24
CONTROL TEST — This feature allows the operator to
quick-test the controls and related hardware, including all unit-
controlled outputs except compressor output.
The unit must be off to run the test function. If the unit is on,
the test function cannot be accessed. The compressor can only
be started after the control test is finished. The test function
also requires the user to enter the User password if it has not al-
ready been entered. All control test parameters are accessible
through the Quick Test table. To perform the control test func-
tion, set the first item Quick Test Enable in the Quick Test table
to Enable.
Unless otherwise noted, all protective limits remain active
during the controls test.
Discrete Outputs — When the control test is enabled, discrete
outputs can be enabled using the Quick Test table. Discrete
valves that can be tested in Quick test are: GV1 Open, GV1
Close, Oil Pump Relay, HGBP Open, HGBP Close, Damper
Open, Damper Close, Condenser Pump Relay, Evaporator
Pump Relay, Alarm Relay, and Alert Relay.
NOTE: The following outputs cannot be enabled at the same
time Guide Vane Increase and Guide Vane Decrease are
enabled: EC/HGBP Valve Open and EC/HGBP Valve Close;
Economizer Damper Valve Open and Economizer Damper
Valve Close.
NOTE: For oil pressure, a value
18 psi within 40 seconds
after the oil pump is turned on indicates a confirmation of pres-
sure (Oil Pres Test Passed=YES).
Analog Output — When the control test is enabled, the fol-
lowing analog outputs can be enabled by entering the positions
in the QCK_TST table:
• Head Pressure Valve
• Diffuser Actuator
• Oil EXV (electronic expansion valve)
• Chiller Status Output (Q_CHST)
Guide Vane Calibration — The guide vane position should be
calibrated before starting the chiller. Guide vane calibration can
be started by setting Quick Test Enable to Enable and GV1
Calibration Enable to Enable.
If the actuator type is digital (POS) 0, then:
• The fully closed guide vane feedback resistance will be
in the range of 62.5 ohms to 688 ohms (350 ± 75 ohms
target setting).
• The fully opened guide vane feedback resistance will be
in the range of 6190 ohms to 11,496 ohms (10,000 ohms
target setting).
If the actuator type is analog (1):
• The fully closed guide vane feedback mA value will be
in the range of 3 mA to 5 mA.
• The fully opened guide vane feedback mA value will be
in the range of 19 mA to 20.8 mA.
SWIFT RESTART (CAPACITY RECOVERY™) — This
function is designed for data center or other applications. It
allows the chiller to be restarted quickly to meet building
load requirements.
To enable this function, the AUTO RESTART OPTION
point in the CONF_OPT table should be set to ENABLE.
The water flow verification time, oil prelube time and other
delays will be decreased compared to a normal start-up.
COOLING TOWER CONTROL — If WATER PRESSURE
OPTION in the CONF_OPT table is set to 1 or 2, there will
be another optional hydraulic control I/O board in the PIC 5
control system to allow PIC 5 control for the water pumps
and cooling tower fans (high speed and low speed).
The cooling tower fans are controlled by the pressure differ-
ence between condenser and evaporator and entering water
temperature of condenser. The objective is to maintain the en-
tering condenser water temperature in the optimal range.
HEAD PRESSURE CONTROL — If the chiller system is
equipped with a head pressure control valve, and the HEAD
PRESSURE VALVE option in the CONF_OPT table is EN-
ABLED, the PIC 5 control system will control the opening of
the head pressure valve to maintain the pressure difference be-
tween condenser and evaporator. The output of this valve is 4
to 20 mA type.
Before using this function, the pressure difference values for
20 mA and 4 mA should be set.
The head pressure valve should be in fully closed position
when chiller is in OFF mode.
ICE BUILD OPTION — The PIC 5 controller provides an
ice build option based on efficiency improving point. The ICE
BUILD OPTION in the CONF_OPT table should be set to
ENABLED to make ice build active, and the following two pa-
rameters should be configured:
• Ice_recy (ICE BUILD RECYCLE) indicates whether
recycle option is enabled in ice build mode.
• Ice_term (ICE BUILD TERMIN SOURCE) indicates
how the ice build is terminated. There are three types:
temperature (0), dry contact (1), or combined tempera-
ture and dry contact (2).
TIME SCHEDULE — The PIC 5 control provides three
schedules:
• Local schedule
• Ice build schedule
• Network schedule
Each schedule has 8 time segments. If two time segments
overlap, the unoccupied time segment takes priority.
There are 16 holiday time segments. Each holiday time seg-
ment is determined by three parameters—month, start date,
and holiday days. The controller will be in unoccupied mode
when a holiday time segment is active. PIC 5 includes a Day-
light Savings Time function. Use Broadcast Menu to enable
this feature and configure start and end dates.
BLACK BOX — The black box task continuously stores
parameters in memory every 5 seconds. Reporting of a chiller
operation alarm triggers the controller to generate a collection
of data records. Each collection contains up to 180 records that
consist of 168 records (corresponding to 14 min.) before the
alarm and 12 records (corresponding to 1 min.) after the alarm.
Each record is associated with a time stamp. Files are saved as
csv files; up to 20 files can be stored.
The black box file can be uploaded with the Carrier S-Ser-
vice tool. Once the upload is done, the original files are auto-
matically deleted.
PRESSURE TRANSDUCER CALIBRATION — The HMI
pressure readings are displayed in the Main Menu
Pressures
screen. See Fig. 32 and 33.
