System information

30
Oil Filter Alert
— This function is active only in an oil pump
control test. If the oil pump is forced to ON and after 10 sec-
onds, if the pressure differential between oil pump pressure
and oil discharge pressure is lower than the threshold set in the
Oil Filter Pres Diff field, the filter needs to be replaced and the
dedicated alert 160 is reported until the oil pressure differential
is higher than the alert threshold plus 2 psig. Then set the Oil
Filter Change Done option to YES manually.
Refrigerant Transducer Calibration
— When the unit is
offline for more than 5 minutes, a comparison is made of the
evaporator, condenser, and economizer refrigerant pressure
transducers. A difference of more than the configurable thresh-
old set in the Trans Calib Threshold option generates an alert
161 that a calibration is required. The comparison is done for
all of the transducers. After calibration, set the Trans Calibra-
tion Done option to YES manually.
Low Refrigerant Charge
— This function uses the evapora-
tor approach (Evap Design Approach) setting and compressor
discharge temperature (Bearing Degradation) setting in rela-
tion to the condenser refrigerant temperature (Low Charge
Cond Approach) setting to generate an alert 162 of possible
low refrigerant charge. After correcting the charge, set the
Refrigerant Charge Done option to YES manually.
MASTER SLAVE CONTROL — This control, available
from page 2 of the Configuration Menu, provides the capabil-
ity to operate 2 chillers in Master/Slave mode. The slave chiller
should be set to NETWORK mode and controlled by the mas-
ter chiller.
The two chillers can be configured to be in parallel or in se-
ries. When they are in series mode, master and slave chillers
can be configured to be upstream or downstream. The master
chiller monitors all external commands, such as start/stop, de-
mand limiting, or setpoint configuration.
The master/slave function provides the ability to select a
lead chiller from the master and the slave chillers. Selection is
based on the delta between the master and the slave run hours,
and tries to optimize the runtime hours. If this function is not
set, the lead chiller is always the master chiller and should be
changed to lag when it fails.
The lead chiller shall always be started first, and the lag
chiller shall be maintained at zero percent capacity. When the
lead chiller cannot be loaded anymore, then the lag start timer
is started. The lag chiller shall always be stopped first.
If a communication failure is detected between the master
and the slave chillers, all master/slave functions are disabled
and chillers return to stand-alone operations until communica-
tion is reestablished.
Displaying Data Trends — The PIC 5 control system
offers the ability to configure and display system trends wi-
wthout a password. Select Main Menu  Trendings.
On the Trendings screen (see Fig. 47), check the data to be
tracked. Set the beginning and end points for the selected data.
To change a 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 Trendings screen. The
next page displays the selected data in the chosen colors. See
Fig. 48.
DIAGNOSTICS AND TROUBLESHOOTING
The 19XR PIC 5 control system has many fault tracing aid
functions. The local interface and its various menus give access
to all unit operating conditions.
If an operating fault is detected, an alarm is activated. The
alarm code is displayed in the Alarms menu, sub-menus Reset
alarms and Current alarms. The control may record up to 10
current alarms.
Displaying Alarms — The alarm icon on the interface
(see the section Icons on page 17) indicates unit status as fol-
lows:
• A flashing LED shows that the unit is operating but there
is an alert.
• A steady LED shows that the unit has been shut down
due to a fault.
The Reset Alarms option on the main menu displays up to
five alarm codes that are active on the unit. Table 15 lists alarm
codes. The Current Alarms option displays details for each
alarm.
Resetting Alarms — When the cause of the alarm has
been identified and corrected, the alarm can be reset either au-
tomatically or manually (depending on the type of alarm).
Alarms can be reset without stopping the machine.
In the event of a power supply interrupt, if Auto Restart Op-
tion is set to ENABLE in the Option Configuration menu, the
unit restarts automatically without the need for an external
command. However, any faults active when the supply is inter-
rupted are saved and in certain cases may prevent a unit from
restarting.
Trendings
Fig. 47 — Data Logging and Trending Screen
Set-Up Page
Trendings
Fig. 48 — Data Logging and Trending Screen
Display Page