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Oil EXV Option —
If the chiller system is equipped with
an Oil EXV control valve, and the Oil EXV valve option in
CONF_OPT table (Option Configuration in the Configuration
Menu) is enabled, the PIC 5 control system will control the
opening of the Oil EXV valve to maintain the oil supply tem-
perature. The output of this valve is 4 to 20 mA. Before using
this function, configure the Oil Temp High Threshold and Oil
Temp Low Threshold options.
One minute after the compressor starts, if the oil supply
temperature is higher than the Oil Temp High Threshold, the
oil EXV valve should be in the fully opened position. If the oil
supply temperature is lower than the Oil Temp Low Threshold,
the oil EXV valve should be in the fully closed position. In all
other cases, the oil EXV valve position will be calculated ac-
cording to the oil supply temperature.
One minute after compressor shutdown is completed, the oil
EXV valve should be in fully closed position.
Pumpdown/Lockout —
The Pumpdown/Lockout fea-
ture prevents compressor start-up when there is no refrigerant
in the chiller. To access this function one must be logged in as
Advanced User/Service or higher. The feature can accessed
from the Maintenance Menu. See Fig. 54.
The Pumpdown/Lockout function provides precautions
when an external pumpout unit is removing refrigerant from
chiller. When the lockout is activated, the controller takes
the following steps:
• Starts water pumps and confirm flows
• Monitors evaporator pressure, condenser pressure, and evap-
orator refrigerant temperature during pumpout procedures
• Turns pumps off after pumpdown
• Proceeds to lock out the compressor
The Terminate Lockout feature ends the Pumpdown/
Lockout after refrigerant is added. Press End Lockout on the
Pumpdown/Lockout menu in order to initiate the process,
which proceeds as follows:
• Starts pumps and confirm flows
• Monitors evaporator pressure, condenser pressure, evap-
orator temperature during charging process
• Terminates compressor lockout
Displaying Data Trends —
The PIC 5 control system
offers the ability to configure and display color-coded system
trends without a password. Select Main Menu
Trending.
On the Trending screen (see Fig. 55), check the data to be
tracked, and set the beginning and end points for the selected
data. To change a data color, select the colored square and
choose a new color from the pop-up color bar. To view data
trends, select the down arrow at the bottom right of the Trend-
ings screen. The next page displays the selected data in the cho-
Fig. 51 — Master/Slave Config Screen, Page 1
Fig. 52 — Master/Slave Config Screen, Page 2
Fig. 53 — Master/Slave Config Screen, Page 3
Pumpdown/Lockout
a19-2335
Chilled Water Pump
Chilled Water Flow
Evaporator Pressure
Condenser Water Pump
Condenser Water Flow
Condenser Pressure
Evaporator Refrig Temp
Compressor Run Status
Fig. 54 — Pumpdown/Lockout Screen
Trending
a19-2336
Fig. 55 — Trending Screen Set-Up Page