicates that load limiting is in effect and
the percentage of the limiting in effect. This limiting
could be due to the load limit/pwm input, ISN or RCC
controller sending a load limit command.
If MANUAL OVERRIDE mode is selected, the STATUS
display will display this message. This will indicate that
the Daily Schedule is being ignored and the chiller will
start-up when chilled liquid temperature allows, Remote
Contacts, UNIT switch and SYSTEM switches permit-
ting. This is a priority message and cannot be overridden
by anti-recycle messages, fault messages, etc. when in
the STATUS display mode. Therefore, do not expect to
see any other STATUS messages when in the MANUAL
OVERRIDE mode.
MANUAL OVERRIDE is to only be used in emergencies
or for servicing. Manual override mode automatically
disables itself after 30 minutes.
S Y S 1 A C T I M E R X X S
S Y S 2 A C T I M E R X X S
S Y S 1 D S C H L I M I T I N G
S Y S 2 D S C H L I M I T I N G
S Y S 1 Z O N E T H E R M O F F
S Y S 2 Z O N E T H E R M O F F
S Y S 1 S U C T L I M I T I N G
S Y S 2 S U C T L I M I T I N G
S Y S 1 L O A D L I M I T X X %
S Y S 2 L O A D L I M I T X X %
M A N U A L
O V E R R I D E