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Discrete Outputs
The Quick Test Menu allows testing of the following discrete out-
puts: Hot Gas Bypass, Oil Pump, Oil Heater - Primary, Oil Heater
- Secondary, Vaporizer Heater, Alert Relay, Alarm Relay, Running
Relay, Evap Pump, Condenser Pump.
Analog Output
The Quick Test Menu allows testing of the following analog out-
puts: Main EXV, Economizer EXV, Oil Reclaim Valve position,
Unit Status, and Head Pressure Output.
Once the controls testing is completed, disable the Quick Test
from the Chiller Start / Stop menu.
AUTO RESTART AND SWIFT RESTART
Controls have two restart options. Auto Restart can be selected
for automatic restart after power failure. When selected the unit
will automatically turn back on when power is returned to nor-
mal. Swift Restart is designed for data center or other applica-
tions. It allows the chiller to be restarted quickly to meet building
load requirements.
To enable this function, user must navigate to Configuration
MenuService Configuration. In the Service Configuration
Menu set Restart Options to 1=Auto Restart and 2=Swift Restart.
See Fig. 38 and 39.
For Swift Restart.the water flow verification time, refrigerant
prelube time and other delays will be decreased compared to a
normal start-up. It is recommended to set the unit for 1=Auto
Restart unless there are special circumstances that require faster
than normal startup after power failure.
WATER PUMP CONTROL
Note that the chiller must always maintain pump control or
warranty may be voided. Carrier pump control is required to
help safeguard the chiller from evaporator and condenser
freeze conditions. In addition condenser pump control is re-
quired for condenser pressure override.
HEAD PRESSURE CONTROL
If the chiller system is equipped with a head pressure control
valve, and the HEAD PRESSURE VALVE option in the Head
Pressure Config table is configured, the PIC6 control system
will control the opening of the head pressure valve to main-
tain the pressure difference between condenser and evapora-
tor. The output of this valve is 4 to 20 mA type and is based
on the configurable Delta P (Condenser Pressure-Evaporator
Pressure) reference curve. Delta P at 100%, Delta P at 0%,
and Head Pressure Minimum Output are configurable param-
eters for this algorithm. The output is designed for use with
non-grounded controllers with a maximum impedance of
500 ohms. Head pressure reference output will be active
whenever the condenser pump is operating. If a condenser
freeze condition is detected the head pressure valve will auto-
matically go to 100% (20 mA).
Before using this function, the pressure difference values for
20 mA and 4 mA should be set. See Fig. 45 and 46.
The head pressure valve should be in fully closed position when
chiller is in OFF mode.
Fig. 45 — Minimum Head Pressure Reference Output
Fig. 46 — Head Pressure Configuration Menu
TIME SCHEDULE
The PIC6 control has the following schedules:
• Local schedule
• Holiday 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 segment 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. For Network and Remote Contact Starts
there are no Time Schedule tables. These are enabled at the Con-
figure Startup Options menu found at the Chiller Start/Stop Menu.
BLACK BOX
The black box task continuously stores parameters in memory ev-
ery 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 (correspond-
ing 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.
Any Alarm (not Alert) will trigger a Black Box recording and data
will be overwritten once 20 files are reached.
The black box file can be uploaded with the Carrier Service Tool
or the USB Log Export feature (Main MenuSystem Config
MenuUSB Log Export). For Black Box data select Export
Technical Data = Yes and install USB stick in the PIC6 controller
and then select Export Data.. Once the upload is done, the original
files are automatically deleted. See Fig. 47.
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